Q 9 Alarm calls are common in ground squirrels of several
species. When a squirrel squeals the equivalent of “badger or
snake”, some squirrels scurry into their little holes, hide and
avoid getting eaten by predators (shy a co-dominant character), an
alternative allele causes others to respond by sticking their heads
out of the hole to look for new foraging opportunities (bold
codominant) and the heterozygote chooses randomly. Our focal
population was in Hardy Weinburg equilibrium with exactly 50% of
each shy/bold morph, but a new predator causes bold to have a
mortality (death) rate of 50% before reaching reproductive
maturity. a) What are the allele and genotype frequencies before
selection ? c) What is the fitness of the homozygous ‘shy’ and
‘bold’ phenotypes, what proportion of bold is lost before breeding
? d) How large does the benefit ( in terms of number of brother,
sisters or cousins) of responding to alarm calls by kin and not
dying have to be for kin selection to evolve in the population ?
Use Hamilton’s rule to explain. e) If this very successful predator
multiplied and preyed on 3 large local populations that differed in
allele frequency, what would you predict about the landscape of
fitness and the outcome of longterm selection in these squirrels
?