Bats communicate and share information in more ways than earlier known to scientists, as per a new research conducted at the Bat Lab for Neuro-Ecology at Tel Aviv University. During their analysis of bat squeaking, the research team found different tones for calls related to food, sleep or mating. The research team said that they still need to decipher many of the signals but they are sure that there are lot of different signals that bats use for communication.
Dr. Yossi Yovel, a neuro-ecologist at Tel Aviv University informed that the cacophony created by a group of bats actually contains lot of information that bats exchange. Yovel added that all the loud vocalization that was earlier categorized as one type of calls could be divided into different signals bats use for communication.
Yovel and his team was able to ascertain certain calls which were between two individual bats. The Israeli research team analyzed 15,000 bat vocalizations. During their research project that continued for two and a half months, Yovel was helped by Yosef Prat and Mor Taub.
The current study was conducted on Egyptian fruit bats. The research team said that the bats were communicating individually instead of broadcasting the message to the whole group. This is interesting as earlier research has classified all bat calls as aggressive vocalization. Dr. Yovel added that Egyptian bats argue a lot and they also have different vocalization for calls related to food and sleep. Their team also noticed vocalizations of females who were trying to avoid mating with certain males. The protest against mating attempts was quite surprising for research team led by Dr. Yoval.
Dr. Yovel added that their research project aimed at understanding more about animal communication. Researchers are still away from deciphering communication skills used by animals.
"We have shown that a big bulk of bat vocalisations that previously were thought to all mean the same thing, something like ‘get out of here!’ actually contain a lot of information," lead researcher, Yossi Yovel, from the Tel Aviv University.
"Animals make sounds for a reason," Whitlow Au, from University of Hawaii, who wasn’t involved in the research, informed Nature magazine. "Most of the time, we don’t quite understand those reasons."
The research team informed, "Our finding might be akin to a human speaker who uses varying intonation towards different listeners (e.g. male vs. female addressees) while using the same words."
"The importance of vocal communication increases when vision is limited (e.g. in dense forests or underwater), thus it is reasonable to assume that the vocalizations of a social mammal, which roosts in dark caves, will evolve to convey elaborate information about the interactions between individuals," the researchers added.
The research paper has been published in the journal Scientific Reports.
"Identifying context specific calls can be a first step toward the recovering of meaning in animal communication," the researchers write. "Understanding the encapsulated information in animal vocalizations is central to the study of sociality, communication, and language evolution."
"Nearly all of the communication calls of the Egyptian fruit bat in the roost are emitted during aggressive pairwise interactions, involving squabbling over food or perching locations and protesting against mating attempts," the researchers write.