For billions of years, single-celled creatures had the planet to themselves, floating through the oceans in solitary bliss. Some microorganisms attempted multicellular arrangements, forming small ...

Almost eight years ago, Stanford University bioengineer Manu Prakash was looking for a way to watch every cell in an adult living, behaving animal in elaborate detail. He searched the catalog of life ...

Theories about how animals became multicellular are shifting as researchers find greater complexity in our single-celled ancestors. From one came many. Some 700 million years ago, a single cell gave ...