Life's Little Mysteries

Here's why the nuclear bombs dropped in Japan left shadows of people on the ground and buildings.

Here's the highest temperature and humidity level that people can tolerate.

Why are common household items like baking soda and vinegar such good cleaning agents?

Here's why nuclear bomb explosions lead to a mushroom-shape cloud.

If Earth abruptly stopped spinning, what would happen to everything on it?

How does DNA know when to become active?

Higher tides, bigger earthquakes, and more frequent volcanic eruptions would plague the planet.

Particle accelerators can help scientists measure the smallest and largest particles in the universe.

Humans are slow and weak compared with bears, pumas and other large predators, but these beasts usually avoid us. Why don't these animals try to eat us more often?

Women tend to outlive men because of biological and social factors.

Atoms are the building blocks of all matter in the universe, but how many are there in the part of it we can see from Earth?

Why do humans blink so much?

New evidence shows that watermelons were first domesticated in Sudan, leading experts to think the region rivals Iraq as a cradle of agriculture.

While often strained, the U.K.-U.S. relationship got a boost when Roosevelt and Churchill became drinking buddies.

Some animals lead quiet lives, while others prefer constant chatter. Why do some animals vocalize more than others, and what are they saying?

Can animals that live in the water suffocate?

Our planet is constantly moving, racing around the sun and spinning on its axis. But how fast does it move?

Several cosmic characteristics, including the lack of an atmosphere, lend space its dark color.

Here's why "It's not the heat; it's the humidity" rings true.