Bats have longer memories than some people think. The fringed-lipped bat (Trachops cirrhosus) feeds on insects and frogs it finds by following their mating calls. The animals have learned to distinguish between the calls of different frog species in order not to eat poisonous prey. Now there are indications of how long the bat brain stores this information, as a team reports in the magazine Current Biology.
To test memory, May Dixon of the University of Texas at Austin and her colleagues trained wild-caught bats to respond to a specific ringtone. To do this, they had the animals attack small fish that were placed on a speaker. The team then released the bats into the wild and recaptured eight of them between one and four years later.
To test whether they would remember their training, the eight bats heard the ringtone again. Almost all previously caught animals then pounce on their prey, while wild-caught, untrained bats mostly just twitched their ears.
The researchers say that remembering sounds, even years later, could help bats hunt rare prey or find frogs to mate with.