How did Multicellular Life Evolve?

At first, life on Earth was simple. Cells existed, operated, and reproduced as free-livingindividuals. But at some point, things became more complicated once unicellular organismsfound a way to group and function collectively. This transition, known as multicellularity,formed a pivotal event in the history of life on Earth. Multicellularity created the means toincrease biological complexity, which sparked an incredible diversity of organisms andstructures.

How life evolved from unicellular to multicellular organisms is still a mystery, though one thingwe do know is that this may have happened as a result of multiple independent events. To try tounderstand what could have happened, Will Ratcliff at Georgia Tech has been carrying out long-term evolution experiments in which multicellularity in yeast can spontaneously evolve andgrow. In this episode, Ratcliff talked to the Joy of Why podcast about what we know aboutmulticellularity, how his snowflake yeast model can investigate this, the surprises hisexperiments have thrown up, and how he has responded to scientists who are cynical of hisapproach.