Featured Research

from universities, journals, and other organizations

How Singing Bats Communicate

Date:
October 19, 2007
Source:
Texas A&M University
Summary:
Bats are the most vocal mammals other than humans, and understanding how they communicate during their nocturnal outings could lead to better treatments for human speech disorders. Thousands of bats native to Central Texas fly overhead each night singing songs of complex syllables -- but at frequencies too high for humans to hear.

Researchers are trying to understand how Mexican Freetail bats organize syllables into songs and how their communication is linked to the brain.
Credit: Image courtesy of Texas A&M University

Bats are the most vocal mammals other than humans, and understanding how they communicate during their nocturnal outings could lead to better treatments for human speech disorders, say researchers at Texas A&M University.

Related Articles


Thousands of bats native to Central Texas fly overhead each night singing songs of complex syllables -- but at frequencies too high for humans to hear.

Texas A&M researcher Michael Smotherman is trying to understand how Mexican Freetail bats organize syllables into songs and how their communication is linked to the brain. "If we can identify those areas in a bat brain [responsible for communication], we can learn more about how a normal [human] brain generates and orchestrates complex communication sequences," Smotherman says. "And by understanding how that works, we can then come up with testable hypotheses about what might be going on in speech disorders."

The researchers in Smotherman's lab are studying two aspects of bat communication. In behavioral studies, they examine sex differences and seasonal variations in communication, and in physiology studies they try to locate the parts of the bat brain active during communication.

Mexican Freetail bats sing mostly in ultrasonic frequencies that are right above the upper limit of human hearing. Humans can sometimes hear little bits of bat songs, however, when parts of syllables drop low enough.

Bats communicate at such high frequencies because of their ability to echolocate, which means they project sound and use the echoes to determine the direction and distance of objects. As the frequency of the bat's sound gets higher, it can detect a more detailed picture of its surroundings.

Smotherman says Mexican Freetail bats use between 15 and 20 syllables to create calls. Every male bat has its own unique courtship song. The pattern of all courtship songs is similar, but each male bat uses a different syllable in its distinctive song. Bats also use sophisticated vocal communication to draw territorial borders, define social status, repel intruders, instruct offspring and recognize each other.

"No other mammals besides humans are able to use such complex vocal sequences to communicate," Smotherman says.

The songs bats sing are similar to bird songs. Scientists have understood the link between bird songs and the bird brain for years, but "the architecture of a bird brain is very different from that of a mammal brain," Smotherman explains, "so it is difficult to apply knowledge about bird communication to human speech."

The brains of all mammals are organized in basically the same way, so a bat brain has many of the same structures as a human brain. This makes it easier to infer things about human speech from studying bat communication. The researchers' first goal is to locate the part of the bat brain responsible for singing. "The bat brain has to have some higher vocal center that's responsible for organizing these [vocal] sequences and patterns, and we just don't know where it is yet," Smotherman says. "So we're using molecular techniques to identify which regions of the brain are most active during singing."

Smotherman and his team maintain about 75 bats in their lab. They usually collect the bats from schools and churches that report bats in their buildings. "[By doing this,] we don't have to feel like we're taking them out of the wild," Smotherman says. He adds that the bats are not aggressive and are a "fantastic bat for the lab because they are quite friendly."

Smotherman hopes that over the next decade, the group can apply its research to knowledge of human speech and help shed light on language disorders. "The fact that human speech is so unique has really constrained research in this area," Smotherman says. "Compared to other areas of neuroscience, we're way behind in understanding even the most basic issues of how [speech] works."


Story Source:

The above story is based on materials provided by Texas A&M University. Note: Materials may be edited for content and length.


Cite This Page:

Texas A&M University. "How Singing Bats Communicate." ScienceDaily. ScienceDaily, 19 October 2007. <www.sciencedaily.com/releases/2007/10/071018123525.htm>.
Texas A&M University. (2007, October 19). How Singing Bats Communicate. ScienceDaily. Retrieved February 26, 2015 from www.sciencedaily.com/releases/2007/10/071018123525.htm
Texas A&M University. "How Singing Bats Communicate." ScienceDaily. www.sciencedaily.com/releases/2007/10/071018123525.htm (accessed February 26, 2015).

Share This


More From ScienceDaily



More Mind & Brain News

Thursday, February 26, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Sleeping Too Much Or Too Little Might Increase Stroke Risk

Sleeping Too Much Or Too Little Might Increase Stroke Risk

Newsy (Feb. 26, 2015) People who sleep more than eight hours per night are 45 percent more likely to have a stroke, according to a University of Cambridge study. Video provided by Newsy
Powered by NewsLook.com
Mayor Says District of Columbia to Go Ahead With Pot Legalization

Mayor Says District of Columbia to Go Ahead With Pot Legalization

Reuters - News Video Online (Feb. 25, 2015) Washington&apos;s mayor says the District of Columbia will move forward with marijuana legalization, despite pushback from Congress. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Marijuana Nowhere Near As Deadly As Alcohol: Study

Marijuana Nowhere Near As Deadly As Alcohol: Study

Newsy (Feb. 25, 2015) A new study says marijuana is about 114 times less deadly than alcohol. Video provided by Newsy
Powered by NewsLook.com
Researchers Replace Damaged Hands With Prostheses

Researchers Replace Damaged Hands With Prostheses

Newsy (Feb. 25, 2015) Scientists in Austria have been able to fit patients who&apos;ve lost the use of a hand with bionic prostheses the patients control with their minds. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins