Page 13 - Children's Book

I quickly realized that the phenotypic variation between the three friends is
what caused their girlfriends to initially be attracted to them. Phenotypic
variation occurs when there is variability in the appearance of a certain trait
of an organism. I also recognized that this game was being driven by sexual
selection. Sexual selection is a form of natural selection when one sex has
preferences of certain traits on the opposite sex. This was occurring when
each of the 3 lizards’ girlfriends were selecting their mates based on throat
color.