Extinctions: Past and Present Week 1 - Life on earth

In this video, Professor Anusaya Chinsamy-Turan discusses the history of life on earth. She begins by discussing the earliest evidence of life, which dates back to about 3.5 billion years ago. She then goes on to discuss the evolution of complex multicellular life, the Cambrian explosion, and the movement of plants and animals onto land. She also discusses some of the unanswered questions about the history of life, such as the cause of the Cambrian explosion