Santa Cruz, Calif.—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 .
The lab, led by UC Santa Cruz research scientist and adjunct professor Colleen Reichmuth, uses cooperative training methods to study behavior and physiology in marine mammals. Resident research animals, including Ronan, participate in a wide range of projects that help teams explore their amphibious subjects' inner worlds. Examples include studies on learning and memory, sensory biology, and diving physiology.
In other words, Ronan isn't just working on her rhythm everyday in the lab. The team estimates that, over the past 12 years, she has participated in about 2,000 rhythm exercises—each lasting just 10 to 15 seconds. And sometimes, years went by between these sessions while she focused on other areas of research.
"She definitely wasn't overtrained," Cook said. "Realistically, if you added up the amount of rhythmic exposure Ronan has had since she's been with us, it is probably dwarfed by what a typical 1 year old kid has heard."
Ronan's original rhythm study was inspired by work by Ani Patel, at Tufts University, along with colleagues who studied intermittent beat keeping in Snowball, a pet cockatoo who spontaneously "danced" to the Backstreet Boys . Because humans and cockatoos are both vocal mimics, the parrot work led to a theory that brain changes to support vocal learning were required for moving in time to music.
Sea lions haven't shown the ability to learn new vocalizations, so Ronan's 2013 study made a huge splash because it challenged the vocal-learning theory of rhythm. But in the study's wake, some prominent theorists in biomusicality claimed that her performance was not as precise and reliable as human performance.
They suggested that Ronan might not be doing exactly what humans were, and that, therefore, she could not rely on the same biological mechanisms for perceiving and moving in time to rhythm. That prompted Cook and Reichmuth to test Ronan again to see if she had improved, and to compare her performance to people performing a similar task with the same sounds.
What they found, as reported in today's new study, is that Ronan was more precise and consistent at every tempo they tested. And in a head-to-head battle of the beats with the UC Santa Cruz students, she more than held her own. The study's authors then used the students' performance to model the theoretical performance of 10,000 humans conducting the same rhythmic behavior.
Based on that model, Ronan was in the 99th percentile for beat-keeping reliability.
Now, at 170 pounds and age 16, the team says Ronan is "grown up and in her prime" for a female sea lion in managed care. Being with her day in and day out, over more than a decade, the researchers have become extremely attuned to Ronan. They know she is intelligent, but also exuberant. And just like us, her performance gets better with practice.
"One of the most important outcomes of the study is the fact that maturation and experience matter," Reichmuth said. " It's not just a test of rhythmic performance. It reflects her cognitive behavior and her ability to remember and refine it over time."
Another thing: Ronan also wants to perform well. Everytime she mounts her test platform, it's because she wants to, Reichmuth explained. If Ronan's not feeling it, there's no test that day. "She's motivated. To her, it's a game she knows how to win," Reichmuth said, "and she likes the fish that come with it."
Ronan's ripple effect
Ronan's research progression has had far-reaching impacts in the scientific community, contributing to a growing body of work in comparative cognition. Her journey from an eager and curious orphaned sea lion to a key figure in rhythm-perception studies has exceeded all expectations. Her abilities challenge existing paradigms about which species can perceive and produce rhythm, opening new doors for research on the cognitive capacities of animals.
The team's 2013 paper inspired follow-up studies across various species, including primates, elephants, birds, and yes, humans. As UC Santa Cruz researchers continue to analyze and share findings, they remain committed to fostering a broader understanding of rhythm perception across species—and Ronan's recent work will further that goal.
Not a fluke
Ronan's story is not just about one sea lion. A question Cook says he often hears is why can't dogs dance. Our canine companions are frequently exposed to music, and yet, they don't seem to respond with rhythmic movements like Ronan. Cook responds by asking his own question: How many people try to train their dog to dance in an explicit rhythm-based way?
The answer: not many. "If you're going to say dogs can't dance, you have to empirically assess that—really give the dog many opportunities to receive very precise feedback on rhythmic movement and see how they do," Cook said. "I would be very surprised if you couldn't get a border collie to do something like what Ronan does if you spend enough time on it."
But this isn't about teaching animals a cool party trick for fun. What Cook and researchers like him around the globe seek to better understand are the evolution of cognition, the universality of pattern recognition, and the intricate ways in which brains—both human and non-human—process the world around them.
"Ronan's new study highlights the importance of experience, maturity, and really fine-grained training in a controlled laboratory setting to assess these questions," Cook concludes.
Other co-authors of the paper include researchers Carson Hood and Andrew Rouse, who are also jointly affiliated with UC Santa Cruz's Institute of Marine Sciences and the New College of Florida.
