Bats Follow Musical Rules When Writing Love Songs

Making a mix of love songs for your special someone? Looking for something lively to slip in between Sonny and Cher's "I Got You Babe" and The Temptations' "My Girl"? I highly recommend a little number called "Chirp-Buzz-Buzz" by...a group of Brazilian free-tailed bats.

Turns out that bats are quite the romantic crooners, using "love song" vocalizations to attract females (and in some cases, to scare away intruding males). According to a new study*, their love songs are more complex than previously thought and have a number of musical rules. The researchers—from the Department of Biology at Texas A&M University, the Section of Neurobiology at the University of Texas at Austin and Bat World, a bat sanctuary and rehabilitation center in Mineral Wells, Texas—spent close to four years recording and analyzing the songs of two populations of Brazilian free-tailed bats (also known as Mexican free-tailed, scientific name Tadarida brasiliensis). The first group was a captive colony of about 60 bats in Austin, maintained by one of the study's authors. The second group was a wild colony of approximately 100,000 to 250,000 bats within Texas A&M's athletic complex in College Station.

After examining a total of 412 songs from 33 bats and comparing song variation within and across individuals and between the two different colonies, the researchers determined the male bats use several types of syllables with  individual sounds to create three easily recognizable phrases:

Chirps are complex phrases composed of "A" and "B" syllables**.
Trills are composed of short (mean = 3.4 ms) downward FM syllables that can be connected or are separated by short silent intervals.
Buzzes are composed of short (3 ms) downward FM syllables that are never connected.

These phrases, in turn, are used in different combinations to produce songs. The researchers found that particular phrase sequences kept coming up and identified several rules governing phrase order:

1) Songs begin almost exclusively with chirps.

2) Trills do not follow buzzes, but instead always follow chirps or another trill.

3) The majority of buzzes (90%) are followed by another buzz or occur at the end of the song (songs containing a buzz ended in a buzz 84 % of the time).

This may not seem like very impressive music theory, but complex songs and specific structural "language rules" are rare among mammals; previous mammalian research hasn't gone much further than determining that song elements are used in a non-random order. These bats' songs and the rules that govern them, though, may be "more analogous to those of some birds than to other mammals," say they researchers. Birds and their songs have long been the basis for understanding vocal production and the evolution of vocal complexity as well as the physiology of vocal production. With this new study, there's a foundation for future research into mammalian vocals, "a model not only to study communication similarities in other animals, but also human speech," says lead author Kirsten M. Bohn.

Here's a video featuring the vocal stylings of Sid the bat, with commentary by researcher Dr. George Pollak:

* Bohn KM, Schmidt-French B, Schwartz C, Smotherman M, Pollak GD. (2009). Versatility and Stereotypy of Free-Tailed Bat Songs. PLoS ONE 4(8):e6746. doi:10.1371/journal.pone.0006746

** "A" syllables are short (5 ms) downward frequency modulated (FM) sweep syllables. "B" syllables are longer (17ms) and more complex, often beginning with an upward FM followed by a longer downward FM and sometimes ending with another upward FM.

Quick True/False: World Capitals
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10 Pats Born on St. Patrick's Day
A photo from the 1919 wedding of Princess Patricia of Connaught to the Hon. Alexander Ramsay.
A photo from the 1919 wedding of Princess Patricia of Connaught to the Hon. Alexander Ramsay.
Bain News Service - Library of Congress, Public Domain, Wikimedia Commons

Need some St. Patrick's Day conversation fodder that doesn't involve leprechauns or four-leaf clovers? Ask your friends to name a "Pat" born on St. Patrick's Day. If they can't, they owe you a drink—then you can wow them with this list of 10.


Princess Patricia was the granddaughter of Queen Victoria, who gave up all of her royal titles when she married a commoner. She was born at Buckingham Palace on March 17, 1886.


The Dallas star was born on March 17, 1949. And here's a totally random fact about Duffy: His nephew is Barry Zito, former MLB pitcher for the Oakland Athletics and the San Francisco Giants.


Pattie Boyd
Larry Ellis, Express/Getty Images

Pattie Boyd is well-known to lovers of classic rock: She has been married three times, including once to George Harrison and once to Eric Clapton, who both wrote a couple of the most romantic songs in rock history in her honor (including The Beatles's "Something" and Clapton's "Wonderful Tonight"). Boyd was a model when she met Harrison on the set of A Hard Day's Night in 1964; the pair were married two years later. They divorced in 1977 and she married Clapton, Harrison's close friend, in 1979. She also had an affair with Ronnie Wood of the Rolling Stones toward the end of her marriage to The Quiet Beatle.


Belfast-born Pat Rice is a former footballer and coach who spent the bulk of his career with Arsenal F.C. (that's "football club," a.k.a. soccer to us Americans). He joined the Gunners in 1964 as a mere apprentice, turning pro a couple of years later. He became captain in 1977 and left the club for a few years in the early 1980s to go to Watford, but returned after he retired from playing in 1984. In 2012, after nearly 30 years with the organization, he announced his retirement.


Patty Maloney is an actress with dwarfism who stands just three feet, 11 inches tall. She has appeared in many movies and T.V. shows over the years, including operating the Crypt Keeper puppet in Tales from the Crypt. She also played Chewbacca's son Lumpy in The Star Wars Holiday Special.


Michael C. Hall and Mathew St. Patrick in 'Six Feet Under'

Ok, so Mathew St. Patrick is the stage name of the actor, but he was born Patrick Matthews in Philadelphia on March 17, 1968. You probably know him best as David's boyfriend Keith on Six Feet Under.


He may not be a household name, but the recording artists Patrick Adams writes for and helps produce certainly are. Adams has been involved in the careers of Salt-N-Pepa, Sister Sledge, Gladys Knight, Rick James, and Coolio, among others.


It's possible you look at Patrick McDonnell's work every day, depending on which comics your newspaper carries. McDonnell draws a strip called Mutts featuring a dog and a cat named Earl and Mooch, respectively. Charles Schulz called it one of the best comic strips of all time.


 Singer/Guitarist Billy Corgan of Smashing Pumpkins performs onstage during Live Earth New York at Giants Stadium on July 7, 2007 in East Rutherford, New Jersey
Evan Agostini, Getty Images

Yes, you know him better as just plain old Billy Corgan: he's the face of the Smashing Pumpkins, engages in public feuds with Courtney Love, and maybe once dated Jessica Simpson. He made his debut on March 17, 1967.


Patricia Ford is a retired model probably best known for her Playboy photoshoots in the 1990s.


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