Animal Gender Roles
July 28, 2017
It is common these days for people to reverse traditional gender roles. In the animal kingdom, however, it is a rare thing for males and females to switch traditional roles. Sex-role reversal in the animal kingdom has been observed only in seahorses and pipefishes, giant water bugs, and jacana and phalarope birds. Recently, however, scientists added another animal to the short gender role reversal list: the smooth guardian frog (Limnonectes palavanensis) of Borneo, a large island in the South China Sea.
In June 2017, scientists reported in the journal Behavioral Ecology and Sociobiology that female smooth guardian frogs have been discovered serenading males in an attempt to win them over—a reversal of most animal mating rituals. These frog females, like so many lovesick Juliets, sing to woo their amphibian Romeos. In response, a male sings out with a call to let the female know if he is available. Then, if the mating is successful, the male sticks around and tends the eggs for 9 to 11 days. After the eggs hatch, the male carries the tadpoles on its back to suitable pools of water where the tadpoles will grow and mature into adult frogs. The study also found that male smooth guardian frogs do not defend their territory and do not have an aggressive call to ward off predators—a task left to the serenading and wooing Juliets of the species.
Most other frogs operate in the opposite manner. Male frogs will enter a pool of water and then call to attract mates. Their call also directs other males to the water, who assume it is a suitable spot for mating. If all goes well, then, the female frogs watch over the eggs and newly hatched tadpoles. Usually, too, male frogs bark to scare off unwanted guests around the lily pad.