Science and Medicine

A red-winged blackbird sings at the Merritt Island National Wildlife Refuge in Titusville, Florida. A flock of more than 1,000 blackbirds rained on the small town of Beebe, Arkansas, baffling wildlife officials who said on Sunday the birds would be tested.

BEEBE, Ark.—Environmental service workers finished picking up the carcasses on Sunday of about 2,000 red-winged blackbirds that fell dead from the sky in a central Arkansas town.

Mike Robertson, the mayor in Beebe, told The Associated Press the last dead bird was removed about 11 a.m. Sunday in the town about 40 miles northeast of Little Rock. He said 12 to 15 workers, hired by the city to do the cleanup, wore environmental-protection suits for the task.

The birds had fallen Friday night over a 1-mile area of Beebe, and an aerial survey indicated that no other dead birds were found outside of that area. The workers from U.S. Environmental Services started the cleanup Saturday.

Robertson said the workers wore the suits as a matter of routine and not out of fear that the birds might be contaminated. He said speculation on the cause is not focusing on disease or poisoning.

Several hundred thousand red-winged blackbirds have used a wooded area in the town as a roost for the past several years, he said. Robertson and other officials went to the roost area over the weekend and found no dead birds on the ground.

Read more: Thousands of Dead Birds Picked up in Arkansas

Chimpanzee holding baby. Researchers have reported some of the first evidence that chimpanzee youngsters in the wild may tend to play differently depending on their sex, just as human children around the world do. (Credit: iStockphoto/Gabriela Schaufelberger)

Researchers have reported some of the first evidence that chimpanzee youngsters in the wild may tend to play differently depending on their sex, just as human children around the world do.

Scientists at Harvard University and Bates College say female chimpanzees appear to treat sticks as dolls, carrying them around until they have offspring of their own. Young males engage in such behavior much less frequently.

The new work by Sonya M. Kahlenberg and Richard W. Wrangham, described this week in the journal Current Biology, provides the first suggestive evidence of a wild nonhuman species playing with rudimentary dolls, as well as the first known sex difference in a wild animal’s choice of playthings.

The two researchers say their work adds to a growing body of evidence that human children are probably born with their own ideas of how they want to behave, rather than simply mirroring other girls who play with dolls and boys who play with trucks. Doll play among humans could have its origins in object-carrying by earlier apes, they say, suggesting that toy selection is probably not due entirely to socialization.

Read more: Young Female Chimpanzees Treat Sticks as Dolls