Evolution

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.

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.

Altering a protein in the neurons that coordinate a rattlesnake’s movement made a slow slither neuron more like a speedy rattle neuron, showing one way evolution can generate new ways of moving.

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.

The visual systems of an obscure group of mollusks provide a rare natural example of path-dependent evolution, in which a critical fork in the creatures’ past determined their evolutionary futures.

The pathbreaking geneticist Cassandra Extavour pursues the secrets of multicellular life while balancing careers in both science and singing.

If evolution favors the survival of the fittest, where did the impulse to help others come from? Host Janna Levin speaks with Stephanie Preston, a neuropsychologist who studies the biology of altruism.

Why does natural selection appear to happen slowly on long timescales and quickly on short ones? A multigenerational study of four lizard species addresses biology’s “paradox of stasis.”