Cells stay together
The first organisms bigger than a single cell
See it on the timeline →In depth
Grypania spiralis from the Negaunee Formation in Michigan consists of spiral ribbons up to ten centimetres long, interpreted as an early multicellular alga. The interpretation is not uncontested. Multicellularity has arisen independently at least 25 times in the history of life — in animals, plants, fungi, brown algae and even bacteria — suggesting the transition is not especially hard. What is hard is *differentiation*: cells with identical DNA becoming distinct tissue types. That takes another billion years.
For children
For over two billion years all life was single cells. Then some cells began sticking together after dividing instead of swimming off. That let them start dividing up the work — and that is the beginning of everything from fungi to blue whales.
Connects to
Part of Terra Saga — the story of Earth on a timeline. terrasaga.org