Exam 3

• The figure depicts an experiment that was conducted to test the hypothesis that mouse fur color relative to the background would affect their susceptibility to predation.  Mouse models were set out and students observed the number of attacks that occured. In the bar plots, the background color represents the background  color in the environment and bar color represents fur color.  What can you conclude from the results of this experiment?

  Brown mice experienced a greater proportion of attacks on white backgrounds

  
• Based upon the figure below, which statements are well-supported?

  Light colored mice form a monophyletic group

  Light colored mice evolved multiple times

  
• What type of mimicry is exhibited by the king snake given that both the scarlet and mimic king snake are the same sepcies?

  Batesian, the king snake is not venomous
• What is one reason why king snakes don't look more like coral snakes in the south and are not better camouflaged in the north?

  Gene flow
• The size of the galls produced by the gall fly larvae is heritable.  Based on the figure below, what type of selection is acting on the extended phenotype of gall size?

  Stabilizing

  
• In the figure, the star represents an adaptive mutation while the circles represent neutral mutations (not adaptive). Why did the 3rd (left to right, light blue) and last neutral mutation (green) increase in frequency?

  Linkage with the adaptive mutation

  
• Why does the frequency of the lactase allele in humans vary with geography?

  Natural selection, the epicenters of high lactace frequency corellate with areas where cows were domesticated
• What factors contributed to the decline in the size of native Australian black snake heads after the introduction of cane toads by humans?

  The toads are poisonous to the snakes and the larger the toad, the more poison

  snakes with smaller heads consume smaller toads
• What is a regulatory network?

  collection of interacting molecular regulators 
• True or False: Novel traits can arise when existing genes are expressed in a new developmental context

  True
• True or False: Adaptation usually involves the creation of novel RNA and proteins

  False
• When new traits evolve, it's important that the original function of a gene is maintained.  How can this occur?

  Gene duplication

  Promiscuous proteins
• Which evolutionary processes drive the recruitment or "reprogramming" of genes following a duplication event?

  Mutation

  Selection

  Genetic Drift
• In Lenski's experiment in the evolution of bacteria, where 12 replicate colonies were maintained for 25 years through over 50,000 generations, why was there selective pressure for the evolution of citrate metabolism in the presence of oxygen?

  There was a limited amount of calories in the growth medium
• Genes involved in snake venom production were co-opted from

  Brain, Salivary gland, Thymus, Heart, Pancreas, Lung, Liver, and Muscle
• The eyes of humans and octopods are both camera-like.  This is an example of:

  Convergent evolution
• The eyes of humans (deuerostomes) and octopods (protostomes) contain the same types of proteins involved in vision.  This is an example of

  Homology
• Which are evolutionary advantages of sex?


  Faster Evolution

  Generation of novel genotypes and haplotypes
• What is the Red Queen effect?

  Increased speed of evolution is beneficial in coevolutionary arms races
• Two species have the same census population size.  One is composed of sea lions where males have harems that limit mating opportunities to a small number of males. The other is composed of seals where there is little variance in the reproductive success of males. In which population is genetic drift stronger?

  Sea lions, variance in reproductive success makes the effective population size smaller
• Which are direct benefits of female choice? (multi)

  1. Protection
  2. Nests
  3. Food
  4. Help raising young
  5. Reduced risk

  all
• In a species of spider, the male allows himself to be consumed by the female during mating.  Why is this directly adaptive for the male?

  The eggs laid by the female have a higher caloric content
• 1. An experiment was performed to test whether parents would modulate the amount of resources they give to their offspring.  Showy orange feathers were clipped off of some chicks but not others. In one treatment, all chicks in the nests had the orange feathers trimmed off, leaving a black appearance.  In the other treatment, half of the chicks in the nests had the orange feathers trimmed.  

  Which of the statements below are true

  The parent devoted less resources to offspring without the orange feathers when there were chicks with showy orange feathers in the same nest

  
• Is it in the mother's best interest to devote as many resources as possible to her present litter?

  No
• Why do human females undergo menopause rather than reproduce throughout their entire adult lives?

  Parental care given to grandchildren increases fitness

  The risk of complications with reproduction at older age selectes for reduced fertility

  The increased chance of mortality at older ages reduces fitness of offspring