If a vaccine works, then the vaccinators might conceivably set up what's known as ring vaccinations around Ebola hot spots. In this technique, medical workers simply vaccinate everybody in a ring, miles deep, around a focus of a virus.

The annual flight of the dragonflies goes mostly unnoticed, though it is one of the great migrations of flying creatures that occur across North America.

'First Light' is nonfiction, a true story about astronomers who are looking for light coming from the edge of the universe. It tells how science is really done - and science is a lot weirder and more human than most people realize.

Green darners never attack people, but they have been seen bringing down hummingbirds. They are the Bengal tigers of the microworld.

A football player is often bigger than a basketball player - more massive, that is. The basketball player is taller and more slender. So it is with redwoods. The tallest redwoods are often slender, and so they aren't the largest ones.