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About this unit

Evidence collected during the five-year voyage of the _HMS Beagle_ led to Charles Darwin’s revolutionary theory that all species, including humans, adapt to different environments and change over time through the process of natural selection. Since a Neanderthal skullcap was discovered in 1856, thousands more fossils have helped paleoanthropologists piece together the story of our ancient ancestors, from early hominins who lived almost seven million years ago to modern _Homo sapiens_, who evolved 200,000 to 150,000 years ago. In the 1990s, geneticists joined the effort, using DNA to shed light on how modern humans are related to one another and what makes our species unique. More recently, evolutionary thinking has been helping scientists understand—and interfere with—the spread of infectious diseases. These videos and essays cover the evidence for human evolution and how understanding evolutionary biology benefits human health and wellbeing.