Tiny brainlike cell cultures called organoids offer clues about human evolution.
Sponges, one of the most ancient animal lineages, can maintain normal gene activity even as oxygen levels drop.
Expeditions in remote Amazon waterways result in identification of two previously unknown electrified fish.
Researchers find that membranes may have helped the building blocks of life come together.
Microbiologists are debating how a group of ancient microbes fits into the emergence of the first complex organisms.