The Story of Human Evolution Part 1: From ape-like ancestors to modern humans Part 2: What makes us human? Evolution and adaptation in modern humans We are all close relatives in our DNA Modern humans continued to evolve as they encountered new environments, new diseases and new ways of living Evolution is a gradual change in genetic makeup from one generation to the next Evolution can happen by chance, or by natural selection How natural selection works 1. Individuals are variable How natural selection works 1. Individuals are variable 2. Some variations are inherited How natural selection works 1. Individuals are variable 2. Some variations are inherited 3. Individuals with the most favourable variations have more offspring Favourable variations become more common Over time, natural selection changes organisms in response to their environment Evolution in action: Lactose tolerance Domestication of cattle drove selection for lactose tolerance Percentage of people with lactose intolerance around the world Evolution in action: Blue eyes Blue eyes result from a single genetic change less than 10,000 years ago Blue eyes are not physically advantageous, but may have been more attractive Percentage of Europeans with light-coloured eyes Are we still evolving? ? Modern life has changed but not stopped human evolution The invention of agriculture and associated dietary and lifestyle changes still drive human evolution today Gene variants involved in dietary changes and disease resistance are continuing to evolve Disease is an important driver of evolution Malaria is one of the world’s most prevalent and fatal diseases Genes that confer resistance to malaria are strongly selected for Malaria resistance genes are at high frequency in Africa Allele frequencies of malaria resistance gene FY*O P C Sabeti et al. Science 2006;312:1614-1620 The future of human evolution © Produced by Hilary Miller in association with the Allan Wilson Centre for Molecular Ecology and Evolution Thanks to Azra Moeed, Caroline Thomas, and Glenda Lewis for assistance with preparing this presentation hilary.miller10@gmail.com http://www.allanwilsoncentre.ac.nz Image credits Slides 1, 2: TRANZ INTERNATIONAL Image Library Ltd Slide 3: TRANZ INTERNATIONAL Image Library Ltd and iStockphoto Slide 4: Science Photo Library Slide 5: Wikimedia Commons Slides 6-8: Univ. of California Museum of Paleontology (http://evolution.berkeley.edu) Slide 9: Moth - Sarah Beach, stock xchng; Gecko - TRANZ INTERNATIONAL Image Library Ltd; Kakapo – Wikimedia Commons Slide 10: Wikimedia Commons Slide 11: Igor Spanholi, stock.xchng Slide 12: Wikimedia Commons Slides 13, 14: TRANZ INTERNATIONAL Image Library Ltd Slide 15: Wikimedia Commons Slide 16: Science Photo Library Slide 17: TRANZ INTERNATIONAL Image Library Ltd Slide 18: Fields – Eva Schuster, stock xchng; Barley – David Thomson, stock xchng; Crowd - TRANZ INTERNATIONAL Image Library Ltd Slide 19, 21: TRANZ INTERNATIONAL Image Library Ltd Slide 22: Science Magazine, American Association for the Advancement of Science Slides 23-25: TRANZ INTERNATIONAL Image Library Ltd