Africa EuropeAsia Homo erectus Modern humans: Out of Africa Mitochondrial Eve
Early human fossil from Israel, dated to 90, ,000 years ago
DNA and fossils can give different types of information
Population 1: A T G T A A C G T T A T A Population 2: A C G T A A C G T T A T A Population 3: A C G A A A C G T T A T A Population 4: A C G A A A C C T T A T A By comparing DNA changes among populations we can trace their history
Mitochondria: DNA comes from mother Offspring cell Nucleus: DNA comes from both parents Mitochondrial DNA traces the female line
150,000 65,000 40,000 50,000 Mitochondrial DNA suggests migrations out of Africa began around 65,000 years ago
The Y chromosome traces the male line Y chromosome lineages began to diverge about 60,000 years ago
Migration patterns of early humans https://genographic.nationalgeographic.com/ Y chromosome Mitochondrial DNA
By sequencing whole genomes we can see the genetic signatures of our ancestors
Genome sequences suggest two migrations into Asia An Aboriginal Australian Genome Reveals Separate Human Dispersals into Asia Morten Rasmussen, Eske Willerslev and colleagues, University of Copenhagen, Denmark Science 2011; Vol. 334 pages 94-98
150, ,000 40,000
Genome sequences suggest two migrations into Asia African European Chinese Melanesian & Aboriginal 60,000-75,000 yrs ago 1 25,000-40,000 yrs ago 2
Whom did Homo sapiens meet as they spread through Europe and Asia?
Neanderthals lived in Europe 150,000 to 30,000 years ago
Did Neanderthals and Homo sapiens interbreed? Comparison of Neanderthal (left) and modern human skulls
Fossilised bones provide a source of Neanderthal DNA Neanderthal sampling sites A draft sequence of the Neandertal genome Svante Pääbo, Richard Green and colleagues, Max Planck Institute for Evolutionary Anthropology, Germany Science 2010; Vol. 328 pages
Neanderthal Interbreeding (2%) African European Chinese Melanesian
Neanderthal African (San) Chinese Denisovan Interbreeding European Melanesian
150,000 Neanderthal Denisovan
Out of Africa, with some hybridisation Modern humans are mostly of recent African origin The contribution from Neanderthal and Denisovan hybridization is small Over 10,000 years, one mating event every years.
What does “race” mean?
60-75,000 Our recent African origin means our “racial” characteristics evolved only recently
19 th century: Human races different species?
Racial features are the result of superficial genetic changes “We are all Africans under the skin”
Blue eyes result from a single genetic change less than 10,000 years ago Percentage of Europeans with light-coloured eyes
When you look at the underlying genetic variation, we are much more similar than we appear on the surface 0.1% variation
Most human genetic variation occurs within populations AfricaAsiaEurope
Most human genetic variation occurs within populations 85-90% variation within populations 10-15% variation between populations Differences between ethnic groups are minor compared to differences among people overall
Y chromosome Mitochondrial DNA Ancestry, not race
Photo credits Slide 3: Science Photo Library Slide 4: MacMillan Publishers Slides 6, 7: Science Photo Library Slide 9: Univ. of California Museum of Paleontology (http://evolution.berkeley.edu) Slide 10: Blank map from Wikimedia Commons (Author Crates) Slide 11: Wikimedia Commons (Courtesy: National Human Genome Research Institute) Slide 12: Constructed with information from National Genographic maps and the Genographic project Slide 14: Science Photo Library Slide 15: iStockphoto Slides 18-20: Science Photo Library Slide 21: Science Magazine, American Association for the Advancement of Science Slides 22, 24: Science Photo library Slide 25: Max Planck Institute for Evolutionary Anthropology Slide 28: Science Photo Library Slide 29: TRANZ International Image Library Ltd Slide 31: Science Photo Library Slide 32, 33, 35: TRANZ International Image Library Ltd Slide 33: Wikimedia Commons (Author: NordNordWest) Slide 34: Emmanuelle Bournay, UNEP/GRID-Arendal Slide 38: Constructed with information from National Genographic maps and the Genographic project