Female frogs communicate with males through blinking.

Blinking is a behavior unique to animal taxa with motile eyelids, such as most amphibians and reptiles as well as all birds and mammals. Eyelid movement has physiological functions, such as lubricating the cornea and washing away dust, but its potential signaling functions are not well understood. The use of eyeblinks as a social signal is currently thought to be restricted to some primates, especially humans and their companion animals, but has not been verified in other taxa. Here, through field observation and experiments, we demonstrate that female concave-eared torrent frogs (Odorrana tormota), which inhabit noisy streams, use eyeblinks to communicate with males to urge them to initiate amplexus for mating. Our findings reveal that eyeblinks may serve as a social signal in non-primate species.