7 Scientific Studies About How Animals React to Music

Music is pretty universally enjoyed ... when it comes to people. Animals, on the other hand, have diverse reactions to tunes. For every Ronan the head-bopping sea lion, there are plenty of creatures that can't keep the beat. Here are seven scientific discoveries about how some animals react to music, either created by humans or themselves. 

1. DOGS IN KENNELS MIGHT BE LESS STRESSED WHILE LISTENING TO CLASSICAL MUSIC.

In a 2012 study [PDF] published in The Journal of Veterinary Behavior, researchers from Colorado State University monitored the behavior of 117 kenneled dogs, including their activity levels, vocalization, and body shaking. The researchers played a few different types of music to the dogs, including classical, heavy metal, and an altered type of classical music. They also observed the dogs' behavior when no music was playing at all. They found that the dogs slept the most while listening to all kinds of classical music, indicating that it helped them relax. The dogs had the opposite reaction to the metal music, which provoked increased body shaking—a sign of nervousness.

The researchers noted the similarities between dogs and people when it comes to classical music. “These results are consistent with human studies, which have suggested that music can reduce agitation, promote sleep, improve mood, and lower stress and anxiety,” they wrote. They also point out that heavy metal music has anxiety-inducing effects on some people as well.

2. CATS DON'T CARE ABOUT HUMAN MUSIC, BUT SCIENTISTS ARE ABLE TO CREATE MUSIC THAT THEY DO ENJOY. 

Cats either don't care for, or are pretty indifferent to, human music. Thankfully, Charles Snowdon, a psychologist at the University of Wisconsin-Madison, David Teie, a composer at the University of Maryland, and Megan Savage, formerly of the University of Wisconsin-Madison and now a Ph.D. student at SUNY-Binghamton, have developed music that contains frequencies and tempos similar to the ones cats use to communicate. We tested some of the songs on one of our editor's cats earlier this year; you can listen to samples of the songs here.

Snowdon and Savage went to 47 households with cats and played them music, including two classical songs and two songs developed for felines. When the researchers played the latter, the cat was more likely to move towards the speaker, or even rub up against it, according to their study, which was published in the journal Applied Animal Behavior Science earlier this year. Interestingly, young and old cats reacted to the cat songs the most positively. Middle-aged cats showed more indifference.

3. IT'S ALSO POSSIBLE TO MAKE MONKEY MUSIC.

Cats weren't the first animals Snowdon, Savage, and Teie made species-specific music for. In 2009, they developed songs that mirrored the pitch of monkey calls. For their study, which was published in the journal Biology Letters, the scientists played the music for tamarin monkeys. Songs that were inspired by the calming calls the animals make caused the monkeys to relax; they even ate more while listening to those songs. But when the researchers played music that contained sounds similar to ones the monkeys make when they’re expressing fear, the monkeys became agitated. (You can listen to the songs here.) The monkeys were mostly indifferent to human music—their behavior didn't noticeably change when they were listening to Nine Inch Nails, Tool, or Samuel Barber. But, interestingly, when they heard “Of Wolf and Man” by Metallica, they grew calmer.

4. COWS PRODUCE MORE MILK WHEN THEY'RE LISTENING TO RELAXING MUSIC. 

In 2001, researchers at the University of Leicester played various songs to 1000-strong herds of Friesian dairy cows. Over a period of nine weeks, the researchers alternated between fast music, slow music, and silence for 12 hours each day. They found that calming music—like R.E.M.'s "Everybody Hurts," Simon & Garfunkel's "Bridge Over Troubled Water," and Beethoven's "Pastoral Symphony"—actually resulted in the cows producing 3 percent more milk—0.73 liters per cow per day. One of the lead researchers, Dr. Adrian North, told the BBC, “Calming music can improve milk yield, probably because it reduces stress.” The cows were not so into “Space Cowboy” by Jamiroquai or “Size of a Cow” by Wonderstuff.

5. ELEPHANTS MIGHT BE BETTER AT PLAYING MUSIC THAN HUMANS ARE.

Elephants are already known for their ability to paint with their trunks, but it turns out that they might be musically inclined as well. (Just check out this viral video of elephants swaying their trunks to violin music!) In northern Thailand, a conservationist named Richard Lair put together the Thai Elephant Orchestra, in which 16 elephants play specially developed instruments like steel drums and even harmonicas. Neuroscientists who have studied the music of the Thai Elephant Orchestra have determined that the animals are able to keep a very stable tempo on a large drum—even more stable than a human can.

6. BIRD BRAINS REACT TO MUSIC IN A MANNER SIMILAR TO HUMAN BRAINS. 

Birds are probably the most well-known singers of the animal kingdom. A few years ago, researchers at Emory University set out to learn whether birds are actually making music, like humans do. To find out, they examined the brains of both male and female white-tailed sparrows as they listened to the sounds of male birds.

When humans listen to music, our amygdalae often light up in response. It turned out that female white-tailed sparrows had similar brain responses to the bird sounds. The part of their brain that’s similar to the amygdala lit up while listening to the male’s song. The male birds, on the other hand, had brain reactions similar to when humans listen to music they don’t like. Sarah Earp, the study's lead researcher, explained, “We found that the same neural reward system is activated in female birds in the breeding state that are listening to male birdsong, and in people listening to music that they like.”

7. FISH KNOW THE DIFFERENCE BETWEEN COMPOSERS.

In 2013, a study was published in the journal Behavioral Processes that revealed that goldfish could be trained to distinguish between composers. Researchers at Keio University used pieces of music by two composers in the study: Igor Stravinsky and Johann Sebastian Bach. The goal was to train the goldfish to gnaw on a ball filled with food when the correct composer’s music was playing. One group of fish got Stravinsky and a separate group got Bach. When the fish heard music, they went to gnaw on the ball and were rewarded with food. Once the fish were correlating a composer’s music with the reward, the researchers tried playing the other composer’s music. The goldfish didn’t gnaw on the ball at that point, indicating that they knew enough about the pitch and timbre of their composer to not associate the novel music with food.

All images courtesy of iStock