FRQ’s  for  Evolution:      ANSWER  KEY             please  return    

#1  (2014)      Adult  male  guppies  (Poecilia  reticulata)  exhibit  genetically  determined  spots,  while  juvenile  and  adult  female  guppies  lack  spots.  In  a  study  of  selection,  male  and  female  guppies  from  genetically  diverse  populations  were  collected  from  different  mountain  streams  and  placed  together  in  an  isolated  environment  containing  no  predators.    The  study  population  was  maintained  for  several  generations  in  the  isolated  area  before  being  separated  into  two  groups.  One  group  was  moved  to  an  artificial  pond  containing  a  fish  predator,  while  a  second  group  was  moved  to  an  artificial  pond  containing  no  predators.  The  two  groups  went  through  several  generations  in  their  new  environments.  At  different  times  during  the  experiment,  the  mean  number  of  spots  per  adult  male  guppy  was  determined  as  shown  in  the  figure  below.  Vertical  bars  in  the  figure  represent  two  standard  errors  of  the  mean  (SEM).      

       #2    (2015  #3)  The  amino  acid  sequence  of  cytochrome  c  was  determined  for  five  different  species  of  vertebrates.  The  table  below  shows  the  number  of  differences  in  the  sequences  between  each  pair  of  species.      

 

   #3    (2004)  Darwin  is  considered  the  “father  of  evolutionary  biology”.    Four  of  his  contributions  to  the  field  of  evolutionary  biology  are  listed  below.      

o The  nonconstancy  of  species  o Branching  evolution,  which  implies  the  common  descent  of  all  species  o Occurrence  of  gradual  changes  in  species  o Natural  selection  as  the  mechanism  of  evolution  

 

a.    For  EACH  of  the  four  contributions  listed  above,  discuss  one  example  of  supporting  evidence.  

b.    Darwin’s  ideas  have  been  enhanced  and  modified  as  new  knowledge  and  technologies  have  become  available.    Discuss  how  TWO  of  the  following  have  modified    biologists’  interpretation  of  Darwin’s  original  contributions.     Hardy  Weinberg  equilibrium     Punctuated  equilibrium     Genetic  engineering      

 ANSWER:  A)  max  8  pts,  2  pts  each  Contributions Possible examples of evidence-1pt Explanation/understanding of phrase-1pt The nonconstancy *Must demonstrate variation *Individual variation within a species/ of species ex. Finches, horses, dogs, whales, etc population (can be phenotypic or genotypic) *Change within species over time (not change in an individual) *Change in number of species over time Branching evol. *Must demonstrate common ancestry *Shared or common ancestor which implies the ex. Homology(embryological, structural, *Adaptive radiation concept (divergent common descent molecular processes) evolution, one species becomes 2/more) of all species ex. Vestigial structures from common ancestor ex. Hominoids, finches, etc Occurrence of *Must demonstrate change over time *Small changes over time/slow rate of gradual changes (generations) change/incremental in species ex. Vestigial structures (pelvic bones, *Genes mutate -->selection occurs --> appendix) population evolves ex. Fossil sequence *Accumulation of genetic/phenotypic ex. Coat color changes changes ex. Giraffes neck ex. Antibiotic/pesticide resistance natural selection *must demonstrate an appropriate *Differential reproductive success as the mechanism natural selection effect *Survivors pass genes to next gen for evolution ex. Antibiotics/pesticide resistance *No Lamarckian language (want, need..) ex. Finches, moths, etc *No "survival of the fittest" alone ex. Predator/prey relationships NOTE:  Examples  in  context  may  earn  2  pts     Possible  examples  are  not  limited  to  listings  above.     An  example  alone,  without  the  context  of  the  phrase  =  no  points.  B)  max  6  pts-­‐  3  pts  each   Definition/Explanation of the Desctiption of how it has Depth of discussion/ Idea- 1 pt enhanced/modified expansion point- 1 pt interpretation of evol- 1pt *discuss evidence *deeper description of the theory *Direct mention of Darwin's *describe applicable view is not necessary for pts technology Hardy- *Allele (gene) frequency *D-Ongoing gradual change Examples: Weinberg remains constant over time HW-constant allele ratio *Five conditions of HW cited Equilibrium *Under certain conditions (must refer to alleles or genes) correctly (need all 5) no evolution occurs 1-very large pop size-no drift 2-no movement in/out of pop 3-no net mutations

*HW equation without 4-random mating-no sex sel'n explanation of variables within 5-no natural selection equation = no points HW as a null hypothesis for determining cause of change Punctuated *Sudden changes in tempo *D- Gradual change Examples: Equilibrium *Long period of stasis then PE- possible rapid change *A graph of punctuated sudden change evol vs. Darwinian evol *Discussion of fossil record reflecting a punctuated equilibrium pattern Genetic *Manipulation and/or *D-Natural gene transfer Examples: engineering alteration of genes/DNA GE-human directed gene *Cloning process explained *Others related to transfer *RFLP analysis explained biotechnology *Universality of genetic code *D-gradual change GE-rapid change *DNA analysis allows genomic comparisons    #4    (2001,  similar  to  the  2004  question  above)  Charles  Darwin  proposed  that  evolution  by  natural  selection  was  the  basis  for  the  difference  that  he  saw  in  similar  organisms  as  he  traveled  and  collected  specimens    in  South  America  and  on  the  Galapagos  Islands.    

a.    Explain  the  theory  of  evolution  by  natural  selection  as  presented  by  Darwin.  b.    Each  of  the  following  relates  to  an  aspect  of  evolution  by  natural  selection.    Explain  three  of  the  following.  

i.    Convergent  evolution  and  the  similarities  among  species  (ecological  equivalents)  in  a  particular  biome  (  for  example,  tundra,  taiga,  etc)  ii.    Natural  selection  and  the  formation  of  insecticide  resistant  insects  or  antibiotic  resistant  bacteria.  

  iii.    speciation  and  isolation  iv.    natural  selection  and  behavior  such  as  kinesis,  fixed  action  pattern,  dominance  hierarchy,  etc.  

  v.    natural  selection  and  heterozygote  advantage    #5  (2013  #3)  Fossils  of  lobe-­‐finned  fishes,  which  are  ancestors  of  amphibians,  are  found  in  rocks  that  are  at  least  380  million  years  old.  Fossils  of  the  oldest  amphibian-­‐like  vertebrate  animals  with  true  legs  and  lungs  are  found  in  rocks  that  are  approximately  363  million  years  old.  Three  samples  of  rocks  are  available  that  might  contain  fossils  of  a  transitional  species  between  lobe-­‐finned  fishes  and  amphibians:  one  rock  sample  that  is  350  million  years  old,  one  that  is  370  million  years  old,  and  one  that  is  390  million  years  old.    

 

   #6  (2003)  Biologists  are  interested  in  preserving  the  diversity  of  living  organisms  on  the  planet.  a.    Explain  THREE  of  the    following  processes  or  phenomena,  using  an  appropriate  example  for  each.     -­‐  mutation     -­‐  adaptive  radiation     -­‐  polyploidy     -­‐  population  bottlenecks     -­‐  growth  of  human  populations  b.      For  each  process  or  phenomenon  you  selected  in  a,  discuss  its  impact  on  the  diversity    of  life  on  Earth.        #7    (1994)  Genetic  variation  is  the  raw  material  for  evolution.  

a.    Explain  three  cellular  and  /or  molecular  mechanisms  that  introduce  variation  into  the  gene  pool  of  a  plant  or  animal  population.  

  b.    Explain  the  evolutionary  mechanism  that  can  change  the  composition  of  the  gene  pool.  A) 6 pts max- 2 pts max each category (1 pt general explanation + 1 pt elaboration or explained example) Mutation 1 pt- mutation is a change in the DNA 1 pt- explain mutagenesis 1 + 1- point mutations 1 + 1- substitution 1 + 1- frameshift- insertion/deletion 1 + 1- editing error – repair Chromosomal mechanisms 1 + 1- translocation/transposition 1 + 1- inversion 1 + 1- deletion 1 + 1- duplication 1 + 1- crossing over- new combinations of linked alleles 1 + 1- aneuploidy ( non-disjunction) 1 + 1- polyploidy Other mechanisms 1 + 1- transposable elements 1 + 1- virus induced changes 1 + 1- genetic engineering Sexual reproduction 1 + 1- meiosis as a reshuffling mechanism

1 + 1- recombination of genes (alleles) 1 + 1- independent assortment 1 + 1- random fertilization 1 + 1- cross breeding B) 6 pts max- 2 pts max each category (1 pt general explanation + 1 pt elaboration or explained example) Natural selection explanation- 1 pt- differential reproductive success (survival of the fittest not enough) Elaboration- max 1 pt -adaptation viewed as a “result” -adaptive radiation -importance of variation -occurs in populations not individuals OR example- max 1 pt Gene flow explanation- 1 pt- immigration or emigration of alleles Elaboration- max 1 pt -outbreeding -geographic isolation - barriers- addition/removal geography/temporal/reproductive/behavioral OR example- max 1 pt Genetic drift explanation- 1 pt- non representative, random change in allelic frequency- linked with small population size Elaboration- max 1 pt -bottleneck effect, founder effect -effect of a small population OR example- max 1 pt Mutation explanation- 1 pt- change in genes or alleles in context as an evolutionary mechanism Elaboration- max- 1 pt -randomness -non-directionality -change in phenotypic traits -gametic not somatic change OR example- max 1 pt Assortative mating explanation- 1 pt- non-random choice Elaboration- max- 1pt -sexual selection -artificial selection -in-breeding OR example- max- 1 pt    #8  (  2004)  Prokaryotes  are  found  throughout  the  biosphere.    Answer  two  of  the  following.  

a. Provide  3  examples  of  adaptations  found  in  various  prokaryotes.    Explain  how  these  three  adaptations  have  ensured  the  success  of  prokaryotes.  

b. Discuss  how  prokaryotes  early  in  Earth’s  history  altered  environments  on  Earth.    #9  (1999)  Scientists  recently  proposed  a  reorganization  of  the  phylogenetic  system  of  classification  to  include  the  domain,  a  new  taxonomic  category  higher  (more  inclusive)  than  the  Kingdom  category,  as  shown  in  the  following  diagram.    

 • Describe  three  kinds  of  evidence  that  were  used  to  develop  the  taxonomic  scheme  above,  and  explain  

how  this  evidence  was  used.  The  evidence  may  be  structural,  physiological,  molecular,  and/or  genetic.    • Describe  four  of  the  characteristics  of  the  universal  ancestor.            

#10  (2011 #4) Phylogeny reflects the evolutionary history of organisms. (a) Discuss TWO mechanisms of speciation that lead to the development of separate species from a common ancestor. (2 pts max)

(b) Explain THREE methods that have been used to investigate the phylogeny of organisms. Describe a strength or weakness of each method.

(c) The two phylogenetic trees represent the relationship of whales to six other mammals. All of the organisms shown have a pulley-shaped astragalus bone in the ankle except for the whale.