Rhythmically trained sea lion returns for an encore -- and performs as well as humans

 Animal research on biomusicality, which looks at whether different species are capable of behaving in ways that show they recognize aspects of music, including rhythm and beat, remains a tantalizing field at the intersection of biology and psychology. Now, the highly trained California sea lion at UC Santa Cruz who achieved global fame for her ability to bob her head to a beat is finally back: starring in a new study that shows her rhythm is just as precise -- if not better -- than humans.

Ronan first shimmied onto the world stage in 2013, when researchers at the university's Long Marine Laboratory reported that, not only could she bob her head to a beat, but adjust her nods to tempos and music she hadn't heard before. In this new study, to be published on May 1 in the Nature journal Scientific Reports, Ronan's research team showed that her synchronization was as good or better than humans -- and that her consistency in performing the beat-keeping task was better than that of humans.

To best match Ronan's way of responding to a beat, a head bob, researchers asked 10 UC Santa Cruz undergraduates to move their preferred arm in a fluid, up-and-down motion to the beat of a percussive metronome. Three tempos were played -- at 112, 120, and 128 beats per minute -- with Ronan not previously exposed to 112 and 128 bpms.

At 120 bpm, Ronan's most practiced tempo, she on average hits within 15 milliseconds of the beat, according to the new study's lead author, Peter Cook, a longtime researcher with UC Santa Cruz's Institute of Marine Sciences. Ronan's variability in timing beat-to-beat is also around 15 milliseconds. By contrast, the blink of a human eye takes about 150 milliseconds.

"She is incredibly precise, with variability of only about a tenth of an eyeblink from cycle to cycle," said Cook, also a comparative neuroscientist at the New College of Florida. "Sometimes, she might hit the beat five milliseconds early, sometimes she might hit it 10 milliseconds late. But she's basically hitting the rhythmic bullseye over and over and over again."

The researchers emphasize that Ronan is in complete control of her participation. She is not deprived of food nor punished for choosing not to engage, and her training structure reflects this autonomy: She begins each session by climbing onto a designated ramp station, where she relaxes while waiting for the experiment to begin. Once ready, she positions herself and signals her readiness to start. If she chooses to disengage at any point, she is free to return to her pool without any negative consequences.

Recapping Ronan's career

Ronan was born in the wild in 2008, but stranded repeatedly due to malnutrition. After three such strandings, and being spotted walking down Highway 1 in 2009, regulatory agencies finally deemed her to be non-releasable. So UC Santa Cruz adopted her in 2010 and she became a permanent member of the Pinniped Lab.

Source: ScienceDaily