Question

Define sexual dimorphism and runaway selection

Answer 1

Sexual Dimorphism: its a phenomenon when two sexes of same species show or exhibit different characteristics beyond their phenotype, size, color, sexual organs, secondary sexual organs. the differences are quite sublte or extremely exaggerated beneficial towards their sexual selection.

For example:

1. Peacock and peahen- show a quite differrences in their phenotyopic appearranace on the basis of their color.
2. During the presence of breeding pulmage, the male mallards shows a bottle green neck distinguishes the sexual selections from other male mallards.

Runaway Selection: This phenomenon is also mentioned or referred as fisherian ruaway was first coined by Dr. Ronald Fisher to account the sexual selection of male sexes on the basis of their exaggerated dimorphism, ornamentation and behavioural selection of female sexes.

if we focus on the traits of peacock having sexual pulmage as its tail, long tailed birds are generally considered as incompatible for natural selection, thou the phenotypic characters of peacock has showed up positive feed back in the subsequent generation and lead to the selection procedures due to specific traits which increased exponentially.