In the real world, evolution doesn’t happen because we get bitten by a radioactive spider. It is usually the result of small changes in the genome that build up over time. Life on earth has evolved from simple microorganisms to become incredibly complex animals. So how did that happen?
This video explores the theory that many years ago, a cell was absorbed into another one, and because they had some things in common, they were able to come together to create a new kind of complex cell. That theory of endosymbiosis has been suggested to explain the origins of the mitochondria, for example, which are an essential part of eukaryotic cells. Learn more from the video.