Science / Medicine : Asian Bees Have Cool Habit

Thousands of Asian bees leave their nests together to defecate--producing “yellow rain” that the U.S. government once claimed was a Soviet biological weapon--to cool themselves and their nests, scientists say.

By relieving themselves of hot feces equal to one-fifth of their body weight, the honeybees are able to cool their nests more efficiently and help their offspring grow, the researchers said in last week’s issue of Nature, a British science journal.

In a 1981 speech and 1982 report, then-Secretary of State Alexander Haig Jr. asserted that “yellow rain” was a Soviet biological weapon used to kill thousands of people in Cambodia, Laos and Afghanistan during the previous decade.

The claim later was discredited by scientists who proved the yellow deposits were bee droppings, although the State Department never retracted the claim, said biologist Peter G. Kevan of the University of Guelph, Canada. The latest study found why the Asian honeybees make what scientists call “mass defecation flights,” Kevan said.