By Virginia Morell
Helping others is such an essential part of being human that we’ve developed elaborate rituals—and biblical edicts—for protecting kin and sheltering strangers. Yet aside from humans, only a few other species, including orangutans and bonobos, seem to willingly help others. Now, scientists say they’ve found the first nonmammals that are also altruists: African gray parrots.
Past studies suggest some birds are prickly creatures. For example, crows—known for their intelligence—would not help other crows earn a nut reward, as parrots do for each other in the new study. The parrot study is “striking,” says Karl Berg, an avian ecologist and wild parrot expert at the University of Texas, Rio Grande Valley, despite the small numbers of birds in the study. Berg was not involved in the research.
To find out whether African gray parrots or blue-headed macaws—two exceptionally brainy species—would assist their fellows, animal cognition scientists with the Max Planck Institute for Ornithology’s Comparative Cognition research station, tested four and three pairs, respectively. They first taught the captive birds to exchange a token with a researcher for a nut reward (above).
Birds of both species succeeded. But only the African grays aced the next test. The researchers gave tokens to only one bird—which didn’t have access to the researcher or the reward. But the bird could reach its partner through a small window, and the partner could then exchange the tokens for a treat. The catch? Only the partner got to eat.
In both species, the bird lacking the tokens often uttered soft cries to get their partner’s attention. But the blue-headed macaws hopped away, ignoring the cries for help. In contrast, the African grays seemed to know that help was needed even without a reward: Seven out of eight gave their partners their tokens in the very first trial, the scientists report today in Current Biology. When the roles were reversed, the new donors generously passed their tokens to their former helpers, suggesting the grays have some understanding of reciprocity.
What’s more, the grays would give even if their partner wasn’t a close friend or relative. If it was, the donor bird would give even more tokens. (Meanwhile, some macaws made it very clear they didn’t want a partner at all: When they were given an opportunity to feed from a shared bowl, the dominant bird grabbed it with his beak and dragged it away.)
The difference between the two species’ responses may be due to their different social organizations, with grays living in large, ever-changing flocks, and macaws in smaller groups, the researchers suggest. But Berg notes that little is known about the natural behaviors of either bird. (Both are endangered in the wild.) Further, it may be that the African grays were inclined to share because some of them were not only friends but siblings who share genes. That means they would have been “helping themselves via helping each other,” something that happens naturally in the wild. Still, Berg adds that the new experiments offer “considerable insight into altruism and reciprocity” in African gray parrots.
Source: Science Mag