Female frogs may croak to deter males from mating with them

Male frogs often force females to mate with them, but in one species, a croak from the female seems to persuade males to leave her alone. The sound may be an “honest” signal that she isn’t fertile and mating would be a waste of the male’s sperm and energy.

“In general, male frogs are known to jump on even inorganic objects if they are female-like,” says Makoto M. Itoh at Nagoya University in Japan. “However, this species [stops attempting] such …