A large population of laboratory animals has been allowed to…

A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 25% of the animals display a recessive trait (aa), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants.   What proportion of the population is probably heterozygous (Aa) for this trait?

You are studying three populations of birds. Population A ha…

You are studying three populations of birds. Population A has 10 birds, of which 1 is brown (a recessive trait) and 9 are red. Population B has 100 birds, of which 10 are brown. Population C has 30 birds, and 3 of them are brown.   Which population is most likely to be subject to the bottleneck effect?