【推荐1】Male cockatoos (风头鹦鹉) might be the rock stars of the animal kingdom-but unsurprisingly, they mainly just do it for the female.

The Australian bird is the only animal other than humans known how to make tools to compose music, a new study says. While other animals, such as chimpanzees, enjoy drumming on sticks and logs, they don’t make their own musical tools to do it.

Robert Heinsohn, a biologist at Australia National University, first witnessed the behavior in male cockatoos in northern Australia in 1997. Then, he spent the next two decades videotaping the shy animals to find out if their drumming was truly music—defined as regular beat production, repeated components, and, of course, personal style. By analyzing the beats made by the birds, he found that the sounds were highly predictable, just like human music that had a unique style. “The cockatoo was holding what looked like a stick and beating it on the tree branch, and every so often he would pause and let out either a long whistle or a sharp scream,” he said.

Importantly, male cockatoo primarily started drumming when they were around females—about 70 percent of the time, according to his research, published this week in the journal Science.

But Heinsohn did not found the females’ reactions to the males’ music and the male cockatoos didn’t dance, either, while they produced their own unique beats-an activity that usually goes hand in hand with music for many animals in love, such as swans, cranes and birds of paradise.

So Heinsohn thought such behavior may not be learned for courtship (求爱). “It seems that they are open to the pleasure of rhythm, just like humans,” he says. “As soon as one male works out a pleasing drumming rhythm that gets the approval from the females, they would stay together to enjoy it.”

【推荐3】Human rubbish can be a cockatoo’s treasure. In Sydney, the birds have learned how to open dustbins and throw rubbish around in the streets as they hunt for leftovers. People are now fighting back.

When cockatoos learn how to open dustbin lids, people change their behavior, using things like bricks to weigh down lids (盖子), to protect their trash from being thrown about. That’s usually a low-level protection and then the cockatoos figure out how to defeat that. That’s when people strengthen their efforts, and the cycle continues.

Tricks such as attempting to scare the parrots off with rubber snakes don’t work very well. Nor does blocking access with heavy objects such as bricks; cockatoos use force to push them off. Hanging weights from the front of the lid or placing items such as sneakers and sticks through a bin’s back handles work better. Researchers didn’t see any birds get inside bins with these higher levels of protection.

The findings suggest an arms race, but the missing piece is how the birds will respond as people try new ways of blocking bins. Some survey responses suggest that the parrots are learning.

Cockatoos may stay away from strategies that take too long to beat. Bricks, for instance, are easy to quickly push off a bin; breaking sticks placed through the bin’s back handle could take more time. Perhaps if enough people in a neighborhood adopt a highly effective method, Clark, a behavioral ecologist says, the cockatoos may not find it worth it to stop by.