Australasian Science: Australia's authority on science since 1938

Sneaky Males Switch on Their Female Brain

The full text of this article can be purchased from Informit.

Researchers at The University of Otago have observed how males of some species disguise themselves as females in order to improve their chances of mating.

Dr Erica Todd says one of the most extraordinary ways animals have responded to the challenge of mating is female mimicry, where so-called “sneaker males” disguise themselves as females to avoid aggression from larger males and then steal mating opportunities. Todd’s study, published in Molecular Biology and Evolution, found that sneaker males can achieve their extraordinary feat of subterfuge by turning specific genes in their brains and gonads on or off.

Todd says her study species, the bluehead wrasse, has a social organisation that rivals the most outrageous soap opera. “There are two types of males – large, aggressive blue-headed males that openly court females, and smaller ‘sneaker’ males that look and act like females in order to sneak in matings,” she said. RNA sequencing revealed that sneaker males had brain gene expression patterns that were almost identical to females and very different to territorial males.

The study also revealed how sneaker males make themselves look like females to sneak past other males and avoid confrontation. “Males of many species use bright colours and other ornamentation to attract mates and compete with rivals, which are often regulated by male sex hormones...

The full text of this article can be purchased from Informit.