I knew nature was creative and complex, but these two examples took it up a notch
> As a result of changes in the social role, a fish (blue-headed wrasse) can progress rapidly through these phenotypes. Upon the disappearance of a terminal-phase male, the behavior of the largest female in the group converts to male-like behavior in minutes and the fish shows full gonadal changes in days.
> In litter-bearing mammals such as mice, rats, gerbils, and pigs, each pup shares the uterus with several others, some of which are of a different sex. Significant differences among females occur if the fetus is located between two males or with a male on one side or with no male on either side.
I knew nature was creative and complex, but these two examples took it up a notch
> As a result of changes in the social role, a fish (blue-headed wrasse) can progress rapidly through these phenotypes. Upon the disappearance of a terminal-phase male, the behavior of the largest female in the group converts to male-like behavior in minutes and the fish shows full gonadal changes in days.
> In litter-bearing mammals such as mice, rats, gerbils, and pigs, each pup shares the uterus with several others, some of which are of a different sex. Significant differences among females occur if the fetus is located between two males or with a male on one side or with no male on either side.