RACINE — On a hot, sunny afternoon Thursday at the Racine Zoo, Angela Dassow is watching the white-handed gibbons watch themselves.
Put a mirror in front of the gibbons’ cage and they swing right up to the bars, hooting softly and peering at the glass, not knowing that every sound they make is part of a potentially historic study.
The white-faced male, Yule, starts to hoot softly. Dassow — blonde ponytail, sunglasses, tan — shakes her head. Not it.
The hot afternoon wears on, and suddenly the black-faced female, Robin, moves to the edge of the cage and starts hooting rhythmically. Dassow gives a big thumbs up. This is it.
Robin’s call escalates to a siren-like howl, which crescendos into a piercing scream. She swings around the cage as Yule calls back from the ground.
This is what University of Wisconsin-Madison Ph.D. student Dassow, 31, has been waiting for.
“These are sounds we could never get in the wild,” Dassow said, clearly excited. “The hope is we’d actually find language.”
“Language” has long been considered the exclusive purview of humans, said study coordinator Michael Coen, UW-Madison assistant professor of biostatistics and medical informatics. While people know that other animals communicate, Coen said this study provides “clear evidence” that many animals have similar linguistic structures to people, down to what resembles words, sentences and possibly syntax.
“Are they words as we know them? No. Does that mean that only human words are words? No, I don’t think so,” Coen said. “The bottom line would tentatively seem to be that language is far more universal than linguists believe.”
The gibbons at the Racine Zoo, 200 Goold St., are just two members of a worldwide study that includes dolphins, whales, rats, elephants, songbirds and the Racine gibbons’ wild relatives in Thailand.
Yule and Robin are acclimated to peoples’ presence, meaning Dassow can get much closer than in the wild, and her microphone can capture everything from the siren-like hoots that zoo neighbors can hear from blocks away, to the soft, child-like gasps that follow the apes’ loud calls. Some sounds have never been recorded in the wild, said Coen, and the zoo’s gibbons have a different “dialect” than those in Thailand, evidencing vocal learning.
Back in Madison, Dassow will compare the vocalizations from Racine’s captive gibbons with recorded calls from Thailand. The next step, she says, will be to return to Racine and play the wild calls for Robin and Yule, then see how the captive gibbons respond.
While the study has no definite timeline, its tentative findings have strong implications.
“They suggest we’re much less different from other species than we’d like to imagine,” Coen said.
Scientists trying to find ‘language’ in animals
MADISON — When Michael Coen started studying “language” in animals, he sought to abandon long-held assumptions and “approach animal sounds with no preconception of what I would find.”
Starting by analyzing zebra finch song, the University of Wisconsin-Madison assistant professor built on his dual computer and biological sciences background to analyze other animals using similar methods. He found that “they all seem to have the exact same thing” — a kind of linguistic structure previously considered unique to humans.
Coen’s analysis developed into an international study with around 20 collaborators worldwide recording and analyzing sounds, then comparing them using computer technology.
Researchers feed the different calls into a machine that analyzes them, allowing them to compile veritable dictionaries for each species. Comparing the same species from different parts of the world has even identified distinct dialects, much like comparing English spoken in Boston and Chicago.
Although Coen said this analysis has found clear evidence of word-like sounds, and even a kind of sentence structure, the “crown jewel” would be to identify syntax, something that could take years or might never be found.