SSS 2008-02-05

（单词翻译）

This is Scientific Americans' 60-Second Science. I’m Cynthia Graber. This’ll just take a minute.

When is an ant like a piece of fruit? When it’s infected by a parasite¹. Researchers affiliated² with the Smithsonian Tropical Research Institute discovered this bizarre occurrence in Central America as they were studying the gliding³ ability of a certain species of ant. They found some colony members with bright red swollen⁴ abdomens⁵. The scientists took specimens⁶ back to the lab and discovered they were full of hundreds of nematode eggs. The bright red bellies⁷ look suspiciously like the brilliant red and pink berries that proliferate⁸ in the rainforest. Researchers think that the nematode makes the ant look like fruit to get birds to eat the ants. Birds usually keep the ants off their menu because of armor and a bad chemical taste. The birds then spread parasite eggs in their droppings. Ants forage⁹ through bird droppings for seeds. They feed the infected droppings to ant larvae¹⁰ beginning the infection process all over again. The red-bellied ant is the first known case of a parasite causing fruit mimicry¹¹. One of the researchers was surprised to that something dumb as a nematode can manipulate its host in such a sophisticated way, but evolution works no matter how dumb organisms are.

Thanks for the minute for Scientific Americans' 60-Second Science, I’m Cynthia Graber.