The internet erupted in controversy over Felisa Wolfe-Simon and colleagues’ claim of a microbe thriving on arsenic. Nearly 15 years later, she’s pursuing new research on the boundaries of life.

Faced with a rash of shark deaths marked by brain swelling, Canadian and American scientists are trying to solve a marine mystery.

Faced with a rash of shark deaths marked by brain swelling, Canadian and American scientists are trying to solve a marine mystery.

Despite the serious risks of drinking it, a growing movement — including the potential health secretary Robert F. Kennedy Jr. — claims it has benefits. Should we take them more seriously?

“Technostuff” built in the last 100 years outweighs all the living matter on Earth.