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Genotypic and phenotypic variation in populations of Daphnia pulex Krepp, Susan Rose 1977

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GENOTYPIC AND PHENOTYPIC VARIATION IN POPULATIONS OF DAP HNIA PULEX  BY SUSAN ROSE KREPP B.Sc., The P e n n s y l v a n i a  State University,  1974  A THESIS SUBMITTED I N PARTIAL FULFILLMENT OF THE REQUIREMENTS  FOR THE DEGREE OF  MASTER OF SCIENCE in THE FACULTY OF GRADUATE STUDIES Department o f  We a c c e p t  Zoology  t h i s t h e s i s as conforming required  to the  standard  THE UNIVERSITY OF BRITISH COLUMBIA SEPTEMBER, 1977 COPYRIGHT SUSAN ROSE K R E P P , 1977  In p r e s e n t i n g t h i s  thesis  an advanced degree at the L i b r a r y I  further  for  in p a r t i a l  of  freely  available  this  representatives. thesis for  Department o f The  It  financial  for  gain s h a l l  U n i v e r s i t y o f B r i t i s h Columbia  e  September 29. 1977  for  that  r e f e r e n c e and study. this  thesis or  i s understood that copying or p u b l i c a t i o n  Zoology  2075 Wesbrook P l a c e Vancouver, Canada V6T 1WS  t  requirements  t h a t p e r m i s s i o n f o r e x t e n s i v e copying o f  written permission.  a  the  s c h o l a r l y purposes may be granted by the Head of my Department  by h i s  D  of  the U n i v e r s i t y of B r i t i s h Columbia, I agree  s h a l l make it  agree  fulfilment  not  be allowed without my  i  Abstract  Because organisms  of  may  their  have  reproductive  limited  alternative  mechanisms  maintaining  phenotypic  parthenogenetic  g e n e t i c v a r i a t i o n and may r e l y on  other  than  genetic  variability  environment. T h i s hypothesis and phenotypic  pattern,  diversity  and  was t e s t e d by  adapting  measuring  for  t o the genotypic  v a r i a t i o n i n s e v e r a l p o p u l a t i o n s o f Daphnja jaulex  , an a p o m i c t i c , parthenogenetic Genotypic  cladoceran.  v a r i a t i o n measured by s t a r c h g e l e l e c t r o p h o r e s i s  i n d i c a t e d 0% v a r i a b l e l o c i  i n 3 s p e c i e s o f Da£hnia i n the  lower  mainland around Vancouver, B.C. and 3855 polymorphic l o c i i n Near Roundup, Lake.  a  pond  i n t h e I n t e r i o r of the province near  Differences  electrophoretic phenotypic  in  patterns  provide  variation i n 3  geographically  similar  electrophoretically  environmental a  conditions  rationale  electrophoretically,  ponds,  polymorphic  P2,  P4,  Williams  and  population  and  f o r comparing physically  P5, (NR)  and  and  i n an  which  are  p h y s i c a l l y and g e o g r a p h i c a l l y d i s t i n c t . Means  and  variances  of  5  morphological  and  1  to  6  r e p r o d u c t i v e c h a r a c t e r s were compared w i t h i n and among c l o n e s i n each  population  following:  1)  and There  among  populations  were s i g n i f i c a n t  and  indicated  the  d i f f e r e n c e s i n means f o r  most c h a r a c t e r s among c l o n e s and among p o p u l a t i o n s r e g a r d l e s s o f electrophoretic similarity populations,  2)  There  was  or  dissimilarity  among  clones  greater i n t r a c l o n a l v a r i a t i o n  or than  interclonal variation there  was  i n a l l populations  significantly  v a r i a n c e , and  greater  for a l l characters,  total  variance,  i n t e r c l o n a l v a r i a n c e i n P2  than  v a r i a n c e s were p a r t i t i o n e d e q u a l l y w i t h i n and w h e r e a s t h e g r e a t e s t % v a r i a t i o n i n NB These phenetic  data  suggest  variability  t h a t P2 and  NR  an  populational  inverse  i n these  are examples  of  homeostasis.  also rely  i n order on  by  the r e l a t i v e l y variation  the  among c l o n e s i n  relation  of g e n e t i c  by  rely  plasticity  on  to  which  extreme  possible  a  population.  These  interpreted  r e l a t i v e to s e l e c t i o n  the  and are  may  extent  as  however,  electrophoretic  g e n e t i c changes i n the  strategies and  and  Daphnia  within clones,  by  P2  phenotypic  lesser  v a r i a n c e and  adaptation  4)  suggest  individual  individuals  large % variation  indicate  and  within clones.  adaptation P2  small absolute  may  HR,  t o a d a p t t o t h e e n v i r o n m e n t . NS  phenotypic  demonstrated  intraclonal  p o p u l a t i o n s o f D a p h n i a and  e l e c t r o p h o r e t i c a l l y monomorphic may plasticity  was  in  3)  have  temporal  been  further  stability  of  the  environment. Phenotypic i n D a p h n i a and suggest t h a t changes  and  l a c k of e l e c t r o p h o r e t i c v a r i a t i o n  i n other parthenogenetic these  evidence  to  suggests  variation in  variation that  c o n s t r a i n e d by t h e  dependent  parthenogenetic  i n sexually reproducing  genetic  mode o f  not  organisms  i n t h e p o p u l a t i o n t o s u r v i v e . T h e r e i s however phenetic  are  inbreeding  genetic  comparable  organisms  and  on  o f g e n e t i c and  this  plasticity  variation  reproduction.  is  not  organisms  organisms  and  necessarily  i i i  Table  Of  Contents  V  L I S T OF FIGURES LIST  OF T A B L E S  ............................................  ACKNOWLEDGEMENTS  .. . .  v i i i  ..................  1  .....................................  10  INTRODUCTION MATERIALS RESULTS  AND  AND  METHODS  DISCUSSION  Electrophoresis  19  ........................................  Comparison  O f P 2 , P4, And P 5 ; F i e l d  Comparison  O f P 2 , P4, And P5: L a b And F i e l d  Comparison  O f P2, P4, And P5: L a b Data  Comparisons  O f P 2 , P4, And  Variation  P5:  Data  Inter  O f P 2 , P 4 , A n d P 5 ; Summary  Comparison  O f P2 A n d NR  .......  34  .................  43  And  Data  Intraclonal 44  ..................  53  ................................  55  Comparisons  O f P 2 A n d NS: I n t r a p o p u l a t i o n  Results  F o r P2  Comparisons  O f P2 A n d NR:  Results  F o r NR  Intrapopulation  Interpopulation  Comparisons  O f P2  And NR: M e a n s  Interpopulation  Comparisons  O f P2  And NR: V a r i a n c e s  Comparison  O f P2 A n d NR:  Comparison  O f P2 A n d NR: T e m p e r a t u r e  ........ ....  Summary  62 63 69  Experiment ........  DISCUSSION  Environmental  19 25  ...........................................  Comparison  FINAL  v i i  72 81  Stability  O f P2 A n d NR  ................... .  87  LITERATURE  CIT  Figure  1 : Location  Vancouver,  Of  LIST  OF  Ponds  In  And I n C e n t r a l  FIGURES  The  B.C.  Lower  Near  Figure  2 : Morphological  Figure  3 : E l e c t r o p h o r e t i c Polymorphism  X* A P Xi oo x* Figure  4 :  Distribution  7  Distribution  Field  P4,  And  Figure In Figure  9 :  In Figure In  11 P2  ES, And  •••••21  And  Body L e n g t h s pulex Of  From  Body  And L a b  . . . . . . . . . . . . . . . . . . 28 In  Field  And  Lab  ..................30  Length In F i e l d  And L a b  ...................32  Of  F o r Body  Daghnia  And 9 5 % C o n f i d e n c e L i m i t s Lab P o p u l a t i o n s And  And  Length  p u l e x From  For  O f P 2 , P4, And  95% C o n f i d e n c e L i m i t s Of P2,  95% c o n f i d e n c e  Daphnia  : Means And NR  P5.  ...  Component V a r i a b l e s  And NR  P2.  In F i e l d  P2,  v  Means  And  11  .............. .............................38  10 : M e a n s P2  A t T h e AKP,  And 9 5 % C o n f i d e n c e L i m i t s  8 : Means Field  P5.  From  And L a b P o p u l a t i o n s  P5.  Principal Figure  From  : Means  In  Lake.  P h e n o t y p i c V a r i a t i o n . 16  Body L e n g t h s  pulex  Of  Of Daphnia  Populations Figure  Of  Of D a p h n i a  5 : Distribution  6 :  Near  •*•«••»  Populations Figure  Of  Williams  .x  Populations Figure  Measures  mainland  Reared  P4,  Limits  At T h r e e  Reared  At Three  Number  P 5 . . . . . . . . . . 40 For The  And P5.  Three  .......47  F o r Body  Temperatures.  95% C o n f i d e n c e L i m i t s  Daphnia  Egg  F o r Egg  Temperatures.  Length .....77 Number .....79  vi  LIST  Table  1.  Electrophoretic  Inbreeding Table The Table  2. Summary Lakes 3.  4.  In This  Table  Per Cent  The  5.  Daphnia Table  6.  And' Table In Table  Estimates  P2, Table And Table P4,  Data  And C h e m i c a l  Data  8. C o m p a r i s o n  For  F o r The 14  Loci  In  22  Populations  , And D a p h n i a  laevis  For A l l e l e s  Measured  Frequencies  For Three  Of  .....20 From  The  Mean,  F o r P 2 , P 4 , A n d P5 Of L a b And F i e l d  Variance, Field  Variances  And  10. C o m p a r i s o n  95%  Populations In  P2,  .26  P4,  .......35 Of L a b A n d F i e l d  Variances  {%  Variation ,...36  Estimates Limits  Of  .....24  P 2 , P4, And P5 9.  Of  Species  ......... .  Confidence Table  Environmental  4  Roundup Ponds  Allele  7. C o m p a r i s o n P5  In The L i t e r a t u r e  13  Designations  Limits  And  Study  , DaBknia. £ o s e a  And  In P a r t h e n o g e n e t i c  ............. .  Confidence Table  Reported  aonomorphic  Numerical  Origin,  Variation  Of The P h y s i c a l  And N e a r  Da.2hn.ia j o u l e x  TABLES  O f The A v a i l a b l e  Summary  Peterson Table  Organisms  OF  Of  The  Mean,  F o r P2, P4, And Of W i t h i n  Variance,  And  95%  P5 L a b P o p u l a t i o n s « . . 4 2  And Among  Clone  Variation  In  P 4 , A n d P5 11. C o m p a r i s o n Among 12.  Of V a r i a t i o n  Populations  Summary  And P5  50  Of  Within  P2, P4, And The R e s u l t s  And  Among  Clones  P5 From  ,...52 Comparisons  Of  P2, .54  vii  Table  13. E s t i m a t e s Of Means, V a r i a n c e s , And 951  Confidence  L i m i t s F o r P2 And NS Table  .58  14. C o m p a r i s o n O f W i t h i n And Among C l o n e  Variation In  P2 And NE Table  59  15. R a t i o Of V a r i a n c e s W i t h i n And Among C l o n e s I n  And  NR  From  Transformed  Untransformed  And  Logarithmically  D a t a .......,..................... ..........60  Table  16. C o m p a r i s o n O f V a r i a n c e s F o r NR And P2  Table  17.  F  Tests  Transformed  Comparing  Data  P o p u l a t i o n s P2 And NS Table And Table  P2  Within  Relative And  ...........64  Variances  Among  Clones  From Between  ..................................66  18. C o m p a r i s o n O f V a r i a t i o n W i t h i n And  Among  Clones  Between P o p u l a t i o n s P2 And NR  63  19. Summary Of The G e n e t i c D a t a From P2 And NS  T a b l e 20.  Means  Reproductive  And  Variances  Characters  P2  And  For NR  ......70  Morphological Reared  At  And Three  T e m p e r a t u r e s ...........................................73 T a b l e 2 1 . C o m p a r i s o n O f Means And V a r i a n c e s I n P2 And NR  At  T h r e e T e m p e r a t u r e s ................. . . . . . . . . , . . . . , 7 6 T a b l e 2 2 . C o m p a r i s o n s Of M o r p h o l o g i c a l C h a r a c t e r s I n P2 And NR . . ,. T a b l e 23.  ,. . Means  And V a r i a n c e s  85  F o r F i t n e s s B a s e d On  Of S u r v i v o r s And Number Of E g g s I n P2 And NR  Number  ...........90  v i i i  ACKNOWLEDGEMENTS  Without Dr.  William  has  been  indebted graduate  I and  completely  The  this  support, study  unselfish  would  with  t o him f o r h i s genuine student  also  the twins i n my  advice,  E. N e i l l  in  me  who h a v e  interest  and c r i t i c a l  evaluation of  n o t have been  h i stime interest  possible.  and energy  and I  i n my d e v e l o p m e n t  He am as a  and r e s e a r c h e r .  indebted  confidence  and me  am  the  t o Mark  Denny  throughout  f o r h i s unending  this  study,  patience  a n d t o my  unguestioningly supported  and  parents  encouraged  i n biology.  motivation Adrienne  and  friendship  Judy  Neill,  Peacock,  John  been  i n v a l u a b l e t o me t h r o u g h o u t  of Bill  Spence,  this  Clark,  and C a r l  study.  Judy  Myers,  Whitney  have  1  IHTBODUCTION  "The material is  basis  of individuality  of science  the material  a n d v a r i a t i o n among  of genetics"  Classically  (Clarke,  phenotypic  and p h y s i o l o g i c a l  populations.  Phenotypic  of species  characters, moths,  such  have  been  as  has  color  demonstrated  been  h a s been  few s p e c i e s  shell  i s  of a  the  species  197 4) .  variability  variation  and f o r a  t h e members  variation  morphological  number  i s variation. Variation  measured  as  within  and  among  studied  i n a  large  of  some  polymorphisms  i n s n a i l s a n d wing  t o be s e l e c t i v e l y  color i n  important  (Ford,  1976) .  Genetic  variation  qualitative genetic  and  basis  populations measured the  of  polymorphisms  of  this  of explanations perception  fine-grained  associated  organism,  strategies; flow.  of  with  (Selander  rate This  the  of mutation study  selection  deals  Kaufman,  among  of  protein  (Selander,  and  i n both 1976).  interpreted  by a  1968);  as being  coarse-  the or  and the homeostasis o f 1973);  and Kimura,  with  variability  (Levins,  environment  (Crow  whose  has been  the mobility  and  characters  v a r i a t i o n h a s been  i s considerable  on  of  by e l e c t r o p h o r e s i s  variation  variation  based  genetic  detected  measurements  in  chromosomal  recently  and i n v e r t e b r a t e s  by  variation  by  Hore  determined  electrophoretic  maintenance  organisms  gene  i s known, a n d  b y enzyme  degree  number  the  quantitative  or species.  vertebrates The  has been  reproductive  1965) a n d r a t e o f  genotypic  and  phenotypic  2  variation  associated  parthenogenesis. of  with  Phenotypic  morphological  and  i s  inter-  intraclonal  One asexually  due  to  1)  2)  hypothesis  have  been  another  reproduced the  and  study, in  however,  Daphnia  apomictic (Wright also  been  shown  bees  which  a  European  and  are  Kaufman,  tesselatus Selander,  spp  as  be  and  land 1973  which 1976)..  snail ),  and  has  eliminating  which in  the  variation  been  a  i s a  been  most  of  in  an  in three  selfer  large for  Other  lizards have  lack species  Sumina  lizard,  from  196 9)  total  in  in  variation  1971),  A  facultative  reported  has  earlier  {1927).  (Suomalainen,  hand,  for  sexually  phenotypic  (Solbrig,  1974),  and  individuals  asexually  observed  this  l o n g i s p i n a and  of of  decollat (Selander  Cnemidophorus  parthenogenetically  other have  of  triploid  in  variation  Wood  variable.  (Snyder,  reproduces On  and  weevils  extremely  variation  and  amounts  or  reproducing  morphological  Daphnia  dandelions  1967)  to  of  recombination  comparisons  Banta  sexually  haplo-diploid  electrophoretic  and  phenotypic  in  similar  such  Lowe,  comparisons  contradicting  f o r both  Reduced  1939).  reported  electrophoretic  a  Hoina  reproduced  and  and  parthenogenetic  (Banta,  organisms  measures genotypic  in sexually  p a r t h e n o g e n e t i c a l l y reproduced  same c l o n e s  and  by  selection  supporting  in  cladoceran,  by  parthenogens  assortment  directional  reported  in  than  random  variability.  demonstrated  variability  variation  organisms  and both  strategy,  is classified  e l e c t r o p h o r e s i s and  lack of  Data  electrophoretic  variation  less  genotypes.,  reproductive  variation.  expect  chromosomes,  been  by  reproducing  organisms of  measured  might  unique  physiological  variation and  a  (Parker  and  amounts  of  parthenogenetic  3  populations  of  lizards  (Suomalainen  and  Saura,  unpublished  data;  self-pollinating from  the  1.  1973),  and wild  Proposed  parthenogens stabilizing  and  and  oats on  ailard,  organisms for  are  and  and  in  1970).  Data in  summarized  of  variation  incorporation  heterosis,  Young,  variation  maintenance  increased  selection,  and  weevils  1974;  1976),  electrophoretic  explanations  1976),  (Hebert,  Fraser,  (Marshall  reproducing  include  Selander,  cladocerans  Smith  literature  parthenogenetically Table  (Parker  of  large  in in  mutations, amounts  of  immigration.  Daphnia the  year.  based  to  cytological (Hebert  recombination  1965),  not  occuring  Daphnia sexual  temperature, 1969).  Daphnia  1936)  1974),  siblings  are  similarity  these  also  stimuli or  Females  can  and,  in  since  food,  I  large  any  no have  be  of  ameiotic  variation  al.  (1961  rise  to  due and  i s endoraeiotic  give  this  to  parts  electrophoretic  et  parthenogenesis  electrophoretically, in  Bacci,  recombination  of  and  eliminating  offspring. that  during  i s thought  single parthenogenetic  reproduction  demographic  Hard,  the  similarity  sibs  in  (Mortimer,  argue  within  electrophoretic among  in  assume t h a t  variability genetic  and  however,  therefore  parthenogenetically  Parthenogenesis  on'  studies  reproduce  and  genetic  lines  of  D a p h n i a -..  The  study  i s recognized  by  v a r i a t i o n was assumed  observed  endomeiosis  i s  organisms.  capable in  of  producing  response  associated and  usually  increasing produce  to with  males  subsequent  environmental  and/or  decreasing  population two  and  density  ephippial  light, (Stross,  eggs  which  Table 1  : E l e c t r o p h o r e t i c v a r i a t i o n i n p a r t h e n o g e n e t i c and i n b r e e d i n g organisms i n the l i t e r a t u r e .  reported  organism  mode o f reproduction  variable loci total loci  reference  Rumina d e c o l l a t a  facultative self-fertilization  0/25  (0%)  S e l a n d e r and Kaufman (1973)  Augochiora pura L a s i o g l o s s u m zephyrum Bombus americanorum  haplo-diploidy  0/13 0/24 0/12  (0%) (0%)  Snyder  D r o s o p h i l a mercatorum  parthenogenesis  5/10 7/12  (50%) males (58%) females  Templeton, C a r s o n , and S i n g (1976)  O t i o r r h y n c h u s s c a b e r (3N) 0. s c a b e r (4N) 0. s i n g u l a r i s (3N) Strophosomus melanogrammus  parthenogenesis  16/26 16/26 16/23 9/20  (62%) (62%) (70%) (45%)  Suomalainen and (1973)  parthenogenesis  6/21 0/21  (29%) (0%)  P a r k e r and S e l a n d e r (1976)  4/23  (17%)  V r i j e n h o e k and L e s l i e (197 )  5/16 7/13  (31%) (54%)  M a r s h a l l and A l l a r d (1970)  Cnemidophorus t e s s e l a t u s C. t e s s e l a t u s (3N)  (3N)  (2N)  P o e c i l i o p s i s 2 monacha-lucida  Avena b a r b a t a Avena f a t u a  gynogenesis  autogamous s e l f fertilization  (1974)  (0%)  Saura  Table 1 : Electrophoretic v a r i a t i o n i n parthenogenetic and inbreeding organisms reported i n the l i t e r a t u r e (cont.). organism  Simocephalus  Daphnia magna D. pulex  serrulatus  mode of reproduction  variable l o c i total loci  parthenogenesis  5/16 to 9/16 (31% to 56%)  Smith and Fraser (1976)  parthenogenesis  4/13 3/8  Hebert (1974) Young (unpub1. data)  (31%) (37%)  reference (%)  6  overwinter stimulus.  i n the This  individuals  not  of  dispersal  genetic  material  phenotypic  and  by  for  1957).  accurate  difficult.  cyclomorphic,  in  Cyclomorphosis spine  to  with  food  1946;  review  high  and  of  a l l  but  rapid  are  Because  importance  bases:  also  r e o r g a n i z a t i o n of  interesting of  be  they  are  organisms genotypic  Harris  head  for and  of  and  by  and  described  1940)  and  in  of  be  Zaret,  Daphnia  species  may  also  adaptation Dodson,  the  and  in has be  change females.  diameter  temperature of  Horth  morphology  i n eye  1972;  turbulence  among  in  parthenogenetic  an  of  regional differences  carapace  increasing  and  to  length predator  1974)  and  i s  correlated  environment  (Brooks,  1967).  measures  comparable and  amounts  c h a r a c t e r i z a t i o n s of  to  Hutchinson,  (1966)  these  p r e v i o u s l y been  Large  been  (Carl,  i n changes  1966;  have .,  have  variation  thought  supply  are  Daphnia  generations  induced  by  of  Because  resulting i s  variation  taxonomic  Electrophoretic  species.  the  Columbia  that  (Jacobs,  cladocerans  f e c u n d i t y and  are  Daphnia  Phenotypic  successive  avoidance  in  British  (Brooks,  phenotype,  presumed  of  reproduction.  Daphnia  populations  in  tail  covers  eggs,  genotypic  populations  of  the  environmental  ideally  parthenogenesis,  sexual  and  variation  through  appropriate  variation.  phenotypic  been  of  evaluation of  Phenotypic described  after  capable  with  parthenogens,  measurement  hatch  only  associated  capable  America  and  reproductive strategy  are  colonization  acyclical  lake  to  of  genetic  those  Lewontin  and  of  variation  sexually  Hubby  (1966)  in  reproducing in  studies  7  of  humans and D r o s o p h i l a c o n c u r r e d i n f i n d i n g  variable l o c i  (comparable  Paphnia p u l e x  which  Simocephalus a l s o variable  loci  are  was  variation  variable  highly  i n several  Phenotypic  to  at  is  Daphnia  with  presumably  organism  this  phenotype, (1965)  and e n v i r o n m e n t  proposed  phenotypic  an  Further, and  population.  is  the  one would  be  expect  associated  homeostasis  (Thoday,  of  i n which e a c h  expression  of the  Phenotypic  plasticity,  characteristic environments assume in  different to  duration  terms  the  which  the  genotype,  in  in  of  of  phenotypes. changes  two  alternative  and  populational  than  the  the  fitness  of  is  to  the  changed  environment  generation  the  1965).  individual  i s capable o f modifying the environment.  by  time  of the  different  genotype  This i s p a r t i c u l a r l y  in  ina  phenotypic  1957, and L e v i n s ,  response  genotype  the  and  t h e amount by w h i c h t h e e x p r e s s i o n a  which  mean p h e n o t y p e  o f e n v i r o n m e n t s by  P o p u l a t i o n s may a l s o a d a p t t o a v a r i e t y the d i f f e r e n t i a l  1976).  interaction  (Bradshaw, 1965) , c a n p e r m i t a s i n g l e  acclimating  shorter  of  some  Lewontin,  individual  genotype  variances  individual  P o p u l a t i o n s may a d a p t t o a v a r i e t y flexibility  of  genotypic  in  with 1953;  %  be p r o p o s e d . , F a l c o n e r  i n describing  discussed  strategies  in  60  sum o f g e n e t i c and e n v i r o n m e n t a l  interaction  can  will  model  t h e environment  This  variation  i n Daphnia  and  by  s t u d y a model r e l a t i n g  additive  variation  variation. genotype  in  to  influenced  and by t h e e n v i r o n m e n t  and  33  (Smith and F r a s e r ,  genotype o f t h e i n d i v i d u a l lives,  magna  31 t o 38% o f a l l l o c i ) .  polymorphic  populations  variation  in  a p p r o x i m a t e l y 30%  to  advantageous  which  are of  o f t h e organism.  o f e n v i r o n m e n t s by u s i n g  individuals  where  multiple  8  genotypes  are each  plasticity to  in  assume  a  these  single  Levins  and  wild  oat,  have  environment.  enable  Phenotypic  different  genotypes  mathematical  inverse  wild  as  relationship  i n the  oat, by  and  of  ft.  t h e s e two by  of  structure  fatua,  the  strategies  Levins,  phenotypically  these  genotypic to  population  and  predicted  variable  model  A.  of  common  (Jain  and  barbata  is  more v a r i a b l e  than  fatua.  To  describe  evaluate  the  organism,  the  by  of  discussed  the in  field,  ponds, 30'  rationale  W,  this  at  122  of  and  and  variation P2 52  i n the 00»  f o r comparisons  49  i s also  lower N  i n of  to  of  P2,  the  will  and  and  of  model and  proposed  and  homeostasis. variances  of  are  compared  in  from  (designated  mainland,  P4,  be  of  and  populations  compared  a  to the  phenotype,  means  central  of  stability  variation  parameters)  01»N  needs  phenotypic variation  populational by  lab  one  fitness  genotype,  (determined  W,  and  populations  individual  39«  i e . the  analysis  £ulex  lab,  i n Daphnia  relative  physiological  Phenotypic  122  to  and  ponds  two  In  Daphnia  and  field  mainland  characters  variation  morphological  genotypic  relationship  relative  Phenotypic  adaptation,  measuring important  environment  from  adaptive strategies  environment. ,  describing  P5).  the  degree  ecologically  at  can  a  explained  and  less  specific  Differences  slender  been  1967);  genetically A.  provides  variation.  barbata. the  a  populations  s u g g e s t s an  Avena  Marshall,  to  phenotype.  (1965)  strategies phenotypic  adapted  P2,  for lab Near  three P4,  lower and  populations  Roundup  (NR)  British  Columbia.  The  P5  based  the  are  on  9  electrophoretic  similarity  and  similarity  geographic  comparisons  of  P2  and  dissimilarity  of  environmental  differences  hierarchically  1)  Regions, clones clone.  2)  i n each  these  between  among  NR  o f the populations of  population  based  populations among  a n d 4)  among  P4,  existence  Variation  P5,  f o r  electrophoretic  the  mainland  P2,  Rationale  on t h e  and  ponds.,  t h e lower  populations  pondSi  the  are  and t h e p h y s i c a l ,  and  i s compared  central  a n d N.R.,  individuals  of  B.C.  3)  among  within  each  10  RATERIALS AND  Da.2hnia Columbia  were  about  sampled  METHODS  i n 22 ponds, two i n c e n t r a l  35 km west of W i l l i a m s Lake near E i s k e Creek  20 i n the lower mainland near Vancouver M£hnia  fiulex  sampled  ,  DaEfeaiS r o s e a  ,  locations  and  ( F i g . 1 ) . Three s p e c i e s ,  and  Daphnia  i n 12, 5, and 5 ponds r e s p e c t i v e l y .  various  British  laevis  Several  ,  were  tows  from  i n the pond were taken using a Wisconsin net  30 cm i n mouth diameter with 220 n i t e x mesh towed from the shore or  from a boat.  physical  and  There  has  been  2.  attempt  to  quantify  c h e m i c a l p r o p e r t i e s i n these ponds although a r e a ,  depth, v e g e t a t i o n , and s t a b i l i t y Table  little  This  of these ponds are r e p o r t e d  study d e a l s p r i m a r i l y with s e v e r a l  in  ponds i n the  lower mainland and one i n c e n t r a l B r i t i s h Columbia  and  further  d e s c r i p t i o n of these ponds i s given i n T a b l e 3. Daphnia arbitrarily plastic  fiulex  used  from f i e l d  in  the  samples  lab  experiments  and r e a r e d s e p a r a t e l y  v i a l s i n a 1:1 d i l u t i o n of pond water and  water. Animals were maintained at 15 C and hours of  and were fed on every t h i r d  unicellular  dechlorinated  Length,  at  ,  in  40  ml  dechlorinated  16-8  day an aguarium  algae, primarily C h l o r e l l a  light-dark  (lab) c u l t u r e  diluted  1:4  with  water.  Phenotypic determined  were chosen  by  width,  variation  at the f i r s t  morphological and  head  shape); and l e n g t h of t a i l  and  diameter  reproductive instar  physiological  measurements.  ( i n d i c a t o r s of body s i z e  s p i n e and eye diameter  was  (presumed  and to  11  Figure 1:Location of Vancouver and in W i l l i a m s Lake.  ponds in the lower mainland the I n t e r i o r o f B r i t i s h Columbia  near near  12  Table 2 :  Summary of the a v a i l a b l e environmental data f o r the lakes i n t h i s study.  Daphnia sp. UBC Research Forest * Eunice Placid Gwendoline Katherine  E l e v . (m)  S.A. (ha)  depth (m)  cutthroat t r o u t  carp D. l a e v i s  480 510 522 505  18.2 1.6 13.0 20'. 7  42 7 27 29  30  <.05  @2  10  <.01  il  Stability  6.4 5.5-6.6 6.6 6.6  permanent  6.5-6.7 6.5-6.7 6.4  temporary  v D. pulex  6.1 6.1 6.0-6.1 6.2- 6.3 6.3- 6.4  P3  PA P5 P6 P8 Mcleans  6.0  UBC Campus Library Bumaby Deer Lake Williams Lake ** NR Box 22  **  pH  D. rosea  UBC Campus Nitobe Gardens Langley Pl-A P2-A P7 Riggs Newhouse PI P2  Fish  * Northcote and C l a r o t t o , 1975 Topping, 1969  trout  30  <.01  100  36.0  6.8-7.0  945 945  5.06  8.1-8.6  permanent  temporary  < 1  permanent  T a b l e 3 : A summary o f t h e p h y s i c a l c h e m i c a l d a t a f o r t h e P e t e r s o n ponds and NR. D a t e s o f c o l l e c t i o n a r e i n d i c a t e d i n p a r e n t h e s e s f r o m 1976.  Daphnia sp. P1A/P2A  laevis  temp.  umho  (C)  PP (4/26) 13.2  (4/26)  14-17  (5/10)  50  (4/26)  6.1  m  _PJL  P2  pulex  (5/19) 0.6 (6/18). 0.8 (6/23) 1.4  (5/19) (6/8) (6/23)  7-7.5 10 9  (5/10)  35  (4/26) (5/10)  6.1' 6.1  P3  pulex  (4/26) (5/19)  16 17  (5/10)  38  (4/26) (5/10)  6.1 6.1  P4  pulex  (4/26) 9.2 (5/19) 8.1 1.4 (4/26) 1.4 (5/19) 1.2 (6/8) 1.4 (6/23) 2.8  (4/26) (5/19) (6/8) (6/23)  10-10.5 7.5 9 9  (5/10)  . 38  (4/26) (5/10)  6.0 6.1  P5  pulex  (4/26) 1.3 (5/19) 1.2  (4/26) (5/19) (6/8)  10.5 8 11  (5/10)  35  (4/26) .(5/10)  6.4 6.4  P7  laevis  (4/26) 4.5  (4/26) (5/19)  12-15 11.5-15  (5/10)  30  (5/10)  6.4  P8  pulex  (5/19) 4.7 (6/8) 3.6 (6/23) 2.2  (5/19) (6/8) (6/23)  7.5 9 9-9.5  PI  pulex  (6/8) 0.9 (6/23) 1.2  (6/8) (6/23)  11 9.5  NR *  pulex  (5/12/66) 4.4 (7/27/66) 1.2  (5/12/66) (7/26/66)  (5/12/66) (7/27/66)  1, 182 1,485  (5/12/66) (7/27/66)  8.6 8.1  * NR d a t a f r o m T o p p i n g s , 1969  14.4 16.4-18.9  15  be  ecologically  (Zaret,  1972;  micrometer and  are  eggs  important Dodson,  at  50x  1974)  microns  the  primaparous  physiological  variability,  individuals  from  ponds  were  measured:  total  eggs/female,  Genotypic measured  by  technigues Fifteen field  x the 6  i n an H  mm  slit  of  pieces in a  buffer.  of  was  NR,  described starch  described  the  from  of  pH  buffer  number  The  Electrostarch  Three  buffer  types  (ES-1,  (GOT-1);  Poulik:  AKP-4) ,  acid  peptidase  ES-2), alkaline  {LAP-1,  dehydrogenase  glutamate  (MDH-1) ,  octanol  dehydrogenase  (SDH-1  and  phosphoglucose  XDH-2), and  indophenol  and  LAP-3,  glass  tissue  0.00 1 H HCl)  was  (10-1)).  EDTA, and  equivalent  absorbed  and  f o r 22  oxalate  to 9  x  into  a  Wise.) loci  5  and  (LiOH:  transaminase  AKP-2,  LAP-4);  into  inserted  Hadison,  dehydrogenase  isomerase  a  AP-2) , a n d  SDH-2) , x a n t h i n e  oxidase  pooled  (AKP-1,  and  using  from  to assay  and  was  c l o n e or  ( l o t 302,  and  LAP-2,  proteins  (1971).  paper  used  (AP-1  characters  eggs/brood.  with  with  were  phosphatase  comparing  a l .  M tris,  phosphatase  of  et  hand  filter  gel of  and  Selander  supernatant  1 Whatman  measure  broods/female,  structural  by  6.8  of  experiment  single  (0.01  number  electrophoresis  by  adjusted to  animals.  a  The  of  ocular  microscope  primary  number  12  avoidance an  physiological  gel  homogenized  amount  ( F i g . 2).  i n one  by  with  dissecting  the  five  12%  esterase  (AO-1)  instar  individuals  NADP w i t h  volume  text  growthrates,  to those  were  Wild  i n the  and  horizontal  similar  a  juveniles/female,  variation  samples  10-5  total  on  predator  measured  although,  mortality,  to twenty  grinder  P2  regards to  were  magnification  r e c o r d e d as  at  with  AKP-3,  leucine  and amino  EDTA:  malate  (ODH-1),  sorbitol  dehydrogenase  (PGI-1),  aldehyde  Buffers  and  (XDH-1 oxidase  stains  are  16  Figure  2:  Morphological  measures o f  phenotypic  variation.  17  18  farther described i n the appendix. To  determine  i f there  was  any  iotraclonal variability  individual animals were also assayed using a Tsuyuki There between  was  apparatus.  no detectable difference in electrophoretic mobility  siblings,  and  individuals  within  a  clone  were  subsequently pooled and run on the previously described systems.  19  RESULTS AND  Genotypic, discussed  phenotypic,  in three  the r e s u l t s  JPJLSGDSSI0J8  and  s e c t i o n s with  environmental results  and  variation  are  interpretation  of  i n c o r p o r a t e d i n t o each s e c t i o n .  Electrophoresis  Three assayed of 35  species  electrophoretically  Daphnia p u l e x km  from  individuals animals animals  and  from  Williams  monomorphic and  loci.  o f Daphnia  NR  for  and  Box  in  variable  Activity  assayed  at polymorphic l o c i  p a t t e r n s of these frequencies  variable  loci.  Daphnia pulex  mainland  (P2,  months and  P4,  a l l loci  Similarly  and  or  P8)  %  three  ponds  i n the  22  too  few  polymorphic 3,  and  the  LAP  3  complex  attempt  in  NR  Box  made t o  heterozygosity/individual  from  the  at  lower  were s a m p l e d s e m i - m o n t h l y f o r f o u r period.  were monomorphic i n a l l p o p u l a t i o n s  i n d i v i d u a l s from P l a c i d  populations  been no  were monomorphic d u r i n g t h i s  Daphnia r o s e a  assayed.  of  were  4).  however  because  Creek,  palex  (Table  measurment o f %  and  exception  Daphnia  of a l l l o c i  has  ponds  the  PGI-1, AKP-2 and  there  22  ponds n e a r R i s k e  populations  however,  loci  gene  other  all  for accurate  measure  although  (two  f o r 38%  H i s shown i n F i g u r e 3,  banding  22  were a l s o v a r i a b l e f o r t h e same l o c i , were  from  12 enzymes. With  Lake) a l l i n d i v i d u a l s o f  identical  were  were c o l l e c t e d  Lake d i f f e r e d  slightly  m o b i l i t y of s e v e r a l a l l e l e s  from  at the  the AKP,  20  Table 4  :  Per cent monomorphic l o c i and number o f i n d i v i d u a l s assayed f o r each p o p u l a t i o n and each s p e c i e s .  specxes  populations sampled  Daphnia rosea  UBC Research F o r e s t : Eunice Placid Gwendoline Katherine UBC campus N i t o b e Gardens  Daphnia laevis  Langley: Pl-A P2-A P-7 Riggs Newhouse  Daphnia pulex  Langley: PI P2 P3  P4 P5 P6 P8 Mcleans UBC campus: Library Burnaby: Deer Lake W i l l i a m s Lake: Near Roundup Box 22  number o f individuals  number of l o c i  monomorphic loci (%)  18  100%  12  100%  18  100%  18  62%  93 240 124 56 105  40 82 18 55 21  132 250 50 342 110 41 170 96 26 90 153 52  21  F i g u r e 3: E l e c t r o p h o r e t i c loci.  p o l y m o r p h i s m a t t h e AKP,  ES, and  LAP  ES  23  AP,  and  Daphnia in  the  LAP laevis  five  The  whether species  (Tables  were  also  populations  three  described  species  i n Tables  small  4  however,  assayed  and  consistent  and  identical  5).  another  at  difficult  a  function  of  the  several to  multidimensional are  needed  to  and  are  detailed  gels,  or  determine  loci  determine due  technique.  in a l l gels  differences. Further  seguencing  species in  of  four  identified  as  S.  differences in  These  and  species,  These  assumed studies  amino  the  to  acid  magnitude  differences.  Two  by  a l l loci  4  one  third  e l e c t r o p h o r e t i c mobility are  are  focusing,  A  at  i s  are  isoelectric  assayed  It  or  using  these  from  5).  species  of  5).  (Tables  differed  biochemical  and  and  monomorphic  be  composition  4  differences in  differences  differences, to  loci  results  are  The  s e r r u l a t u s and  S.  mobility  intermediate  not  Simocephalus  two  species,  vetulus*  banding only  reproducing,  of  hybrid  of  the the  because  but  species  were  also  tentatively be  at  recognized  several  loci.  Simocephalus  because  1)  species,  biochemical two  could  patterns  d i f f e r e n c e s between  hybrid or  and  interesting  biochemical  occassional  cladoceran,  populations.  parthenogenetically consistent  another  types  (Krepp,  are  there and  are  2)  an  suggests  an  unpublished  da  ta) .  No  obvious  homogeneity  of  Electrophoretic polymorphisms the  observed  explanation each  species  differences observed  monomorphism  in of  exists  i n 20 were  NH  and  lower  for  ponds i n  electrophoretic  the  lower  mainland.  detected  among  species  and  Box  i t i s unlikely  that  22  so  mainland  populations  i s  a  Table ->  locus  : Numerical designations f o r a l l e l e s measured from the o r i g i n (mm) and a l l e l e frequencies (%) f o r three species of Daphnia.  JK_ rosea D. rosea ( a l l pops.)* (Placid)  D. l a e v i s ( a l l pops.)  D. pulex D. pulex ( a l l pops.)**(Near Roundup)  PGI-1  30 (100)  30 (100)  26 (100)  30 (100)  30 (80) 31 (20)  GOT-1  43 (100)  43 (100)  40 (100)  43 (100)  43 (100)  XDH-1 2^  32 (100) 30 (100)  32 (100) 30 (100)  34 (100) 28 (100)  32 (100) 30 (100)  32 (100) 30 (100)  15 (100)  15 (100)  32 (100) 25 (100)  32 (100) 25 (100)  IDH-1  — —  — —  — —  SDH-1 2  32 (100) 23 (100)  32 (100) 23 (100)  33 (100)  AO-1  34 (100)  34 (100)  35 (100)  34 (100)  34 (100)  0DH-1  36 (100)  36 (100)  36 (100)  36 (100)  36 (100)  MDH-1  30 (100)  30 (100)  30 (100)  30 (100)  AKP-1 2 3 4  71 67 57 53  73 67 58 54  68 (100) 50 (100)  polymorphic polymorphic  AP-1 2  71 (100)  ES-1 2  (100) (100) (100) (100)  (100) (100) (100) (100)  — —  — —  67 (100) 57 (100) — —  ' ——  74 (100) 67 (100)  68 (100)  80 (100) 76 (100)  80 (100) 76 (100)  80 (100) 76 (100)  80 (100) 74 (100)  polymorphic polymorphic  LAP-1 2 3  70 (100)  70 (100)  70 (100)  70 (100)  4  53 (100)  70 62 57 54 37 50  —  — — — —  — — — —  55 (100)  * excluding P l a c i d ** excluding Near Roundup  — —  — — — —  55 (100)  68 (100) 63 (100)  — — — —  .  55 (100)  — —  (100) (100) (36) (64) (79) (21)  25  function  of  the  electrophoretic  technique.  Alternative  e x p l a n t a t i o n s f o r t h e m a i n t e n a n c e o f v a r i a t i o n i n NR variation  in  temporal  a l l  and  directional  other  spatial or  ponds  stability  stabilizing  parameters such as  may  relate variability  of  the  selection,  the f r e q u e n c y  of mutation.  considered The  and  NR  may  suggest  variation  among  to  population  populations,  variability  inherent  i n these  individuals  electrophoretically an  C o m p a r i s o n Of  has  identical  been  and  are f u r t h e r  mainland  d i f f e r e n c e s i n the  populations  polymorphic  P2, P4,  Phenotypic ponds,  and  egg  variances,  P4,  (NR)  and  P5,  951  populations are given i n Table  and  egg  and  three P5,  (P2)  and  measured i n Daphnia c o l l e c t e d i n the lower  confidence 6.  and  Data  mainland,  by  important  limits  Even i n t h e s e  s i m i l a r p o n d s , a one-way a n a l y s i s o f v a r i a n c e length  phenotypic  population.  number, b o t h e c o l o g i c a l l y and  their  for  monomorphic  P5; F i e l d  v a r i a t i o n was P2,  body l e n g t h and  And  compared  p o p u l a t i o n s , P2, P4,  electrophoretically  electrophoretically  body  to  to adapt t o t h e environment. For t h i s reason  variation  Means,  other  These e x p l a n a t i o n s of  amount o f p h e n o t y p i c  three  and/or  the  i n the f i n a l d i s c u s s i o n .  populations  between  environment,  e l e c t r o p h o r e t i c d i f f e r e n c e s between t h e l o w e r  ability  to  of  of s e x u a l r e p r o d u c t i o n , r a t e of  r e p r o d u c t i o n , r a t e of recruitment from rate  or l a c k  for  from  scoring traits.  the  three  three  physically  (ANOVA)  comparing  number i n d i c a t e s s i g n i f i c a n t d i f f e r e n c e s  Table  6 : Estimates of the mean, variance and 95% confidence limits for body length and egg number for P2, P4, and P5 field populations.  population  N  body length mean±confidence limits variance  log body length meaniconfidence limits variance  egg number meaniconfidence limits variance  P2  140  1.99x10' 136.97  3.29 ± .012 6.18 xlO 3  8.1 ± 1.43 74.54  P4  120  2.57 xlO" 219.88  3.40 ± .014 6.30 xl0~3  13.0 ± 2.24 157.26  P5  109  2.30 xlO' 134.59  3.36 ± .012 4.45 xl0"3  15.3.+ 2.14 129.93  N3 ON  27  among p o p u l a t i o n s genetically that  f o r both  similar  organisms a r e  electrophoresis  phenotypic amount  c h a r a c t e r s . This suggests  does  not  variability.  A third  phenotypic  variation  of  and  i n f l u e n c e d by e n v i r o n m e n t a l  or  by  age  differences  phenotypically measure  explanation within  in field  in  these  If number  animals  three  among  flexible,  that  the  among  due  populations  i n P2, P4, and P5.  o f body l e n g t h  i n d i c a t e extreme v a r i a t i o n  i n the variances to  of o v e r a l l  1) a d e c r e a s e single for from  body  large  non-genetic  among  (Fig.H to individuals  environmental  and means o f l e n g t h  genetic  i n variance  in  variability, lab  and  egg  d i f f e r e n c e s o r age v a r i a t i o n  among i n d i v i d u a l s and i f t h e e l e c t r o p h o r e t i c v a r i a t i o n indication  or  genetic basis of  ponds may be  individuals  that  populations.  variation is  i s  heterogeneity  Histograms d e s c r i b i n g the d i s t r i b u t i o n 6)  the  either  i s a good  then  one would  populations  measured  expect at  a  p h y s i o l o g i c a l age, a n d 2) a c o n v e r g e n c e t o a common mean length  and f o r egg number  P2, P4, and P5.  in  lab  reared  populations  28  F i g u r e 4: D i s t r i b u t i o n of populations of Daphnia  body pulex  lengths from P2,  in  field  and  lab  30  Field  20|-  0  40  Lab  30  20  0 1.2  1.5  ,lll.limiLI»ulL.II>LllllllJl.L —  2.0  Body Length  J , ! , , , , , ! , , , , ^ .  2.5  rnm  3.0  30  Figure 5 :Distribution of body lengths p o p u l a t i o n s o f D a p h n i a p u l e x from PU.  in  field  and  lab  32  F i g u r e 6: D i s t r i b u t i o n of p o p u l a t i o n s of Daphnia  body lengths in p u l e x f r o m P5.  field  and  lab  20-  Field  10  r  0 Lab  30  201-  10  ol1.0  1.5  2.0  Body Length  mm  2 . 5  34  C o m p a r i s o n Of  To  £4,  And  determine  individuals  and  phenotypic  controlled produced  P2,  the  Lab  impact  environmental  P4,  and  And  of  the  lab  separated  and  measured a t t h e  from  into  age  were  reared  each  individual  diameter,  differences  length  on  the  separate  vials body  field  and  of  from  field  vials  under  the f i r s t  these  among  amount  collected  in  of  primaparous i n s t a r :  head  Data  heterogeneity  animals  P5  Field  l a b c o n d i t i o n s . I n d i v i d u a l s from in  diameter,  P5z  variability,  populations  further  P2,  generation  animals  six  were  characters  l e n g t h , body w i d t h ,  of t a i l  s p i n e , and  eye  number  of  {Fig.  4  eggs.  Histograms d e s c r i b i n g the to in  6}  i n l a b animals  field  a r e compared  animals.  It  a n a l y s i s that animals show c o n s i d e r a b l y the  field  differed  and  distribution  is  evident  reared  less  lab populations  field  variation  lab populations  than  same ponds. The 8)  indicates  the  lab populations  and  between  the  variance  log  of  the t o t a l  contain 6%  because of  body l e n g t h  show  reared  statistical  lab  conditions  with  an  f o r egg  F test  number  significantly  to f i e l d  variation  observed 13%  for  and  greater from  the  (Table  i n the body  of  (Table  variance  field length  number. However, t o a v o i d b i a s i n g  d i f f e r e n c e s i n mean body  (Lewontin,  lengths  to  from i n d i v i d u a l s  between 5 and  f o r egg  of  parameter. Variances  were compared  of lab variance  that of  1 and  in this  populations  ratio  prior  controlled  f o r body l e n g t h and  7) . As e x p e c t e d  lengths  distribution  even  under  variation  significantly  to the  of  1966)  was  length  ,  the  compared. A comparison  Table 7  : Comparison o f l a b and f i e l d v a r i a n c e s o f body l e n g t h and egg number i n P2, P4, and P5. A l l v a l u e s a r e s i g n i f i c a n t a t P < . 0 1 .  population  body l e n g t h V  field  /  V  lab  P2  F  139 155  P4  F  119 75 = 17.43  P5  F  108 163  10.13  7.91  l o g body l e n g t h V  field  F  139 155  /  =  V  lab  5  '  6  egg number V  2  field  /  V  lab  F  139 15.89 155 ~  F ^  = 7.00  F  119 75  F  = 3 97  F  108 31.39 163 ~  1 0 8  163  J  ,  y  /  68.20  LO  36  Table 8  : Comparison of lab and f i e l d variances of body length and number (% variation) i n P2, P4, and P5.  population  body length  l o g body length  egg number  V  V  V  / V lab' field  /V lab' f i e l d  /V lab' f i e l d  P2  9.9%  17.8%  6-3%  P4  5.7%  14.3%  1.5%  P5  12.6%  25.2%  3.2%  37  of  variances  relative  of log  variation  populations  (Table  These  data  values  also  indicate  (14  25%)  i n lab populations  -  significantly  less  than  field  8) . ,  suggest  variation  i n a natural  factors:  age  that  a  population  differences  large  amount  of  i s attributable  among  individuals  observed  to  and  non-genetic  environmental  heterogeneity.  and  This  i s similarly  egg  number  There egg  were  9  i n  variances  again  smaller may  be  particularly than  lab  may  with  as  also  and f i e l d  to  older  age  eggs  tend  a d u l t s . The r e d u c t i o n be due t o e n v i r o n m e n t a l  the l a b environment  i s poorer  than  from  and  mean  each  pond.  are given  field  were  to have  on  the This  individuals  larger length  differences the field  i n Table  individuals.  among  i n body  length  7 and 8 ) .  length  individuals  differences  individuals  body  intervals  than  of  (Figures  populations  Lab reared  fewer  values  populations  and 95% c o n f i d e n c e  due  primaparous  number if  the  mean  d i f f e r e n c e s i n mean  f o r the l a b populations.  average  i n comparing  i n l a b and f i e l d  significant  number  Heans,  true  clutches and  egg  particularly  environment.  38  Figure 7: field  Means and 9 5 % (• ) and l a b  c o n f i d e n c e l i m i t s f o r body l e n g t h i n ) p o p u l a t i o n s f r o m P 2 , P I , and P5.  Body  Length mm  CO  40  F i g u r e 8: Means and 9 5 % c o n f i d e n c e l i m i t s f o r egg number i n f i e l d <• ) and l a b (^) p o p u l a t i o n s from P2, P4, and P5.  Egg Number oi  o  I  •  1  •  -J.  cn  ro o  42  Table 9  : Estimates of the mean, variance, and 95% confidence intervals for P2, P4, and P5 lab populations. Sample sizes are indicated in parentheses.  P2 (155)  P4 (76)  P5 (164)  body length  1.56 xlO ± 18 13.51  1.62 xlO ± 25 12.61  1.71 xlOi 17.01  log length  3.19 ± .006 1.10 xl0-3  3.21 ± .007 .90 xl0-3  3.23 + 006 1.12 xlOi-3  egg number  2.67 ± .340 4.69  2.47 ± .342 2.31  2.75 4.14  +  312  log egg number  .106 ± .109 .479  .223 ± .119 .279  .185 .425  +  101  variable 1  -.045 ± .011 .005  -.004 ± .016 .005  .046 . .007  +  013  •variable 2  -.021 ± .005 .001  -.027 ± .008 .001  .008 .004  +  009  variable 3  .025 ± .006 .002  -.007 ± -.008 .001  -.021 ± .007 .002  3  3  3  ±20  a3 Comparison  O f P 2 , PJ£,ftng P 5 : L a b D a t a  Since  age  responsible in  field  and  differences  e g g number  genetically  one  among  might  expect  the three  populations  s i m i l a r as suggested  i s  true  for  mean  to  mean  eggs/female  populations,  significantly.  This  explained  a  by  environmental undetected and  body  body  comparisons  of  one might  after o r i n NH  mean  neither  body  differ may  be  length  to  populations  i n  egg  differences  number i n  each  i n the environment. I t  be i n s e n s i t i v e t o  closely  lengths  be v e r y  immediate  sensitive to  associated  with  the  of  mean  parent.  only i n P2  may  and  body  length  on  no  converges  d i f f e r e n c e s among  e g g n u m b e r may  environment  demonstrated  effect  t o changes  length  whereas  i s the case  lengths  experiments  body  change  of the  this  t o respond  that  o f body  intrinsic  were  however,  . T h e differences  suggest  ability  immediate  If  maternal  9) . Mean  P5,  of convergence  there  Egg number  (Table and  or to genetic  length  possible  physiology  P<4,  residual  change  environmental the  lack  lengths  i f P 2 , P 4 , a n d P5 a r e  populations.  by e l e c t r o p h o r e s i s  characters* seems  P2,  variation  o f mean  egg number i n w h i c h  among  o f 2.7  are  by t h e e l e c t r o p h o r e s i s .  differences  a common  effects  phenotypic  a convergence  significant  among  environmental  f o r 70 t o 9 0 % o f t h e o b s e r v e d  animals,  This  and  P2  expect  a convergence  a number o f b r o o d s . i n four  This  generations  length  i n each  n o r NR  showed  population any c h a n g e  has n o t been  i n the i n two i n  mean  lab. In separate length  44  between  experiments;  likewise  common mean. I t may be a r g u e d the  populations  that  there  that  there  that t h i s  was  no c o n v e r g e n c e  was n o t l o n g  enough  large  differences  in  the  two  populations  i t i s u n r e a s o n a b l e t o e x p e c t a n y c o n v e r g e n c e . More  rigorous  wide  phenotype  in  that  or  environment, fairly  range  selection  which s u g g e s t s  for  t o respond t o the change i n t h e environment o r  a r e such  however, t h e  to a  a  of the  a  phenotypes lab  single  constant  particularly  reflects  environment.  genotype  fitness  a  likely, lack  of  There i s nothing  codes  for  a  single  ( K o j i m a , 1971) i n any g i v e n  i f the expression  of the  genotype  is  plastic.  Differences alternatively  be  electrophoresis.  in  mean  due  to  length genetic  among differences  This possibility w i l l  t h e next s e c t i o n based  populations  may  undetected  by  be f u r t h e r c o n s i d e r e d i n  on c o m p a r i s o n s o f i n t e r -  and  intraclonal  variation.  Comparisons  Of £ 2 , £ 4 , And £ 5 ^ I n t e r  Speculation variation  i n these  environmental and  field  sufficient  on  the  organisms  has  and maintenance relied  on  and e l e c t r o p h o r e t i c v a r i a t i o n  populations. to  source  And I n t r a c l o n a l  account  Since neither for  Variation  o f phenotypic  explanations  i n comparison  of l a b  of these explanations i s  a l l phenotypic  variability  populations i t i s necessary t o look a t phenotypic v a r i a t i o n finer  level of resolution,  siblings  i s known.  of  within clones,  among at a  where t h e g e n o t y p e s o f  45  InterP5  and i n t r a c l o n a l  and t h e a n a l y s i s i s d e s c r i b e d  components within  analysis  each  populations, one  way  within of %  variation  4) c a l c u l a t i o n  clones  t h e components  among  to  body  principle  for  clones  means  among  variation  and absolute and  a nested  within  from  a  variation  5)  calculation  ANOVA  t o determine  a n d among  clones  and  o f 18 t o 21 c l o n e s  from  components  length  diameter,  individual  instar  analysis  1 i s a measure  and i s t h e r e f o r e  spine  important  and Dodson,  variables  a n d body  variation  rather  eye with  1965; Z a r e t , length  than  and  f o rthe s i x characters data  was p o o l e d  PCA  pooled  b y PCA  variables  the  f o r 95%  o f body  were  diameter respect  length,  the individual  body  of  total width,  body  size due t o  are  presumably  predator  avoidance  1972; Dodson,  were used  the  of variation  which to  morphological of  an i n d i c a t o r  2 and 3 a r e composed and  vials  populations.  variables accounting  Variables  of t a i l  ecologically (Brooks  three  Variable  shape.  i n the lab i n  e g g number, a n d t h e t h r e e  Principle  head  each  The morphological  the three  into  from  reproductive  t o compare  variation.  and  reared  described.  length,  measures  and  of  of  population, from  1)  means  comparison  variation  siblings  at the f i r s t  previously  used  twenty  P 4 , a n d P5 w e r e  measured  and  of  % variation  of variation  and a b s o l u t e  sections:  o f components  i n each  i n P2, P4, and  populations.  Ten P2,  3)  t o determine  a n d among  i n five  2) c o m p a r i s o n  population,  ANOVA  variation  (PCA),  i s measured  a s measures  1974). of  morphological  The  PCA  morphological characters i n  46  all  further  Each  analyses.  character  population  using  differences characters the  that  among (Figure  clones 9). This  Each  and  within result  data.  That  be g e n e t i c among  clones  and  was  there  and t h e t h r e e  clones  there each  were  are  identical  are  real  sufficient  also were  compared  among  that  produce  significant  the  differences  three i n body  PCA v a r i a b l e s among p o p u l a t i o n s . / T h e r e  As s u g g e s t e d  i n the previous  be  due t o t h e r a t e  to  genetic  of response  differences.  electrophoresis  o r 2)  clones.  P5.  may  suggests  to  d i f f e r e n c e i n mean e g g n u m b e r among  there  by  phenotypic  clones  significant  that  f o ra l l  unpredicted  no  electrophoretically  each  significant  population  i s completely there  within  d i f f e r e n c e s among c l o n e s  d i f f e r e n c e s among  character  populations length  may  effects  significant  ANOVA  among  among e l e c t r o p h o r e t i c a l l y  there  maternal  compared  one-way  electrophoretic  differences 1)  a  was  which  t o changes  Information  identical be  section these  clones  genetic are  P2, P4, and  differences  may  i n the environment  on  the  comparison  seems t o s u p p o r t  differences  responsible  was  or of  the idea  undetected  by  f o r the differences i n  phenotype.  Components 1969)  from  provide within  a Model  estimates  I I ANOVA  within  individuals  (Becker, were  1967;  computed  of the % variation  a n d among c l o n e s .  individuals in  of variation  clones among  Less  variation  (which  Sokal  f o r each  attributable i s  which  Rohlf,  character to  expected  are genetically  clones,  and  variation among  identical)  although  and  they  i n than are  47  Figure 9: Means and 95% confidence limits f o r the p r i n c i p a l component v a r i a b l e s o f P2, P4, and P5.  three  b  b  A  INO  Variable 1 b o o o  b  rv>  TJ ro  2 TJ Ol  Variable2  IS TJ TJ cn  Variable 3 "D ro  TJ cn  h H  I—e  -H  b A  b  cn  49  electrophoretically  identical,  are not  necessarily  genetically  identical.  This  expectation  of v a r i a t i o n w i t h i n length each (Table of is  and among c l o n e s .  occurs  10)..This large  the s t a t i s t i c a l the  clone actually  represent  effects  large  amount  the  reduce  as  within  well  clone  as  any  any  variation unexplained  'true*  variation  within  however,  may  d e g r e e o f v a r i a t i o n among g e n e t i c a l l y  due  to  non-genetic  microhabitat  factors  differences  Based expect  phenotypic  phenotypic  sibs  such  as  among  vials  even  among  of s t a t i s t i c a l  biases,  of  identical  on t h e s i m i l a r i t y similar  the  significant  among  by  of  supporting  individuals  electrophoretically  an  F  and  among  inter-  the test  clones  and  phenotypic suggest  among  one  intraclonal variation there  i s no  variation for  the e l e c t r o p h o r e t i c data and  among  i n the previous  and i n t r a c l o n a l  within  identical.  differences  described  within  amounts  difference i n inter-  characters, that  clones  mean  clones  v a r i a t i o n . Comparisons of  and  variation  independent  importance  electrophoretically  infers  error)  of  may  several  the w i t h i n c l o n e  clones  development.  identical  within  may be a f u n c t i o n  or  genetically  section.  clones  a large  maternal  A  v a r i a t i o n within  The  individuals  variation for  t h a n among  o f t h e ANOVA and i n c l u d e s  identical  affecting  %  rather  (experimental  variation.  greater  o f body  clones  technique i n that  r e s i d u a l term  variation  would  within  however, i n c o m p a r i s o n s  Hith the exception  ( VI) i n P4 t h e  and body s i z e character  i s not s u p p o r t e d ,  clones  which are  50  Table 10 : Comparison of w i t h i n and among clone v a r i a t i o n i n P2, P4, and P5. Variances and % v a r i a t i o n are given.  P2  P4  P5  body l e n g t h * within among  8.59 5.17  (62.4%) (37.6%)  5.40 7.58  (41.6%) (58.4%)  11.75 5.54  (68.0%) (32.0%)  egg number within among  3.06 1.71  (64.2%) (35.8%)  1.68 .65  (72.0%) (28.0%)  2.92 1.28  (69.5%) (30.5%)  variable 1 within among  3.60x10 ^ (67.0%) 1.77x10 (33.0%)  2.03xl0_^ (39.8%) 3.07x10 (60.2%)  4.80xl0_^ (69.9%) 2.07x10 (30.1%)  variable 2 within among  .814x10";? (69.3%) ,36 xlO (30.7%)  ,954xl0_^ .23 xlO  (80.6%) (19.4%)  3.18xl0_^ (85.3%) .55 xlO (14.7%)  variable 3 within among  L.50x10"^ (86.7%) ,23 x l 0 " (13.3%)  ,902xl0_^ (72.8%) ,35 xlO (26.2%)  1.56xl0_;r (71.9%) .61 xlO (28.1%)  J  J  J  * Body length i s measured i n microns and variances associated with body length w i t h i n and among clones are x 10 .  51  To  e v a l u a t e the amount of a d d i t i o n a l  p o p u l a t i o n s , components o f v a r i a t i o n nested and  ANOVA p a r t i t i o n i n g  among  v a r i a n c e s f o r each  character  within  c l o n e s and among p o p u l a t i o n s . For a l l c h a r a c t e r s the  of  and  clones  and  with  (Table 1 1 ) . The amount  of  variation  among c l o n e s i s q u a l i t a t i v e l y s i m i l a r t o the amount  of v a r i a t i o n from the one-way ANOVA. Again,  the v a r i a t i o n  c l o n e s may be a f u n c t i o n of the ANOVA,  which  term i n c l u d e s both non-genetic variation  within  clones  may  in  and unexplained be  the  one  variation  would  expect  comparable  v a r i a t i o n , o r the  g e n e t i c . As suggested  amounts  number)  variation  of  by the which  morphological  among c l o n e s and among p o p u l a t i o n s . Hence, even though  p o p u l a t i o n s d i f f e r e d i n mean values f o r a l l egg  within  residual  e l e c t r o p h o r e s i s these p o p u l a t i o n s may be very s i m i l a r , i n case  the  egg number, % v a r i a t i o n among p o p u l a t i o n s exceeds  the v a r i a t i o n among c l o n e s within  found among  were a l s o determined from a  g r e a t e s t % v a r i a t i o n again o c c u r s w i t h i n exception  variation  they  appear  to  characters  (except  be very s i m i l a r i n t h e amount o f  w i t h i n and among c l o n e s and p o p u l a t i o n s .  Table  11: A comparison o f v a r i a t i o n w i t h i n and among c l o n e s and among p o p u l a t i o n s P2, P4, and P5. V a r i a n c e s and % v a r i a t i o n a r e l i s t e d f o r each c h a r a c t e r .  v a r i a t i o n w i t h i n clones  body l e n g t h  *  v a r i a t i o n among clones  v a r i a t i o n among p o p u l a t i o n s  9.08  (41.0%)  5.66  (25.5%)  7.42  (33.5%)  egg number  2.75  (68.5%)  1.26  (31.5%)  <0  (0.0%)  variable  1  •3 3.81x10"  (45.1%)  •3 2.18x10"  (25.8%)  •3 2.45x10"  (29.1%)  variable  2  •3 1.86x10"  (67.5%)  •3 .374x10"  (13.5%)  •3 .523x10"  U9.0%},  variable  3  •3 1.42x10"  (57.9%)  •3 .390x10"  (15.9%)  •3 .645x10"  (26.2%)  * v a r i a n c e s a s s o c i a t e d w i t h body l e n g t h w i t h i n and among c l o n e s and among p o p u l a t i o n s a r e x 10 .  53  C o m p a r i s o n Of P2, P4, And P 5 i Summary  P2,  P4, and P5 a r e s m a l l ,  physically similar  within  10 m o f one a n o t h e r i n L a n g l e y ,  these  three  loci  differences  characters  (except  populations, within  each  inherent with be  2)  been  reared  i n Table  values  for  populations)  populations,  a l l suggest there  and among p o p u l a t i o n s  1)  and are  although,  this  individuals.  tentatively  large  variances  individuals. genetically populations.  12.  phenotypic  among  field  3) among  clones  real  differences  which a r e n o t c o n s i s t e n t  Mean d i f f e r e n c e s i n p h e n o t y p e among  may  field  i s not a p r a c t i c a l e x p l a n a t i o n i n  Explanations  characters  f o r these  differences  have  of  i n response t o the l a b environment, phenotypic  undetected indicate  environmental  l a b and  s u g g e s t e d as due t o 1) s l o w r a t e o f change o f  degree  populations  ,  a l l  a t t r i b u t e d to environmental d i f f e r e n c e s  differences  a  lab  the e l e c t r o p h o r e t i c data.  morphological a  mean  egg number i n  population  populations, lab  a r e summarized  in  among  within  largely  B.C. A l l i n d i v i d u a l s from  b a s e d on c o m p a r i s o n s o f f i e l d  , and l a b p o p u l a t i o n s  The  located  ponds a r e e l e c t r o p h o r e t i c a l l y monomorphic a t t h e 16  examined. R e s u l t s  field  ponds  than  by  electrophoresis.  significantly field  effects A large  plasticity,  populations, and  variance  identical  sibs  This suggests that  wide r a n g e o f p h e n o t y p i c  less  age  within  expression  3)  genetic  Comparisons variation  presumably  differences  persists,  these  or  however, clones  in  2)  of  i n lab due  to  among  field  even  among  lab  reared  i n d i v i d u a l s are capable of from a s i n g l e g e n o t y p e .  54  Table  12: Summary o f the r e s u l t s  from comparisons o f P2, P4, and P5.  P2 FIELD DATA s i g . differences i n length and egg number among pop.  FIELD/LAB DATA reduced v a r i a n c e s and means f o r l e n g t h and egg number i n l a b population  LAB DATA electrophoretically homogeneous  i FIELD/LAB DATA reduced v a r i a n c e s and means f o r body l e n g t h and egg number i n l a b pop.  I  LAB DATA electrophoretical ly homogeneous  FIELD/LAB DATA reduced v a r i a n c e s and means f o r l e n g t h and egg # i n l a b pop.  LAB DATA electrophoretically homogeneous  mean body l e n g t h and PCA v a r i a b l e s s i g . d i f . among p o p u l a t i o n s no s i g . d i f . i n egg number among p o p u l a t i o n s s i g . d i f . among c l o n e s f o r a l l characters greatest % v a r i a t i o n w i t h i n clones f o r a l l characters  s i g . d i f . among c l o n e s f o r s i g . d i f . among a l l characters clones f o r a l l characters greatest % variation greatest % v a r i a t i o n w i t h i n c l o n e s f o r egg w i t h i n clones f o r a l l characters number,V2 and V3 greatest % v a r i a t i o n among c l o n e s f o r l e n g t h and VI greatest % v a r i a t i o n w i t h i n c l o n e s e x c e p t egg number (nested ANOVA) ! v a r i a n c e among c l o n e s l e s s than among pop. % v a r i a t i o n w i t h i n clones g r e a t e r than among pop. which i s g r e a t e r than among clones  55  The the  previous  relative  similarity data,  similarity of  the  particularly  variances,  and  populations  are  the  by  of  their  the  stability  apparent  individually not  by  relative  of  the  and  P2,  PH,  the  genetic  data  and  P5  data  and  genetic of  these  to changes  in  heterogeneity  but  This conclusion  and  relative  by the  comparisons  respond  plasticity. NR  justified  v a r i a t i o n suggest  b u f f e r e d and  the  are  among ponds. The  phenotypic  utilizing  to  P5  electrophoretic  e l e c t r o p h o r e s i s and  e x h i b i t i n g phenotypic  discussed  P4,  p h y s i c a l environment  the  environment  rather be  c o m p a r i s o n s o f P2,  will  to  environments i n the  the final  discussion.  Comparison  Of  P2  And  Comparisons  of  electrophoretic geographic  on  variation  than  T h a t i s , do  characters length,  an  and  justified  by  physical  and  ponds t o d e t e r m i n e i f t h e r e in  an  electrophoretically  elelctrophoretically  phenotypic  is  variation  invariant populations  o r on  genotypic  to e n v i r o n m e n t a l change?  separate  width,  five clones  f r o m P2  and  NR  v i a l s under c o n t r o l l e d l a b c o n d i t i o n s .  were measured a t  body  similarly  electrophoretically variant  amounts o f  t o adapt  in  are  variation  Twenty s i b s f r o m e a c h o f reared  NR  between  phenotypic  large  and  d i f f e r e n c e s between p o p u l a t i o n s  population  population. rely  P2  differences  more o r l e s s variant  NR  the  first  head d i a m t e r ,  reproductive eye  diamter,  instar: length  of  were Six body tail  56  spine, and number o f eggs. H o r p h o l o g i c a l c h a r a c t e r s were  pooled  by  number  principal  components  analysis.  Body length and egg  were a l s o measured once a week i n these both  populations  estimates number  had  died.  animals  until  t o t a l number of broods/female, 5) eggs/brood, and Since t o t a l eggs and  i n f l u e n c e d by the number of broods produced seems  that  these c h a r a c e t e r s ,  although  the f i t n e s s of the i n d i v i d u a l and variation.  For t h i s reason  % m o r t a l i t y as  variation.  length  Body  total juveniles i s by  important  Results  will  be  within each population  female  was  it  i n evaluating  indicators  overestimate  of  ratios actual  measured each week f o r each animal  p l o t t e d a g a i n s t l o g time. Growthrates were  from the slope of the  any  of the c l o n e , may  better  4)  6) % m o r t a l i t y  i t seems p r a c t i c a l to c o n s i d e r  of eggs/brood and  and  total  eggs/female, 3) t o t a l number of j u v e n i l e s / f e m a l e ,  {{eggs-juveniles)/eggs).  of  These l a t t e r measurements provide  of s i x a d d i t i o n a l parameters: 1) growthrate, 2)  of  1/2  then  determined  line. presented and  and  d i s c u s s e d f o r comparisons  f o r comparisons between p o p u l a t i o n s .  57  C o m p a r i s o n s Of £ 2 And NB; I n t r a p o p u l a t i o n  Results  and  experiment  are  comparisons  of  interpretation similar  P2  P4,  r  electrophoretically  to  of  the  those  and  P5.  figsalts  P2  data  described 1)  Daphnia  monomorphic and i d e n t i c a l  previous experiment.  2)  among  the  primaparous  clones  differences  i n l e n g t h , egg number, and t h e t h r e e  quality.  comparing  i n P2 i n d i c a t e d  interclonal eggs,  of eggs/brood,  and % m o r t a l i t y  in  significantly  among  clones  variation and t o t a l  P2  clones  total  g r e a t e r f o r egg eggs,  total  than % v a r i a t i o n  interpretation  of  among  the  applicable to these data.  in were  data,  a  significant  PCA  variables  t o be  larger  to  food  of growthrates, juveniles,  a l l characters  number  differed  e x c e p t g r o w t h r a t e and % m o r t a l i t y .  From a n a l y s i s o f t h e components o f v a r i a t i o n significantly  P2  ( T a b l e 13) p e r h a p s due  number o f b r o o d s / f e m a l e , t o t a l  broods,  from  t h e mean v a l u e s i n t h i s e x p e r i m e n t t e n d e d  In  this  previously  instar  of  than i n the p r e v i o u s experiment  in  to animals i n the  comparison  although  means  In  F o r £2  number, juveniles, clones  results  V2  the % v a r i a t i o n and  V3,  number  and % m o r t a l i t y  (Tables  described  14  and  previously  was of  within  15).  The  i s also  58  Table 13  : Estimates of means, variances, and 95% confidence i n t e r v a l s for P2 and NR.  P2  means  variances  NR .  means  variances  body length log length  1.63x 10 ± 32 3.21 ± .008  21.66x 10 1.52 x 10"'  2 . 1 9 x l 0 ±39 3.34 ± .008  35.33xl0 1.45 x 10  egg number log egg number  5.46 ± .63 .673 ± .054  8.40 .062  7.68 ± .64 .849 ± .038  9.36 .033  variable 1  -.135 ± .015  .005  .127 + .018  .007  variable 2  .021 ± .015  .005  .020 ± .015  .005  variable 3  -.003 ± .005  • 001  .003 ± .008  .001  growthrates log growthrates  990.9 ± 19.45 2.9 ± .02  31067.4 .01  1361 ± 85.52 3.1 ± .02  164672.7 .01  number broods log broods  7.64 ± .52 .86 ± .035  5.81 .027  10.74 ± .61 1.01 ± .034  8.53 .026  t o t a l eggs log eggs  57.99 ± 5.56 1.70 ± .056  661.7 .067  201 ± 16.04 2.26 ± .047  5827.4 .051  total juveniles log t o t a l j u v .  53.03 ± 5.24 1.66 ± .062  586.3 .083  182.9 ± 13.39 2.22 ± .045  4394.6 .046  eggs/brood log eggs/brood  7.71 ± .649 .848 ± .044  9.01 .041  18.24 ± .795 1.25 ± .021  14.32 .009  % mortality log % m o r t a l i t y  .098 ± .019 -1.44 ± .221  .008 1.05  .081 ± .009 -1.26 ± .136  .002 .416  3  3  3  3  Table 14: Comparisons of within and among clone variation in P2 and NR. Components of variation and % variation are given for each character and sample size indicated in parentheses.  within  P2 among  within  NR  among  body length  13.45 IO 56.5%  egg number  6.31 70.8%  2.60 29.2%  9.10 96.6%  0.32 3.4%  variable 1  2.94 56.6%  2.75 43.4%  -3 6.27x10' 83.7%  1.22xl0~ 16.3%  variable 2  -3 4.01x10' 95.6%  0.77x10'"3 4.6  -3 3.66x10' 65.0%  1.97xl0~ 35.0%  variable 3  -3 0.46x10' 81.5%  -3 0.10x10' 18.5%  -3 1.23x10' 87.6%  0.17xl0~ 12.4%  growthrates  144780 85.4%  24655 4.6%  31982 100.0%  -1152 0.0%  # broods  7.90 91.0%  .78 9 .0%  5.14 85.9%  .85 14.1%  total # eggs  5243.3 87.9%  724.1 12.1%  528.8 68.6%  241.6 31.4%  total # juveniles  3985.4 88.7%  507.3 11.3%  464.2 75.1%  '153.8 24.9%  eggs/brood  12.89 87.9%  1.77 12.1%  5.47 55.1% .  4.45 44,9%  %mortality  .0018 96.3%  .0000 3.7%  .0077 93.2%  .0006 6.8%  x  3  10.35 IO 45.5% x  3  29.59x 10 80.7%  3  5.83x 10 19.3%  3  3  3  3  T a b l e 15: R a t i o o f v a r i a n c e s w i t h i n and among c l o n e s i n P2 and NR from untransformed and l o g a r i t h m i c a l l y t r a n s f o r m e d d a t a .  P2  NR  F(81/81) witnxn  F(86/86) among 1.3 1.2  egg number  2.43  VI  1.26  *  ,  * *  5.00  growth r a t e l o g growth r a t e # broods l o g # broods t o t a l eggs l o g t o t a l eggs  v  among  4.17* 4.00 28.4 5.25  5.00  V3  witnm  *  body l e n g t h l o g body l e n g t h  V2  /  v  *  -27* -32  * 8.13  * 2.18* 4.35  *  1.80  *  * *  6.00 * 5.87 * 4.30 * 10.13* 8.50 * 7.24 * 10.70*  total juveniles log total juveniles  3-01* 4.20  7.86 * 13.90*  eggs/brood l o g eggs/brood  1.23* 1.61  7.28 * 11.00*  % mortality log % mortality  12.83* 94.00  d i v i s i o n by 0 219.4  *  P <.05  61  C o m p a r i s o n s Of P2 And NR: I n t r a p o p u l a t i o n l e s u l t s  O n l i k e P2, NR 28%  of  was e l e c t r o p h o r e t i c a l l y  a l l loci  significant  assayed.  differences  c h a r a c t e r s except  However, among  as  %  P2,  for  mortality.  were no d i f f e r e n c e s i n egg number among P2,  characters.  Estimates  for  population  t h e NR  of  differences  differences  among  variation  in  be  P2  was  and  related this  i n P2 d i f f e r e d  even though t h e y  the  single  tentatively  v a r i a b l e , however, i t electrophoretic with genotypic  These  seems  total  clones  of  inter-  and  have  inter-  variance  (Table  P5,  set of limits  i n Table  13.  electrophoretic  phenotypically  from  one  identical.  interpreted  as  plasticity  The  genetic  associated  may a l s o be h i g h l y  reasonable  because  t o a s s o c i a t e phenotypic  of  the  variation  diversity.  components o f v a r i a t i o n . the  to  individuals  more  heterogeneity  possibilities  comparisons  NR  and  confidence  were e l e c t r o p h o r e t i c a l l y  genotype.  there  was shown n o t t o be t h e  d i f f e r e n c e s among c l o n e s o r a s p h e n o t y p i c with  P4,  f o r each c h a r a c t e r  clones although  i n P2, i e . c l o n e s  another  may  phenotypic  i s unique t o t h i s  variance,  are given  were  e g g nummber among P2 c l o n e s ,  number  o f mean,  Interclonal  case  egg  there  Although  there  homogeneity  f o r 22 t o  a l l  significant  the  in  in  were  and  differences  polymorphic  clones  egg number and  F o r NR  in  and  further  intraclonal  explored  on c o m p a r i s o n s o f a b s o l u t e by  an F t e s t ,  from  variation  NR was w i t h i n c l o n e s r a t h e r t h a n  variation  in  variability  As i n P2, t h e g r e a t e s t %  14) a n d , b a s e d intraclonal  been  among  (not  within  of  %)  clone  62  variation  was  significantly  variation  for  a l l characters  One within  might  clones  interclonal greater  expect  in  P2  variation  between  P2  Tnterpopulation  differences V2  other  characters were  (populations similar)  unexpected. and  The  that  populations  are  in  characters  trend  and  between  differences  NR  i n P2  among  section.  It  to  animals  a  and  significant  P2,  P2  NR be  seems  Since and  P5  environmentally are  not  unique  more  and  It  seems  since  and  or  dramatic  P2.  the  since  populations  unlikely  induced.  that  the  reared these  A l t e r n a t i v e l y these  differential are  P2.  genetic  the  means For a l l  P4,  dissimilar in  NR.  than  and  and  may  be P2.  and  indicate  among  of  maintained  environmentally  which  next  may in  within  i s , however,  comparisons  due  than  larger  NR  in differences  been  there  the  Means  greater  electrophoretically  have  by  f o r a l l characters. , Only  differences  s e v e r a l broods.  NR  NR  electrophoretically  in  these  in  in  NRr  significantly  differences  were may  P2  was  are  clone  variation  suggested  i n the  And  NR  over  differences  £2  m o r t a l i t y were  in  differences  Of  populations  d i f f e r e n c e s were  lab  described  %  are  as  differences  means b e t w e e n  phenotypic the  however,  phenotypic  variances  unidirectional  possible  of  of  significant  these  amounts  comparisons NR  among  15).  in  and  which  than  clones  of  of  .05)  among  between  and  there  NR,  Comparisons  Comparisons  of  similar  and  (P  (Table  electrophoretic  Interpopulational clones  greater  incapable  rate of  of  change  responding  to  6  environmental  changes  Interpopulation  Comparisons  Comparisons variation  and  important  to  comparisons  of  variances.  A l l  comparisons  of  untransformed been  made  were  data.  compared  associated  number  of  greater  with  in  NR  i n  individuals  were  larger would  than  variability however,  be  P2  than  P2 more  was  total  and  The  NR,  greater body eggs  without  (Simpson, by  16)  and  based  than  NR.  V3,  do  mean  were  differences Lewontin,  taking  log  transforms  Variances  were  showed  no  These  that  NR  z o o l o g i c a l sense  expected  and  the  variance  populations. not  has  of  juveniles  essential  Roe,  and  growthrate,  characters  between  on  Variances  out the  on  absolute  variation  only  individuals  any  %  total  remaining  %  i t is  based  the are  of  length,  be  are  populations.  and  i t would  and  transformed  i n P2  however,  NR  of  of  characters  v a r i a b l e i n the since  clones  comparison  variances  individuals  that  variances  of  Intrapopulational  comparisons  (Table  P2.  variation  comparisons  test  untransformed  greater  argues  on  between  F  and  comparisons  among  clones  mortality  individuals:  also  an  both  and  statistical  differences in  differences  P2  %  or  among  Variances  absolute  within  untransformed  eggs/brood,  significant  than  and  11  with  associated  Ho  HR:  distinction. .  absolute  with  of  And  interpopulational the  within  comparisons  this  variation  generations.  include of  variances %  few  P2  variances  make  of  a  Of  comparisons  of  comparisons  in only  3  significantly that in  1960). of  the  variances functional Lewontin, data,  the  64  Table  16: Comparison o f v a r i a n c e s f o r NR and P2 (F t e s t ) . Degrees o f freedom: NR=86, P2=81  - body l e n g t h  *  F(86/81) = 1 .63  l o g body l e n g t h  egg number  F(86/81)= 1 .11  l o g egg number  variable 1  F(86/81)= 1 .53  variable 2  F(86/81) = 1 .14  variable 3 growth r a t e  * *  # of generations t o t a l # o f eggs  *  # of juveniles  *  # of eggs/genration  *  (eggs - j u v e n i l e s ) / e g g s  +  F(81/86) = 1 .05  +  F(81/85)= 1 .86  F(86/89) =2 .54  *  F(86/81) =5 .30  log  growth r a t e  F(86/81) = 1 .47  log  # generations  F(81/86) = 1 .02  F(86/81) =8 .81  log  t o t a l eggs  F(81/86) = 1 .33  F(86/81) = 7.50  log  # juveniles  F(86/81) = 1 .59  log  eggs/gen.  F(81/86) =4 .31  log  * P< .05 NR b e i n g g r e a t e r + P< .05 P2 b e i n g g r e a t e r  + +  (eggs-juv)/eggs  +  F(86/81) = 1 .62  F(81/86) = 1 .82 F(81/86) =4 .31 F(81/86) =2 .51  65  v a r i a n c e s , r e g a r d l e s s of the mean, a r e put on the same s c a l e and can  be compared s t a t i s t i c a l l y .  independent  of  mean  To estimate r e l a t i v e  differences  between  variability  populations  log  transforms o f the P2 and NR data s e r e compared with an F t e s t i n the  two  populations  comparisons variable  of  the  than  NR  (Lewontin, original  f o r egg  i n s t a r , t o t a l number  of  mortality.  eight  In  the  In  1966).  data, number  P2  sharp c o n t r a s t t o  was  at  relatively  the f i r s t  juveniles/female, transformed  reproductive  eggs/brood,  values  of  total  eggs  p o p u l a t i o n s . Only significantly  did  not  in  vary  significantly  comparing  relative  and  the  v a r i a n c e s of l o g values of body l e n g t h , t o t a l number of and  more  %  total  broods,  between the two  growthrates  was  NR  more v a r i a b l e than P2 (Table 16).  Having compared t h e t o t a l v a r i a n c e s between P2 and NE these variances  were  partitioned  into  components  i n t e r - and i n t r a c l o n a l v a r i a n c e s of between  populations  with  an  c l o n e v a r i a n c e s growthrates i n NR than  i n P2 although  significant  at  P<.05.  transformed  data  compared  F t e s t . In comparisons of w i t h i n  and body length were  more  variable  the d i f f e r e n c e s were not s t a t i s t i c a l l y In  v a r i a b l e than NR w i t h i n  o f v a r i a t i o n and  a l l other  clones.  characters  Intraclonal  P2 was more  variation  in  P2  d i f f e r s s i g n i f i c a n t l y from NR i n t o t a l j u v e n i l e s , eggs/brood and %  mortality.  There  broods/female o r t o t a l In  comparisons  signficantly all  greater  was no s i g n i f i c a n t eggs/female of  d i f f e r e n c e i n number o f  (Table 17).  interclonal  variation  there  v a r i a n c e i n growthrate i n NR than  other c h a r a c t e r s except  was  a  P2. For  number o f broods/female P2 was  sign  66  T a b l e 17:  F t e s t s comparing r e l a t i v e v a r i a n c e s from t r a n s f o r m e d d a t a w i t h i n and among c l o n e s between p o p u l a t i o n s P2 and NR. Degrees o f freedom f o r P2 = 81 and f o r NR = 86. w i t h i n clones  among c l o n e s  l o g body l e n g t h  F(86/81) = 1.32  F(81/86) = 2.53  log  F(86/81) = 1.36  growth r a t e s  F(86/81) •= -9.0  l o g # o f broods  F ( 8 l / 8 6 ) = 1.02  F(81/86) = 1.07  log  t o t a l eggs  F ( 8 i / 8 6 ) = 1.21  F ( 8 i / 8 6 ) = 2.98  log  total  F(81/86) = 1.65  juvenile  *  *  F(81/86) == 4.00  l o g eggs/brood  F ( 8 i / 8 ) = 3. 13  F(81/86) = 21.25  log % mortality  F(81/86) = 2.48  F ( 8 l / 8 6 ) = -5.68  6  * P2 s i g n i f i c a n t l y more v a r i a b l e than NR a t P < .05 ** NR s i g n i f i c a n t l y more v a r i a b l e than P2 a t P < .05  **  * *  *  67  ificantly  more v a r i a b l e t h a n  Based  on  interclonal even  variances,  though  there  population.  that  flexible  plasticity.  is  Conversely  that  w i t h i n c l o n e s and individuals  The  by  Table  18  and  and  order  than  as  contrast  with  greatest result length,  the  variation implies V1,  eggs/brood %  either  variation  total  than do  look  at  NR  was  earlier a  single  phenotypic  the  and  environment  fitnesses  of  a l s o capable  by t h e  large %  the  o f some  variation  adaptation  in  P2  and  between  and  overall  &NOVA  or of  NR  in  NR  The  P4,  and  in  variation  components  of  greatest  populations  PU,  and  within  juveniles, P5  of  that the  d i f f e r e n c e s between P2 total  further  populations  between P2,  are  sources  indicate  f o r a l l c h a r a c t e r s was  eggs,  P2  e x p e r i m e n t s h a v e been  population.  comparisons  among P2, not  no  to explain  within clones  greater  i n the  with  of  adapt t o  differential  among c l o n e s  nested  was  NR  populational buffering exclusively.  variation  a  may  evidenced  particular  variation  P2  deal  than  the  homeostatic  although  i r r e s p e c t i v e of the from  variable  and  greater genetic variation  variances  to  of i n t r a -  corroborate  great  with  i n d i v i d u a l or  in  a  i t is difficult  within  to  environments.  untransformed  partitioned  seem  NR  flexibility  17).  electrophoretic variation  demonstrate  genotypes i n d i f f e r e n t phenotypic  g e n e r a l l y more  homeostasis  would  (Table  v a r i a n c e s and  individually  variation  populational  done  no  results P2  among c l o n e s  of t o t a l was  genotype  l e s s phenotypic by  P2  was  These  suggestion very  comparison  NR  P5  and  and  NR  in  where  clones.  the This  f o r body  number  of  and,although comparisons  indicate statistically  the  %  magnitude o f  of  these  Table  18: Comparison o f v a r i a t i o n w i t h i n and among c l o n e s and between p o p u l a t i o n s (P2 and NR) f o r p r i m a p a r o u s i n s t a r . V a r i a n c e s and % v a r i a t i o n ( i n p a r e n t h e s e s ) a r e l i s t e d . variation within  body  length  clones  variation  among c l o n e s  v a r i a t i o n between pop.  21.77  (11.53%)  8.65  (4.58%)  number  7.751  (68.95%)  1.4215  (12.64%)  2.07  (18.41%)  variable 1  .0047  (11.59%)  .00171  (4.27%)  .0338  (84.14%)  variable 2  .0038  (66.70%)  .00139  (24.22%)  .00052  (9.08%)  variable 3  .0009  (86.05%)  .00139  (13.95%)  -.00002  (0.00%  growth r a t e  94976  (55.07%)  12888.6  (7.47%)  64599  (37.46%)  number o f eggs  3161.6  (23.05%)  462.21  (3.37%)  10093  (73.58%)  // o f g e n e r a t i o n s  6.6852  (55.64%)  .7975  (6.64%)  4.5317  (37.72%)  // o f j u v e n i l e s  2430.6  (21.90%)  339.07  (3.05%)  8329.7  (75.05%)  #  9.6169  (14.30%)  2.9251  (4.35%)  54.70  (81.35%)  .0044  (92.89%)  .00031  (6.46%)  .00003  (0.65%)  egg  eggs/generation  (eggs-juveniles)/eggs  158.41  (83.89%)  (neg.))  00  69  differences, between  they  P2 a n d NR  Comparison  The  two  form  P2  Mean  was  values in  mortality  differed P2  a n d NR  P2  and  populations  maternal  among effects  genetic  P 2 , P 4 , a n d P5.  NR  independent There  for  mean  among  one  Results are  were  significant  except  geographic  environment,  were  significant of  a  i n among  associated to  short  selection  a l l  population  were  or  NR  since  clones.  with  respond time  i n  period  2)  to  absence  interclonal and  differences characters.  of the  female  were  population  physical  the  due  explanation  Mean the  %  As i n  there  ability  changes  coupled  i n t h e l a b o r 3)  most  presumably  The l a t t e r  1)differences  characters  f o r  growthrate  t o the physiology  convincing  be due t o  clones  of t h e presence  values  i n each  and r e l a t e d  may  directional  NR.  from  n u m b e r a n d % m o r t a l i t y i n NR.  differences  over  between  o f P2 a n d  polymorphic.  significantly  egg  differences  morphological  differences  d i f f e r e n c e s among c l o n e s .  electrophoretic  environment  and  characters  clones  particularly  strong  among  differences  electrophoretically  o f P 2 , P 4 , a n d P5 t h e r e  Differences  to  are real  19.  f o r a l l mean i n  comparisons  is  differed  electrophoretic variation.  differences  or  similarities  monomorphic  i n Table  characters  between  there  the r a t i o n a l e f o r the comparison  populations  summarized  to  and r e a l  that  e l e c t r o p h o r e t i c and e n v i r o n m e n t a l  another;  of  suggest  O f £ 2 A n d NRj. Summary  populations The  do  with  potential  i n  and of the  a lack of genetic  Table  19: A summary o f the g e n e t i c d a t a from P2 and NR.  P2 electrophoretically |  NR homogeneous monomorphic  s i g . d i f f e r e n c e i n mean v a l u e s o f a l l c h a r a c t e r s among c l o n e s  e l e c t r o p h o r e t i c a l l y polymorphic | heterogeneous s i g . d i f f e r e n c e i n mean v a l u e s o f a l l c h a r a c t e r s among c l o n e s  s i g . d i f f e r e n c e s i n mean v a l u e s f o r a l l c h a r a c t e r s between P2 and NR greater % v a r i a t i o n w i t h i n greater % v a r i a t i o n within c l o n e s than among c l o n e s c l o n e s than among c l o n e s  P P2 g r e a t e r o r s i m i l a r v a r i a n c e i f o r a l l c h a r a c t e r s except growth r a t e greater % v a r i a t i o n within c l o n e s i n NR than i n P2 greatest % v a r i a t i o n i s either w i t h i n c l o n e s o r between pop.  71  differences,  electrophoretic  Components population clones  indicate  i n both  inter-  of  and  variation  than  length  indicates than  interclonal and  body  variance  (V1)  the  however  total  amounts  within  clones.  of  NR t h a n based  i s accounted  among P2, P4, and on  the  genotypic  may r e l y  than  variation  This  except  variance,  for  more  the  and data  characters variation  populations  much  w i t h i n and  are  i n P2, P4, and P5, greater  %  populations  supports  the  data,  variation.  strategies  of  the  o f P2 and  hypothesis,  P2 and NR and s u g g e s t s adaptive  among  i n NR i s c o n s i s t e n t l y  and e n v i r o n m e n t a l  on d i f f e r e n t  and p h e n o t y p i c  intraclonal  transformed  of variation  f o r between  electrophoretic  clones  d i f f e r e n t l y w i t h i n a n d among  that a  P5.  P4, and P5 a r e more s i m i l a r populations  among  from  components o f v a r i a t i o n  between P2 and NR i n d i c a t e variatnce  than  and a b s o l u t e  suggests  variance  absolute  a l l characters are  interclonal  populations  i n P2 w h e r e a s t h e g r e a t e r  total  of  among  and f o r egg number/brood. A  of the % variation  There are s i m i l a r  Comparisons  NR  for a l l characters  variance,  clones  and  within  clones  variation  between  population  partitioning clones.  w i t h i n c l o n e s than  P2 was r e l a t i v e l y more v a r i a b l e  each  1-way ANOVA i n e a c h  indicate  within  size  total  NR. A c o m p a r i s o n  within  variances  a  populations.  P2 t h e r e was s i g n i f i c a n t l y g r e a t e r  of the  intraclonal  among  on  % variation  more v a r i a b l e  Within  comparison  greater  based  P2 and NR. A c o m p a r i s o n  (P<.05).  body  variation  intraclonal  significantly  or otherwise,  t h a t P2, the  two  balancing  72  Comparison  Of  P2  Although been  survive  out  have  and  experiments  describe  compared  to  these  in  NH.  NB  on  variation  further from  15  C  reared  were  Morphological  by  PCA  Since  temperature  one  Daphnia  temperature  ability  the  to  of  hand  of environments. buffered of  of t e n c l o n e s from and  and  fecundity and  the  of P2  20  and C  poikilothermic,  It  would  has  important  at  NR  NR  hatched  first  How  eight  to at  vials.  reproduction  morphological  egg  have  been  any an  change effect  repeatedly  production rates  on  characters  temperature the  related  the  flexibility  to  were  population  used at  to each  ability  compare  rate  demonstrated  i n these  changes  variance  in  environmental parameter  the  each  less  and  i n separate  in  within  or  polymorphic.  P2  variation  of  little  variation  similar  expect  Analyses  with  environments?  plasticity  15,  Previous  phenotypic  shows  different  10,  organism  20).  are  and  to  i s electrophoretically  the  have  a l l references  amounts  to  here  environment,  range  other  environment  i s an  described  individually  recorded  {Table  growth,  might  clones  and  at  reactions.  feeding,  a  the  each  and  external  enzyme  in  large  characters  measured  the  the  evaluate  siblings  in  to  as  and  ten  pooled  P2  Experiment  previously  single  p o p u l a t i o n s respond  To  were  a  reproduce  variation  do  Temperature  referred  genetic  phenotypic  NRi  a l l experiments  carried  plasticity  And  that  influencing organisms  and  respond  to  to of  of  the  organism.  differences  temperature  among  treatment.  Table  20: Means and variances f o r morphological reared at three temperatures.  and reproductive characters from P2 and NR  10 C mean  * Means and  15 C variance  mean  20 C mean  variance  variance  body length *  33  1.857  11.00  50  1.519  10.47  35  1.543  9.78  l o g length  33  3.268  .04105  50  3.180  .00084  35  3.187  .00078  egg number  33  7.212  5.9849  50  3.080  1.7077  35  4.086  3.080  l o g egg number  33  .8233  .041047  50  .4611  .03456  35  .5753  .0360  variable 1  33  .00021  .00261  50  -1.454  .00139  35  -.1456  .00141  variable 2  33  .09574  .00346  50  -.00025  .00179  35  -.01576  .00158  variable 3  33  -.01522  .000635  50  .01107  .00051  35  .00197  .00060  body length *  35  2.192  25.11  47  2.241  22.03  45  2.180  27.16  l o g body length  35  3.340  .000939  47  3.349  .00087  45  3.305  .00095  egg number  35  7.429  9.19302  47  6.787  4.736  45  5.511  3.028  l o g egg number  35  .8313  .03884  47  .8074  .02304  45  .7106  .0346  variable 1  35  .08553  .00388  47  .1115  .00278  45  .09170  .00319  variable 2  35  .00720  .00241  47  -.0171  .00186  45  -.04540  .00162  variable 3  35  -.01558  .00105  47  .01047  .00178  45  -.001487  .00294  3 v a r i a n c e s a s s o c i a t e d with body length w i t h i n and among clones and among populations are x 10 ; Co  74  Unlike  the  difference  previous  among c l o n e s  interclonal PCa  no  significant  and  at  3.  10  egg  P2  may  be  NR.  at  among  were  accounted  C.  results  for  the  with  three  However  except  smaller  the  eggs.  different  mean  significant  length,  of  clones  these by  no  15  i n number  NR  significant  was  and  significantly  of  no  i n body  10  another  was  There  animals  number  one  contrast  and  there  There in  at  P2 was  clones  variables  those  2  mentioned  sample  sizes  in  experiment.  within  each  the  number  of  the  and  variables 2  P2  (Table  and  NR  environmental P2  However,  length  temperatures  and  and  or  also  three  and  3  data  to  compare  temperatures.  reproductive  u n l i k e P2  mean  body  differences  P2  replicates  significantly  were s i g n i f i c a n t l y there  were  size  (V1)  from  one  characters.  Egg  different  the  no  in  differences in  in  NR  across  20).  showed  extremely  differences.,These NR  used  differed  for a l l morphological  body  other  at  were  temperatures  replicates.  mean  variance  population  three  another  NR  in  from  which  Analyses  at  P2  difference  C  The  previously this  in  did differ  reared  in  variation  v a r i a b l e s , and  clones  experiments,  and  will  be  different  d i f f e r e n c e s are  responses consistent  further discussed  i n the  to with  final  discussion.  Differences  between  P2  and  analyses  of  variance.  determined  by  and  NR  a l s o compared  the  data  were are  individuals  summarized are  to  NR  one  i n Table  significantly  at  each  Means a n d  another 21  temperature  and  at  each  Figures  l a r g e r than  P2  were  variances  for  temperature 10  and  individuals  also  11.  P2 and NR  at a l l  75  temperatures. However, a comparison length variable.  indicates  neither  of  population  variances is  of  the l o g  significantly  more  Table 21: Comparison o f means and variances i n P2 and NR a t three temperatures.  MEANS  MEANS  VARIANCES  VARIANCES  F(34/32) = 2.28 *  body length  20 C  15 C  10 C  MEANS  VARIANCES  F(46/49) = 2.11  *  F(44/34) = 2.78*  l o g body length  ns  F(34/32) = 1.49  ns  F(46/49) = 1.03  ns  F(44/34) - 1.22  egg number  ns  F(34/32) =1.54  *  F(46/49) = 2.77 *  ns  F(34/44) = 1.02  l o g egg number  F(32/34) = 1.06  F(49/46) = 1.50  F(34/44) = 1.04  variable 1  ns  F(34/32) = 1.49  F(46/49) = 2.00  *  F(44/34) = 2.26*  variable 2  *  F(32/34) = 1.44  F(46/49) =1.03  *  F(44/34) = 1.03  F(34/32) = 1.65  F(46/49) = 3.46 *  ns  F(44/34) = 4.91*  variable 3  * P < .05 ns not s i g n i f i c a n t  of P2 of NR  10  TEMP 15  20  32 34  49 46  34 44  77  F i g u r e 10: P2 (°  Means and 95% ) a n d NR (» )  confidence l i m i t s Daphnia reared at  f o r body l e n g t h in three temperatures.  I  Body Length bo  (mm)  ro 'o  No 139  •a  I — H  O N3  O  Co  79  Figure P2  11: Means a n d 9 5 % c o n f i d e n c e l i m i t s f o r e g g number i n (°) and NS <• ) Daphnia r e a r e d a t t h r e e t e m p e r a t u r e s .  80  1  81  IMhh DISCUSSION  Because reproduce  of  their  reproductive  Daphnia  to  evaluate  v a r i a t i o n on  the  and  phenotypic  variation  It  relative  is  to  important  to  adaptation  interpret  and  parthenogenetic animals g e n e r a l l y and of Daphnia Because assortment  of  the  lack  variable  organisms. observed  a  colonizing  the  genotypes.  Only  the and  different  one  this  fitness  of  specifically. and  independent  might expect Daphnia  than  sexually  that  ponds  each  (one?)  environment a  and  new  be  were  the  capable  exclusion effect,  of  I  species i n  explained  p o p u l a t i o n was  founder  by  the  s t a r t e d by a of  rapidly  all  however,  other would  c o n s i s t e n t l a c k of v a r i a t i o n i n a l l  electrophoretic within  may  which to  profound  complete the  homogeneity  to  reproducing  t o t a l l a c k o f v a r i a t i o n i n t h r e e Daphnia  small number of females  ponds  in  Using e l e c t r o p h o r e s i s to measure enzyme v a r i a t i o n ,  principle:  explain  recombination  genotypically  20 ponds. T h i s extreme founder  of  i n a m e i o t i c parthenogens,  less  and  i n f l u e n c e o f g e n e t i c and environmental  phenotype.  information  be  which  by a c y c l i c a l parthenogenesis, are u s e f u l organisms i n  which to q u a n t i f y genotypic which  biology,  each  similarity  of  animals  from  s p e c i e s . T h i s e x p l a n a t i o n , thus,  seems u n l i k e l y . I f i t i s assumed that enzymes are s e l e c t i v e l y important closely  linked  to  selectively  important  e l e c t r o p h o r e t i c v a r i a t i o n i n Box 22 and NR as  characters, well  as  in  or the the  82  lower and  mainland  spatial  mainland  p o p u l a t i o n s may  stability  shown  environmental  slightly  i n size,  (during  the  seems  depth,  course  of  unlikely  this  physical  NR,  which  t h e lower  (polymorphic  is  must r e m a i n  considered  later  Population reproduction,  little  the  and  do  differ  stability  (P5)  one  dried  another.  homogeneity  spatial  up  Thus,  within a  homogeneity  geographically  electrophoretic  may  be due  of  different  differences  t o both temporal  without f u r t h e r  in physical  in this  data  characteristics  and  concerning of t h i s  pond  rate  of  i n NR  and  information  change  i n genotype  or  P8 which  no  sexual reproduction  specifically  r e c r u i t m e n t from also  lower  Daphnia  frequency  will  explain differences mainland  due  of  be  sexual  other populations, i n the  amount  was  no  evidence  t o m u t a t i o n o r i m m i g r a t i o n i n P2, sampled  and  ponds a l t h o u g h a g a i n t h e r e  on t h e s e p a r a m e t e r s . T h e r e  were p e r i o d i c a l l y  that  on  discussion.  parameters,  unlikely  pond  of environmental s t a b i l i t y  of  is  similar  ponds.  ponds,  t h e r a t e o f m u t a t i o n may of v a r i a t i o n  to  temporal  one  precise  they  lower  speculation.  Other e f f e c t s  it  the  heterogeneity.,However,  this  is  t o any  v s . monomorphic)  temporal v a r i a t i o n  and  temporal  The  exposed  ,although  study  physically  mainland  the  and  electrophoretic  characters within  In  similar  o f t h e o t h e r s ) from  that  with the  environment.  vegetation,  s p e c i e s c a n be a t t r i b u t e d  spatial  the  conditions  c o n s i d e r a b l y i n advance  from  by  ponds a r e g e o g r a p h i c a l l y  external  it  be a s s o c i a t e d  for four  i n t h e s e ponds d u r i n g  months. T h e r e  this  time  r e c o m b i n a t i o n o f gametes f r o m  P4, was  although  genetically  83  i d e n t i c a l i n d i v i d u a l s with few  heterozygotes  would  result  in  genetic changes i n the o f f s p r i n g . The  variation  observed  However,  whether  this  important  is  unknown  phenotypic  differences  clones  suggest  electrophoretically  genetic  variation  (lewontin, among  by  electrophoresis.  importance  of  electrophoretic  demonstrate  1974).  possibly  undetected  the  is  ecologically  The  significant  electrophoretically  differences,  l i n k the function of  i s genetic.  genetic,  Ideally, variability  enzyme  to  identical  to  which  evaluate  correlate  identifiable  i t i s necessary t o  t h e environment  enzyme  possible  data  Clearly,  on  detailed  different  and  types  with  alternatively the  to  phenotypic studies  environments,  these  individual  different  ftyena study.  responsiveness  p o p u l a t i o n dynamics, and  f l u c t u a t i o n s need t o be coupled maintaining  in  v a r i a t i o n as done i n t h i s  of  to  environment,  r e g a r d l e s s o f the s p e c i f i c f u n c t i o n o f t h e enzyme, a s with  the  s e l e c t i o n a c t i n g at the enzyme l e v e l . Since t h i s i s  i m p r a c t i c a l i n most s t u d i e s , i t i s  or  are  to  environmental  t o determine the mechanisms f o r genetic  structures  i n different  populations. In populations of Daphnia t h e r e a r e d i f f e r e n c e s i n means o f morphological regardless  and  physiological  traits  among  populations  o f the e l e c t r o p h o r e t i c or g e o g r a p h i c a l s i m i l a r i t y o f  the p o p u l a t i o n s . Likewise t h e r e a r e d i f f e r e n c e s i n means of some c h a r a c t e r s among c l o n e s w i t h i n populations, again independent of electrophoretic obvious  and  explanation  environmental f o r these  similarity.  There  is  no  mean d i f f e r e n c e s i n such s i m i l a r  84  populations  or  clones.  electrophoretic indication  similarity  of phenotypic  influenced  by  undetected how  by  the  selection  the  different  environment  on  of  respond  which t h e  to p a r t i c u l a r  however  to  relatively  of  one  related  associated  independently  (NR)  than  extremely short  of  i n the  physiological conformity  phenotypes  by  genetic  differences  information  little  not  with  were one  information  of  plasticity although  character  and  in  egg  (P2, P4,  and imply  capable  of  environment.  varying were among  associated  plastic  or was  no  number showed and  t h a t egg  with  obvious and  greater  among  clones  number i s an  responding Egg  the  varying  morphological  P5)  in  difficult  however, t h a t  there  the  specific  characters  those  in  by i t s  coefficients  evidence,  less  that  modified  i n Daphnia are  Similarly  c h a r a c t e r s . T h i s may  suggests  influences. I t i s  or  among  plasticity, be  character  no  on  i n d e g r e e and  that  body s i z e and  more  time to changes i n t h e  both  correlation  another..  amount  f o r other  Morphological  T h e r e was  be  organisms.  characters  on  characters,  plastic  provide  genotype can  each  among p o p u l a t i o n s other  no  may  p h e n o t y p e s , mean d i f f e r e n c e s  environmental  based  characters  difference  Mean  argues  another.  (Table 22).  avoidance  for  whether  characters  predator  a good  differently  individual  relation  assess  and  (1965)  environment, i s s p e c i f i c  independently  n e c e s s a r i l y provide  mean d i f f e r e n c e s among c l o n e s and  f o r some c h a r a c t e r s characters  by  these  s t r a t e g i e s of t h e s e  r a t e o f c h a n g e . Bradshaw amount  that  or  between p o p u l a t i o n s  existence  populations  does not  suggest  similarity.  operates  adaptive  The  differences  e l e c t r o p h o r e s i s ; however, w i t h  among c l o n e s and on  These  number  in a  very  i s  most  Table 22: Comparisons of morphological characters in'P2 and NR.  c o r r e l a t i o n matrix  N=I69  body length  1.000  body width  .986  1.000  t a i l spine  .873  .876  1.000  eye diameter  .343  .333  . 193  1.000  head width  .976  .973  .873  .287  Comparisons of morphological characters i n P2,P4,andP5. c o r r e l a t i o n matrix  N=391  body length  1.000  body width  .908  1.000  t a i l spine  .061  .057  1.000  eye diameter  .320  .239  -.009  1.000  head width  .914  .858  .084  .287  86  likely  correlated  physiology at  with  body  of the parent.  least qualitatively  length  and  with  from t h e  change.  components o f v a r i a t i o n  s u g g e s t d i f f e r e n c e s b e t w e e n P2 genetic  and  23£]lQ.i§ E S l e x and  more  phenotypic  • 2  and  relative  NR  v a r i a n c e s among  w i t h i n and  and  in  among  polymorphic between  and  NR  showed  populations,  variation  Daphnia  less  with the greatest % v a r i a t i o n S i m i l a r data A.  fatua  1965)  have  and  clones, i n NR  been  ( M a r s h a l l and  than  population.  among  clones  electrophoretically  and  variation  among c l o n e s  Lewontin  1970)  in  and  polymorphism (1957)  homeostasis,  where  Avena b a r b a t a  i n Drosophila  flexible,  individual  is  phenotypically flexibility  f i t  by in  a  and  NR  may  1)  composition  by  that be  individual of  the  of t h e  environments of  population where  each  by  being  indiviudal  maximizes f i t n e s s .  similarly  may  populational  homeostasis  of  and  that populations  some c o m b i n a t i o n  genetic diversity P2  either  number by  P2  (Carson,  adaptability  out  individual  p l a s t i c , o r 3)  and  differences in  2)  to  points  the genotypic  than  within clones.  adapt t o change i n the e n v i r o n m e n t  be  animals  phenotypic  described  Allard,  genetic  of  NR  i n t e r p r e t e d r e l a t i v e to the c o n t r i b u t i o n of  h o m e o s t a s i s and  may  were  absolute  within  correlation  less electrophoretic variability  phenotypic  populations.  clones  populations  p a r t i t i o n e d t h e t o t a l v a r i a n c e e q u a l l y w i t h i n and and  among  a negative  variability  Daphn i a w i t h  p  differ  other c h a r a c t e r s examined i n i t s  Comparisons of e l e c t r o p h o r e t i c v a r i a b i l i t y ,  of  general  I n t h i s r e s p e c t i t d o e s seem t o  response to environmental  p o p u l a t i o n s , and  the  These  interpreted  as  87  different  adaptive  strategies  though  they  differ  i n degree  r a t h e r than kind. Whether these d i f f e r e n c e s are q u a n t i t a t i v e  or  qualitative  and  undetermined  and i t seems more p r a c t i c a l to look at P2 and Ne as  populations  which  seasonal  whether they are p a t h o l o g i c a l o r s t r a t e g i c are  change  need and,  to  deal  within  with  different  amounts  any i n d i v i d u a l l i f e t i m e ,  amounts of environmental change. T h i s w i l l be done by  similar  1) f u r t h e r  e s t i m a t i n g environmental s t a b i l i t y of P2 and NR from f i e l d 2) measuring the  f i t n e s s i n p o p u l a t i o n s o f Daphnia £ulex  l a b at t h r e e d i f f e r e n t temperatures, and 3) by  genetic and phenotypic v a r i a b i l i t y stability  i n a model  further  and  interpretation  P2,  shallow  phenotypic  continuing data  in  the  discussion  Dafikfiia  i s primarily speculative,  P4,  and  P5 environment  and  thus  may  be  based  may  .  i s a l a r g e r e s e r v e of ground  b u f f e r these ponds a g a i n s t any  are  short  the  However,  the  on  field  3. not be s t a b l e  a l l small to well  water which may  severe  of  only  or may  sensitive  environmental change. However, the ponds there  and  NR  over s h o r t p e r i o d s o f time. The t h r e e ponds are fairly  in  interpreting  selection  o b s e r v a t i o n s and the data d e s c r i b e d i n T a b l e s 2 and The  reared  i n t e r p r e t a t i o n of environmental s t a b i l i t y of P2  and NR i s necessary b e f o r e genetic  to  data,  environment.  Environmental S t a b i l i t y Of P2 And  A  relative  of  term  any  and  external  shaded  and  sufficiently changes  volume. Long term s e a s o n a l changes i n the lower maniland  in  are not  88  p a r t i c u l a r ! y dramatic phenotypic  and p o p u l a t i o n s may  plasticity  alone.  be a b l e t o s u r v i v e  Populations  of  Daphnia  P e t e r s o n p o n d s , however, a r e t e m p o r a r y ,  d y i n g out  either  of the  up  due  t o the a c t u a l  disappearance  o r by some o t h e r e n v i r o n m e n t a l  temperature density Daphnia  o r amounts  as  a  of  i n t h e s e ponds  changes  associated  of  seem  with  or  if  t h e r e i s no  an  individual  by  the  NR of  because  t h a n by  i n c r e a s e s i t s f i t n e s s by  depth  much  less  at depths  (Toppings,  are located  at depths  experience of  throughout  ouch  time. the  It  in  the  two  in  g r e a t e r than 1969;  30  environmental not  known though  adaptive i n surviving  in  the  I t seems l o g i c a l  that  structure  l o n g term  i n a pond,  then  1971). cm  season.  at s h a l l o w  then they  depths  do  over  a short  Daphnia  survive  itself  environmental  pulex  probably  i t seems u n l i k e l y  the  Creek  minimum/maximum  I f the Daphnia  whether  in  Comparisons  lakes i n Riske  variability  of  eggs  changes o c c u r r i n g  than  However, s i n c e t h e pond genetic  term  ponds by  changes  daily  30 cm  Jansonn,  greater than  is  of these  o f t h i s pond.  similar  variation  w i n t e r i n NR  pond f r e e z e s o v e r . changes  from  long  i n the n e x t  of the l a r g e  profiles  pond.  producing e p h i p p i a l  of progeny  and  population  these  genetic  s h o r t term  (surface)  period  to  a r e p r o b a b l y v e r y few  temperatures  not  respond  dry  decreased  s m a l l e r volume o f t h e  of c o n t i n u e d s u r v i v a l  size  fall  ponds a s t h e y  increased  phenotypic f l e x i b i l i t y .  possibility  temperature  indicate  an  disappearance  which w i l l i n c r e a s e p r o b a b i l i t y  There  the  to  forming e p h i p p i a l eggs r a t h e r population  or  i n the  the  s t i m u l u s , presumably  food,  consequence  in  by  is  since  permanent,  p o p u l a t i o n may changes.  the  be  89  These suggest to  differences  differences  different  been  response  different  i n the a b i l i t y  environments.  described  their  i n g e n o t y p i c and  to  associated  responsible  for  genetically  the  convergence  either  at P2  from  in  In  canalization  actually  NR  was  may  be  among  electrophoretically flexibility  have been  responsible  temperatures.  in  P2  c o n f e r an a d a p t i v e a d v a n t a g e o f mean  adaptive  mean number o f s u r v i v o r s and  a l l temperatures  to  Phenotypic  means  phenotypic may  and  extremely  i n P2  t o determine i f the d i v e r g e n c e  i n NR  adapt  however, b o t h  genotype  however,  p o p u l a t i o n . In comparisons  determined  show  plasticity.  differences  o f means a t d i f f e r e n t  i s difficult  NR  temperatures,  replicates.  i n d i v i d u a l s i n NR,  f o r convergence  and  single  observed  extreme d e v e l o p m e n t a l  It  a  may  i n t h e s e p o p u l a t i o n s has  phenotypic  with  identical  polymorphic by  the  P2  different  be e x p l a i n e d by  flexibility  to  to the environmental s t a b i l i t y  temperature.  responses  r e s p o n s e s may  of these organisms  Adaptability  relative to  phenotypic v a r i a t i o n  g r e a t e r t h a n P2  values  and to (H)  mean number o f e g g s f o r both  however has t h e g r e a t e r v a r i a n c e i n f i t n e s s  than  characters. NR  (Table  23) .  Greater  mean  fitness  fitness  generally  variance  in  Drosophila  pseudoobscura  population  where homozygotes showed  greater  variance  indicate  which  Drosophila  is  in  has  population more f i t ;  similarly  (Lewontin,  fitness of  associated been  1957) less  with  a  low  observed  in  from  average  a  single  fitness  and  than h e t e r o z y g o t e s . T h i s does not Daphnia  or  which  genotype  however, i t d o e s i n d i c a t e two  of  types of  90  Table 23: Means and v a r i a n c e s f o r f i t n e s s based on number o f s u r v i v o r s and number o f eggs from P2 and NR i n the temperature experiment.  NUMBER OF SURVIVORS 10C  15C  20C  W  "  NR  35  47  44  42.0  78.0  P2  33  51  35  39.7  194.7  10C  15C  20C  W  NR  240  301  242  261  P2  232  149  153  178  UJ  TOTAL EGGS  Q u a l i t a t i v e comparison o f mean f i t n e s s MEAN FITNESS HIGHER  LOWER  P2  LOWER  HIGHER  2402 4382  and v a r i a n c e i n f i t n e s s  VARIATION IN FITNESS  NR  .  i n P.2 and NR  91  fitness,  one  associated  with  larger  means  and  v a r i a n c e s , t h e other with s m a l l e r means and l a r g e r Since  there  is  little  environmental  h y p o t h e t i c a l model r e l a t i n g phenotypic and to  s e l e c t i o n and t o the temporal s t a b i l i t y  described.  variances.,  data  available  genotypic  closely  associated  the  environment  advantageous,  variation  of the environment i s  d e s c r i b e d p r e v i o u s l y i n P2 and  phenotype,  i s such  a l l  either  NR  may  that  a  individuals  by  single  phenotype  regardless  of  w i l l tend to converge on phenotypic  flexibility  the  phenotype.  is their  that  optimal  a s s o c i a t e d with  developmental c a n a l i z a t i o n or by s e l e c t i o n f o r genotypes that  be  with s e l e c t i v e pressures on the organism. I f  e l e c t r o p h o r e t i c genotype  for  a  The apparent t r a d e - o f f of i n d i v i d u a l homeostasis and  g e n e t i c polymorphism  NR  smaller  coding  T h i s convergence would account f o r the f o r  reduced v a r i a n c e among c l o n e s and i n the p o p u l a t i o n . I n t h i s  model any  intraclonal  attributed  to  variation  experimental  then  this  in  this  study  is  e r r o r . I f i n P2 the environment i s  l e s s r e s t r i c t i v e and t h e r e i s phenotype,  observed  little  would  selection  account  v a r i a t i o n i n the p o p u l a t i o n and the  for a  f o r greater  distribution  of  single  absolute variances  w i t h i n and among c l o n e s . The  severity  of  selection  in  these  i n f l u e n c e d by the environmental s t a b i l i t y . , environment  are of  the  same  or  p o p u l a t i o n s may be If  shorter  changes  duration  generation time of the organism a d a p t a t i o n can only by  i n the than the  take  place  i n d i v i d u a l homeostasis. The organism cannot respond t o s h o r t  term environmental changes by g e n e t i c changes  unless  they  are  92  associated  with  the  development o f the o r g a n i s m . I f , however,  changes i n the  environment take l o n g e r than the g e n e r a t i o n  adaptation  t a k e p l a c e by  may  I f the and  NR  might  g e n e t i c changes i n the  measures o f g e n o t y p i c  and  phenotypic  are a r e a l i n d i c a t i o n of the a d a p t i v e assume  P2  is  well  f l u c t u a t i o n s with l i t t l e changes.  NR  may  adapt t o s h o r t diversity  environmental  a l s o be s u f f i c i e n t l y  NR  population  variability  in  homeostasis the  population  reproduction.  necessarily maintain  is  long  individually of  rely  its  Since  on  is  dependent  and  is  on  maintained  parthenogenetic  recombination  This  has  been  Rumina d e c o l l a t a  Avena b a r b a t a phenotypically  which  and  proposed  and  are  for  i n part  random  assortment and  reproduction  and These  parthenogenetic  for  of  i n parthenogenetic  maintained  other  populations  unaffected by  differences  to  the  of  in  by  selection  oats,  report  the l a c k of or  the  and  large sexual  some  other  t h e amount o f v a r i a b i l i t y  mode  of  the  measuring  o r g a n i s m s seem t o s u g g e s t t h a t v a r i a t i o n  as r i g o r o u s l y l i n k e d  to  wild  studies  to  individual  populations  populations  by  cannot  e l e c t r o p h o r e t i c a l l y homogenous  amounts o f v a r i a t i o n a p p a r e n t l y  be  term  genetic  organisms  variability  v a r i a b l e . However, a l l  variability  mechanism.  to  genetic  a l s o buffered over long  genetic d i v e r s i t y phenotypic  environment.  genetic  term  buffered  h o m e o s t a s i s seem t o be a more r e l i a b l e means o f a d a p t i n g  snail,  one  environmental  severe  because  P2  differences.  Populational  sexual  variation in  s t r a t e g i e s then  t o adapt t o  term changes. F u r t h e r ,  the  population..  adapted t o s h o r t term  ability  time  reproduction  in  may  not  as  to  93  selection  and  environmental  £!&bnia phenotypic  are  apparently  flexibility  variability  seem  environmental  stability,  to  Hardy-Weinberg undergo  and  be  more  closely  associated  than  adaptation  suggest  frequent  to  both  reproductive data  from  genetic  sexual  in  Daphnia  overwintering  ephippial  consequences  of  sexual  formation  of  ephippial  difficult  times  i n these  is  eggs.  ponds.  is  an  their  provides  of  i n these a  means  Hebert  permanent to  presumably alternative  and  ability  Regardless  with  closer  ponds, w h i c h  flexibility  reproduction eqqs  t e m p o r a r y and  variation  of  phenotypic  strategy.  reproduction.  phenotypic  polymorphism  amounts  genetic  e q u i l i b r i u m i n temporary  more  large  both  (1974) d o e s , however, p r e s e n t s that  of  and  parameters  populations  capable  to the  genetic produce qenetic  individuals of  the  surviving  94  LITERATURE  Bacci, G., G. C o g n e t t i , A . C . d e t e r m i n a t i o n i n Daphnia  CITED  V a c c a r i . 1961. E n d o m e i o s i s and s e x p u l e x . E x p e r i e n t i a 15: 5 0 5 , ;  B a n t a , A.M. 1 9 3 9 . Studies on the physiology, genetics, and evolution of some Cladocera. C a r n e g i e I n s t . Wash. P a p e r n o . 3 9 . De p t . G e n e t i c s p u b l . No. ,513. B a n t a , A.M.and T. Wood. 1927. A originating by mutation. V e r e r b u n g s w i s s 1: 3 9 7 - 3 9 8 .  thermal race of Cladocera Verhandl. V. I n t . Congr.  Bradshaw, A.D. 1 9 6 5 . Evolutionary significance of p l a s t i c i t y i n p l a n t s . Adv. G e n e t . 13:115-156. Brooks, J.L. 1957. Memoirs o f Conn.  Systematics of North American A r t s and S c i e n c e s . 13:100-180.  B r o o k s , J . L . And S . I . Dodson. competition of plankton. Carl,  phenotypic  1965. P r e d a t i o n , body Science 15:28-35.  G.C. 1941. The d i s t r i b u t i o n living copepods in British 10:55-100.  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Predator-prey l a c u s t r i n e ecosystem. Ecology  State  University  interaction 53:248-258.  in  a  of  New  tropical  APPENDIX  Buffers:  LiOH Stock A ( e l e c t r o d e b u f f e r ) pH = 8.1 2.4 g LiOH 23.8 g b o r i c a c i d make up to 2 1 w i t h d i s t i l l e d w a t e r Stock B  pH = 8.4 12.4 g TRIS b u f f e r 3.2 g c i t r i c a c i d make up t o 2 1 w i t h d i s t i l l e d  Gel b u f f e r  water  25 ml Stock A + 215 ml S t o c k B  250 v o l t s f o r 3 hours Poulik Electrode buffer  Gel b u f f e r  pH 8.12 37.10 g b o r i c a c i d 4.8 g NaOH make up t o 2 1 w i t h d i s t i l l e d  water  pH = 8.62 18.42 g TRIS b u f f e r 2.10 g c i t r i c a c i d monohydrate make up t o 2.1 w i t h d i s t i l l e d w a t e r  250 v o l t s f o r 3 hours  EDTA G e l and E l e c t r o d e b u f f e r s pH = 9.00 42.2 g TRIS b u f f e r 1.2 g EDTA 2.0 g b o r i c a c i d make up t o 4 1 w i t h d i s t i l l e d add 20 mg NAD to g e l b u f f e r when making g e l 350 v o l t s f o r 4 hours  water  Stains:  Used w i t h L i O H : ES i n c u b a t e i n TRIS. m a l a t e : T r i s malate 100 ml (see LAP s t a i n ) f a s t b l u e RR 20 mg Na napthyl acetate 10 ml (lOOmg i n 5 ml water + 5 ml acetone) GOT TRIS (0.1 M) pH = 8.5 100 ml aspartic acid 4.40 mg ketoglutaric acid 240 mg f a s t b l u e BB 80 mg p y r i d o x a l 5' phosphate 2 mg  Used w i t h P o u l i k : AKP TRIS HC1 (0.1 M) pH = 8.5 PVP 500 mg f a s t b l u e BB 100 mg n a p t h y l a c i d phosphatase MgCl2 60 mg MnCl2 60 mg NaCl 2 g  100 ml  100 mg  AP i n c u b a t e f o r 30 min. i n 0.5 M b o r i c a c i d , then t o : 0.125 M sodium a c e t a t e pH=5.0 100 ml PVP 500 mg N a - n a p t h y l a c i d phosphatase 100 mg f a s t b l u e BB 100 mg LAP i n c u b a t e f o r 30 min. i n 0.5 M b o r i c a c i d , then t o : TRIS malate 100 ml 12.1 g TRIS 11.6 g m a l e i c a c i d 1.0 N NaOH 1 ml make up to 1 1 w i t h d i s t i l l e d w a t e r f a s t b l a c k K 20 mg Na L - l e u c i n e 20 mg  Used w i t h EDTA: MDH TRIS H C l 0.1 M pH='8.5 malic acid 50 mg NAD 20 mg KC1 10 mg PMS 2 mg  ODH TRIS H C l 0.1 M NAD 25 mg NBT 20 mg Octanol 5 ml PMS 2 mg  pH=8.5  100 ml  SDH TRIS HCL 0.1 M pH=8.5 NAD 25 mg NBT 20 mg D-sorbitol 500 ug PMS 2 ug  100 ml  XDH TRIS H C l 0.1 M pH.7-7.4 hypoxanthine 100 mg NAD 25 mg PMS 5 mg NBT 20 mg KCL 100 mg  100 ml  PGI TRIS H C l 0.05 M pH 8.5 100 ml MgCl2 100 mg fructose-6-phosphate 25 mg NADP 15 mg MTT 25 mg G-6-PDH 25 u n i t s PMS 10 mg AO TRIS H C l 0.05 M pH 8.5 benzaldehyde 1 ml NBT 20 mg NAD 25 mg EDTA 10 mg PMS 10 mg  100 ml  

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