Narrator Of all the mutations that lead to human life, the most important is also one of the earliest – the jump from simple single-celled life to complex, multicellular life.
Chris McKay It’s hard to imagine that without multicellularity, intelligence is possible. You’ve gotta have a big enough organism so that specialization is enough that some of the cells, some of the fraction of that organism, can just focus on being a brain.
Narrator The jump from simple life to complex life begins around 2.4 billion years ago, but what was the trigger for this revolutionary change?