Biography

He graduated from Princeton University, and received a doctorate in zoology from Yale University.

He taught at Amherst College in Massachusetts and the University of Florida, and later became a research professor at Virginia's Sweet Briar College.

He was a leading authority on the monarch butterfly. He discovered that it protects itself by converting a toxic compound from its sole food source, the milkweed plant, into a chemical that sickens its predators, mainly birds.

His parents owned a nursery and rose-growing business.

I didn't realize what I was looking at. It was like a wall, turning from green to gray. It was monarch wings, folded as they roosted - the underside of their wings are grayish. So, here was this wall of butterflies, and I just couldn't believe it. For the first time in my life, I saw millions of monarch butterflies right in front of me. They were covering the trees, they were all over the boughs. They were on the trunks. They were on the limbs. They were on the bushes. They were everywhere. It is one of the most marvelous sights you can behold in the biological world. [describing his first visit to the monarch butterflies' winter home in Mexico]