Bruce has done something scientists did not expect. The parrot, missing his upper beak, became the alpha male of his group, or circus.

The New York Times reported the finding from a study published in Current Biology, which researchers said showed the inventiveness of disabled animals.

Bruce is a 13-year-old kea, a species found only in New Zealand. He likely lost his upper beak while trying to get food from a rat trap, which made it nearly impossible for him to survive in the wild. Researchers rescued him and took him to the Willowbank Wildlife Reserve, where scientists visited his circus to study the birds’ intelligence.

Bruce wanted to join the experiments, but his missing beak made that difficult. Scientists later noticed he was holding a pebble between his tongue and lower beak and running it through his feathers. In the absence of an upper beak, which keas use to preen themselves, Bruce had found a way to clean his feathers. The study said the behavior had not been observed at any other time within the species.

Years later, Bruce surprised scientists again. Male keas typically bite rivals around the neck to assert superiority. Bruce could not bite, so he established dominance with an unconventional fighting technique, using his lower beak in a maneuver scientists called “jousting.”

Male keas fight for dominance, and losing causes them to feel stress. The alphas have low stress because they do not lose. During stress tests, scientists found Bruce’s levels were the lowest, meaning he was at the top.

“We haven’t been tracking his dominance and stress over the last 12 years to know the journey that he’s been on,” said Alex Taylor, the director of the Animal Minds Lab at Universitat Autònoma de Barcelona, according to the Times. “We weren’t really looking for it, so we didn’t really join the dots.”

“The link between innovation and disability in animals is important and completely understudied,” said Alice Auersperg, a cognitive biologist at the University of Veterinary Medicine Vienna who was not involved in the study.

Sarah Turner, a primatologist at Concordia University in Montréal who was not involved in the study, said research on other species matches the findings that animals with disabilities sometimes come up with ingenious ways to thrive.

The study authors also said Bruce’s success “brings into question whether well-intentioned prosthetic assistance for physically impaired animals will always improve positive animal welfare.”

“The world is a living lab now,” Turner said.

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