Male and female beetles fight over penis spines
ANTAGONISM is built into the nature of sexual reproduction itself. Members of each sex try to maximise their own reproductive fitness, which is a combination of the quality and the quantity of offspring they are able to raise to the point where those offspring can themselves reproduce. If conflict between males and females is part and parcel of reproduction, some still have it much tougher than others. Spare a thought, in particular, for the females of the cowpea seed beetle.
Males of this species have penises armed with sharp spikes. These can do serious damage to a female’s reproductive tract. And all in the name of male procreative success, for previous research has shown (though the precise mechanism remains obscure) that male cowpea seed beetles with longer penile spines have greater mating success than those with short ones.
Evolutionary theory predicts that it would be in the interests of females to fight back, by…Continue reading
Source: Economist