In Finding Nemo, Dory claims to “speak whale”. The idea is ridiculous because (besides all the other reasons) there are so many different whale species, it's hardly likely they would all speak one language. Species as distant from each other as humans are from chimpanzees don't have much to communicate. Yet Pixar may have been onto something. It seems that bats, as wonderfully diverse as cetaceans, can learn from members of species with which they share very distant relationships.
Bats are usually social creatures, roosting in large colonies. One reason for group living is the opportunities for education. “Learning from others can be especially beneficial because it can save time and energy otherwise spent on trial-and-error learning and reduce the odds of making costly mistakes,” a paper in Science Advances points out.
Bats have made great use of this, with most of the 1,300 living species using vocal and chemical cues to communicate. When a predator threatens, one colony member will send up the bat signal, causing others to take to the skies. They also take lessons on good sources of food.
First author Dr Krista Patriquin of the University of Toronto tested whether fringe-lipped bats (Trachops cirrhosus) are able to learn from white-throated round-eared bats (Lophostoma silvicolum), as well as members of their own species. The two types of bats often live in mixed-species groups, but are too distantly related to even be classified as the same genus. Both hunt in forest understories also popular with more than a dozen other bat species.
The two types of bats seldom interfere with each other. Fringe-lipped bats prefer frogs, only eating katydids (the round-eared bats' preferred food) when amphibians are sparse. Moreover, even when they do eat katydids, fringe-lipped bats usually prefer different species of the grasshopper-like insects. Both bats hunt by listening to their prey's mating calls, and it seems each has become attuned to the sounds their preferred dinners make.
Patriquin played calls from katydids to bats held in cages and fed them small fish (another food fringe-lipped bats like) when they swooped on the broadcasting speakers in search of a meal, rather than a dummy speaker used for distraction.
Confronted with unfamiliar katydid calls, it took awhile for fringe-lipped bats to learn to associate them with food. Progress was much quicker, however, when a bat new to the game had the opportunity to listen in on the echolocation calls made by more experienced bats or to watch them hunt. Most fringe-lipped bats learned just as well from members of the other species as they did from their own. However, one of Patriquin's bats refused to pay attention to white-throated round-eared bat calls, proving there are bigots everywhere.
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