Jingszo !

Tracing the evolution of animals and multicellular life

Once upon a time, there were a bunch of one-celled microbes, swimming, eating, reproducing, doing all the things that a one-cell bit of life can do.

Then, some time later, there were their descendants, the early animals: multicelled creatures, still swimming, eating, reproducing, but doing it all as teams of cells.

Exactly what happened between those points is a nigh-unfathomable mystery. But that in no way stops scientists from wondering and hypothesizing and investigating how the transition, about 600 million years ago, might have gone down.

The question is an old one, but researchers have made great progress in the past two decades, thanks to the genetic sequencing of single-celled life forms that are animals’ closest kin. It turns out that the unicellular ancestors of animals, way back then, were already remarkably well-equipped to take on teamwork.