Cells

The clearest picture yet of our “last universal common ancestor” suggests it was a relatively complex organism living 4.2 billion years ago, a time long considered too harsh for life to flourish.

All modern multicellular life — all life that any of us regularly see — is made of cells with a knack for compartmentalization. Recent discoveries are revealing how the first eukaryote got its start.

Though they live only a few hours before dividing, bacteria can anticipate the approach of cold weather and prepare for it. The discovery suggests that seasonal tracking is fundamental to life.

Cells across the tree of life can swap short-lived messages encoded by RNA — missives that resemble a quick text rather than a formal memo on letterhead.

Cell membranes from comb jellies reveal a new kind of adaptation to the deep sea: curvy lipids that conform to an ideal shape under pressure.

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.

Many microbes and cells are in deep sleep, waiting for the right moment to activate. Biologists discovered a widespread protein that abruptly shuts down a cell’s activity — and turns it back on just as fast.

How do immature egg cells maintain genetic quality for decades before they mature? Scientists find unusual safeguards in this quiescent cell that may inform research into fertility.

New research has uncovered a social world of viruses full of cheating, cooperation and other intrigues, suggesting that viruses make sense only as members of a community.