Why Did Ancient Humans Evolve in Africa?

Every human alive today comes from one place: East Africa. This video breaks down the genetic and fossil evidence behind that fact, and the leading science on why this one wild, unstable region might be the reason humans turned out adaptable, clever, and everywhere on Earth today. SOURCES & FURTHER READING Mitochondrial Eve and genetic evidence Cann, R.L., Stoneking, M., & Wilson, A.C. (1987). Mitochondrial DNA and human evolution. Nature, 325, 31–36. Scitable: Human Evolutionary Tree. https://www.nature.com/scitable/topic... Science News Explores: Genetics show humans likely trace back to Africa. https://www.snexplores.org/article/ge... Fossil evidence and the East African Rift PMC: A Spring Forward for Hominin Evolution in East Africa. https://pmc.ncbi.nlm.nih.gov/articles... PMC: The environmental context of human evolutionary history in Eurasia and Africa. https://pmc.ncbi.nlm.nih.gov/articles... The variability selection hypothesis Smithsonian Human Origins Program: Climate Effects on Human Evolution. https://humanorigins.si.edu/research/... Climate.gov: Climate and human evolution (interview with Richard Potts). https://www.climate.gov/news-features... LiveScience: How Humans Became Masters of the Earth. https://www.livescience.com/19832-hum... Amplifier lakes and East African climate pulses ScienceDirect: Human evolution in a variable environment: the amplifier lakes of Eastern Africa. https://www.sciencedirect.com/science... ScienceDirect: East African climate pulses and early human evolution. https://www.sciencedirect.com/science... Tool technology and the Olorgesailie research Smithsonian Magazine: To Adapt to a Changing Environment 400,000 Years Ago, Early Humans Developed New Tools and Behaviors. https://www.smithsonianmag.com/scienc... NOTES The variability selection hypothesis is influential and well-supported, but it's not the only model researchers use, and parts of the older savanna hypothesis are still discussed. Dates for genetic and fossil milestones vary somewhat between studies. 0:00 The Shared Origin of Every Human 0:38 Decoding the Genetic Evidence 2:20 What the Fossil Record Reveals 4:02 The Chaos That Built Our Brains