SSS 2009-10-23（在线收听）

Some people eat to avoid being bored. Others to avoid doing something they’d rather not, like preparing a podcast. Now a report says we might eat to avoid fungi. Because warm-bloodedness, a condition that requires a lot of calories, may have evolved to keep fungal infections at bay.

There are obvious benefits to being warm blooded. Like not having to sit in the sun for a few hours just to get going in the morning. Another, less obvious plus, is the fact that we tend not to get attacked by fungi. Of the one-and-a-half million fungal species on Earth, only a few hundred are capable of infecting mammals. Compare that to a quarter of a million fungi that target plants, and 50,000 species that infect insects. So what makes us mammals relatively fungus-free? It seems to be our hot bodies.

Scientists measured how well 4,000 different fungi fared at different temperatures. They found that nearly all grow well up to about 86 degrees. Beyond that, the survivors drop by six percent for each extra degree. The study appears in the Journal of Infectious Diseases. Bottom line: if you can’t stand the fungus, get back in the kitchen.