SSS 2010-02-19（在线收听）

When you’re looking for a table in a crowded cafeteria, you probably give wide berth to the family that sounds like it’s sharing a big dish of whooping cough. Well, not if you’re a house finch, particularly a male. Because a study in the journal Biology Letters shows that male finches actually prefer feeding near males who are visibly ill.

Finches don’t get whooping cough. But they are susceptible to infection with something called Mycoplasma gallisepticum, a bug that leaves them lethargic and sporting a bad case of conjunctivitis, otherwise known as pinkeye. The disease is quite contagious and can be passed from one finch to another while dining beak-to-beak. All the more reason, you’d think, for healthy birds to avoid sitting next to someone with crusty red peepers. Yet male house finches, when given a choice, opt to break breadcrumbs with males who are obviously under the weather.

Why risk catching a nasty infection when all you really want to catch is a quick bite? Because males infected with Mycoplasma tend to be less aggressive. So eating with the infirm means you’re more likely to wind up with seed in your beak than a beak in your eye.

——Karen  Hopkin