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Female giant toads inflate themselves to deal with undesirable males

Giant Cane Toad (Bufo marinus) females are able to reject undesirable males by inflating themselves. By doing so, the females can choose a suitable and fit male. It was Bas Bruning, an animal ecologist at VU University Amsterdam, who discovered this.

In the mating season, many amphibian males have their territory near water. Here they croak to attract females, mount them (in the typical amphibian manner known as amplexus), and thus fertilize the eggs the females lay in the water. However, there are also males that do not croak even though they pounce on every female they see. These ‘satellite males’ remain in place until the female produces eggs whereupon the male fertilizes them.

By inflating herself whenever a fight takes place between various males on her back, she can influence the result so that one particular male eventually wins.