All in the Family:
Tent-making Dog-faced bats. Photo courtesy of Doug Locke Photography.
Imagine how loud the chattering can get in a cave of 20 million or more bats! Over time, scientists began to wonder: How could a mother bat decipher which bat pup is hers to feed? Because it is a mammal, female bats give birth to live young, just as other female mammals do, and continue to nurse the newborn until the baby is grown. It is standard for a female bat to have one pup, but twins are common in some species and as many as three or four pups born at the same time are common in others. Upon returning after a night out of hunting for her baby roosting back in the cave with the other 20 million inhabitants, a mother bat can zero in on her baby by calling to it, almost like calling out her baby bat's name. The baby bat hears the call of its mother and then calls back to her, letting her know where the baby is. Scientists long believed that mother bats would return to the nursery every few hours to nurse any of the pups; however, research proved that bat mothers locate their own bat pups by a distinctive voice call used by the pup, as well as by the pup's distinct smell. Another interesting form of communication among female bats is their ability to group together in nursery colonies, special areas in caves where females go to give birth. After they have given birth, mother bats of the same species place their newborns in a group called a crèche, a nursery colony where thousands of furless newborn bats hang together from the walls and ceilings.
Female bats in a maternity colony.
Recent research is further proving that all bats, just like mothers to babies, can recognize the calls from particular individuals just like humans can recognize the voices of friends and family members. When bats hear echolocation calls from their own species, they call back with a special vocalization that carries an individual tone recognized by the receiving bat. Researchers think that those particular bat calls represent some form of greeting, similar to a specific human voice saying, "Hello, Bob. It's me… Brian." Bats not only recognize family members and friends by echolocation calls, they can also clearly distinguish calls from their own species versus calls from foreign species, just like humans are able to recognize different languages. Scientists have conducted studies and report that such language results are really interesting, and immediately open doors for further investigation and follow-up experiments. Learning more about language and the intricate communication systems used to communicate throughout bat communities is proving to have many advantages.