Sea Lion Shows Non-Human Mammals Also Have Rhythm
SATURDAY, Feb. 15, 2014 -- Humans aren't the only ones who have rhythm and can keep a beat, according to new research on a musically inclined sea lion named Ronan.
In studying Ronan at the Long Marine Laboratory at the University of California, Santa Cruz (UCSC), scientists found that the mammal was able to bob her head in time with different types of music and other rhythmic sounds. The researchers concluded musical ability is not unique to humans and what it is that makes people musical may be shared with animals.
"People have assumed that animals lack these abilities. In some cases, people just hadn't looked," Peter Cook, a postdoctoral fellow at Emory University, said in a UCSC news release. "The comparative study of rhythm has undergone a renaissance in recent years, with new methods being attempted and new species tested," he added.
"It's exciting to be meeting with top scientists in the field at this crucial juncture," noted Cook, who began working with Ronan while he was a graduate student at UCSC.
Ronan was born in the wild in 2008, but a year later was found on Highway 1 in San Luis Obispo County in California. Rescuers from the Marine Mammal Center in Sausalito noted this was the third time the sea lion was found stranded and concluded she would not survive in the wild. In January 2010 Ronan joined the Pinniped Cognition and Sensory Systems Laboratory at UCSC.
Scientists at the lab acknowledged Ronan's intelligence and decided to have her participate in a study of beat keeping.
"From my first interactions with her, it was clear that Ronan was a particularly bright sea lion," Cook said. "Everybody in the animal cognition world, including me, was intrigued by the dancing bird studies, but I remember thinking that no one had attempted a strong effort to show beat keeping in an animal other than a parrot. I figured training a mammal to move in time to music would be hard, but Ronan seemed like an ideal subject."
The researchers were able to train Ronan to bob her head in time with rhythmic sounds as well as music she had never heard before.
"Given her success at keeping the beat with new rhythm tracks and songs following her initial training, it's possible that keeping the beat isn't that hard for her," Cook noted. "She just had to learn what it was we wanted her to do."
Aside from people, previous studies have only shown that parrots and other birds that can engage in vocal mimicry are capable of keeping a musical beat. "The idea was that beat keeping is a fortuitous side effect of adaptations for vocal mimicry, which requires matching incoming auditory signals with outgoing vocal behavior," Cook said.
Sea lions, however, are limited in the sounds they can make and are not known to be able to engage in vocal mimicry. Therefore, the researchers concluded complex vocal abilities aren't necessary to keep a beat.
"Ronan's success poses a real problem for the theory that vocal mimicry is a necessary precondition for rhythmic entrainment," Cook explained. "Along with other recent findings, this suggests that the neural mechanisms underpinning flexible beat keeping may be much more widely distributed across the animal kingdom than previously thought."
The study's findings were expected to be presented Saturday at the annual meeting of the American Association for the Advancement of Science, in Chicago.
The data and conclusions of research presented at meetings should be viewed as preliminary until published in a peer-reviewed journal.
Visit brainfacts.org to learn more about rhythm.
Posted: February 2014