Veronique Greenwood

A popular hypothesis for how the brain clears molecular waste, which may help explain why sleep feels refreshing, is a subject of debate.

Nanotube bridge networks grow between the most abundant photosynthetic bacteria in the oceans, suggesting that the world is far more interconnected than anyone realized.

When seawater gets cold, it gets viscous. This fact could explain how single-celled ocean creatures became multicellular when the planet was frozen during “Snowball Earth,” according to experiments.

Why have bacteria never evolved complex multicellularity? A new hypothesis suggests that it could come down to how prokaryotic genomes respond to a small population size.

How did cells evolve a process to end their own lives? Recent research suggests that apoptosis, a form of programmed cell death, first arose billions of years ago in bacteria with a primitive sociality.

Paradoxically, natural selection can sometimes seem to block organisms from evolving useful adaptations. But a new study of “fitness landscapes” and antibiotic resistance in bacteria shows that life still finds a way.

For decades, Carrie Partch has led pioneering structural research on the protein clockwork that keeps time for our circadian rhythm. Is time still on her side?

Because tree seedlings don’t grow as well when close to their parents, more tree species can be packed into tropical forests.

Why did mammals, grasses and some other groups of organisms explode in diversity only after millions of years? The evolutionary biologist Andreas Wagner plumbs the secrets of those “sleeping beauties.”