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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.

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A Simple Trick For Figuring Out the Day of the Week For Any Given Date
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People typically remember anniversaries in terms of dates and years, not days of the week. If you can’t remember whether you got married on a Saturday or Sunday, or don't know which day of the week you were born on, there’s a simple arithmetic-based math trick to help you figure out sans calendar, according to It's Okay To Be Smart host Joe Hanson.

Mathematician John Conway invented the so-called Doomsday Algorithm to calculate the day of the week for any date in history. It hinges on several sets of rules, including that a handful of certain dates always share the same day of the week, no matter what year it is. (Example: April 4, June 6, August 8, October 10, December 12, and the last day of February all fall on a Wednesday in 2018.) Using this day—called an “anchor day”—among other instructions, you can figure out, step by step, the very day of the week you’re searching for.

Learn more about the Doomsday Algorithm in the video below (and if it’s still stumping you, check out It’s OK to Be Smart’s handy cheat sheet here).

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There May Be an Ancient Reason Why Your Dog Eats Poop
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Dogs aren't known for their picky taste in food, but some pups go beyond the normal trash hunting and start rooting around in poop, whether it be their own or a friend's. Just why dogs exhibit this behavior is a scientific mystery. Only some dogs do it, and researchers aren't quite sure where the impulse comes from. But if your dog is a poop eater, it's nearly impossible to steer them away from their favorite feces.

A new study in the journal Veterinary Medicine and Science, spotted by The Washington Post, presents a new theory for what scientists call "canine conspecific coprophagy," or dogs eating dog poop.

In online surveys about domestic dogs' poop-eating habits completed by thousands of pet owners, the researchers found no link between eating poop and a dog's sex, house training, compulsive behavior, or the style of mothering they received as puppies. However, they did find one common link between the poop eaters. Most tended to eat only poop that was less than two days old. According to their data, 85 percent of poop-eaters only go for the fresh stuff.

That timeline is important because it tracks with the lifespan of parasites. And this led the researchers to the following hypothesis: that eating poop is a holdover behavior from domestic dogs' ancestors, who may have had a decent reason to tuck into their friends' poop.

Since their poop has a high chance of containing intestinal parasites, wolves poop far from their dens. But if a sick wolf doesn't quite make it out of the den in time, they might do their business too close to home. A healthier wolf might eat this poop, but the parasite eggs wouldn't have hatched within the first day or two of the feces being dropped. Thus, the healthy wolf would carry the risk of infection away from the den, depositing the eggs they had consumed away in their own, subsequent bowel movements at an appropriate distance before the eggs had the chance to hatch into larvae and transmit the parasite to the pack.

Domestic dogs may just be enacting this behavior instinctively—only for them, there isn't as much danger of them picking up a parasite at home. However, the theory isn't foolproof. The surveys also found that so-called "greedy eaters" were more likely to eat feces than dogs who aren't quite so intense about food. So yes, it could still be about a poop-loving palate.

But really, it's much more pleasant to think about the behavior as a parasite-protection measure than our best pals foraging for a delicious fecal snack. 

[h/t The Washington Post]

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