Multimedia

A single genetic change and some clever geometry show how single-celled organisms can band together to form cooperative multicellular entities.

A newly discovered class of microbe could help to resolve one of the biggest and most controversial mysteries in evolution — how simple microbes transformed into the complex cells that produced animals, plants and fungi.

Explore the deepest mysteries at the frontier of fundamental physics, and the most promising ideas put forth to solve them.

Solve this variation of Thomas Kirkman’s famous 1850 puzzle by arranging girls in walking groups. And think fast — the clock is ticking.

Physicists are beginning to unravel the mysteries of ultrahigh-energy cosmic rays, particles accelerated by the most powerful forces in the universe.

The largest evolutionary tree ever compiled leads researchers to conclude that chance mutation — not natural selection — drives the development of new species.

Imagine the fabric of space-time peeled back layer by layer.

A conversation with the mathematical physicist Freeman Dyson on quantum electrodynamics, climate change and his latest pet project.