Study Shows Tadpoles Quarantine Sick Peers

NEW HAVEN, Conn. — A new study shows that some animal species may instinctively sense when peers are sick and form their own sort of natural quarantine.

David Skelly, professor of ecology and evolutionary biology at Yale University, and Joseph Kiesecker, professor of ecology at Penn State University, studied the behavior of bullfrog tadpoles. They found that healthy amphibians could detect odors given off by infected peers and avoided getting too close.

“What this shows is that animals can recognize risks in the environment and respond in ways that reduce that risk,” Skelly said.

In the study, published in Proceedings of the National Academy of Sciences, the scientists injected tadpoles with a fungus that attacks the digestive system. When an infected tadpole was placed near tadpoles without the disease, the healthy ones squirmed away, some as far as a foot. “Identifying the cue is the logical next step,” Skelly said.