Question

1.Describe how parasites may exert negative frequency dependent selection on their hosts.

2. Discuss how evolution of two focal species is expected to differ under Müllerian mimicry vs. Batesian mimicry.

Answer 1

1. Host parasite coevolution is a type of coevolution. In negative frequency dependent selection, an allelic variant has a selective advantage.

For example, the parasite should adapt to the common host genotype. Then only it'll be able to affect a large number of hosts. Therefore it's frequency will increase and it'll be common. Coevolution by this method is very rapid. It is able to maintain high genetic diversity. This selection is expected mostly for multicellular hosts.

2.Batesian mimicry: Myrmarachne , an ant mimicking spider looks similar to Oecophylla Smaragdina, the weaver ant, which is it's predator. The spider would have been swarmed and eaten by the ants if it would not be similar to the ants. Another example of this mimicry is the monarch butterfly and the viceroy butterfly.

Mullerian mimicry: biological resemblance of unrelated dangerous organisms. For example, Chrysididae, Apidae, Ampulicidae which are cuckoo wasp, type of bee and cockroach wasp respectively, have adapted the same colour. They are all different species having metallic green colour. They are all stinging insects.