BIRDS - Return of the Natives: How Wild Bees Will Save Our Agricultural System

Field biologists have a strange affinity for spending countless hours in the hot sun scrutinizing tiny things. You might see a bee buzzing on a flower and think, “Oh, a bee.” A biologist, though, will want to know: Is it a nonnative, domesticated honeybee? Or is it one of 4,000 bee species native to the U.S.—maybe an ultragreen sweat bee, a metallic-sheened creature that drinks human perspiration?

http://www.scientificamerican.com/article.cfm?id=return-of-the-natives