During mating, who is the choosy one? It depends on the temperature you are reared.

Well, at least it is true in a particular species of butterfly, Bicyclus anynana, which exhibits sexual dimorphism.

Sexual dimorphism is the condition whereby the sexes of the same species differ in their physiology, morphology or behaviour, that is beyond the differences in their sexual organs.

NUS Associate Professor of Science Antonia Monteiro's research on Bicyclus anynana shows that this species of butterfly exhibits a sex-role reversal in choosiness, courtship behaviour, brightness of ornamentation and size. In addition, all these traits are controlled by developmental rearing temperature. To learn more, click here.

An image of Bicyclus anynana butterflies mating, the larger one is female.

P.S.: Sexual dimorphism can be observed in humans as well, click here to find out.