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Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 22 Origins of Human Species Most modern scientists agree: Most modern scientists agree: First appeared in Africa First appeared in Africa About 5 to 7 million years ago About 5 to 7 million years ago Ape ancestors Ape ancestors Evolution produced first humanlike creatures Evolution produced first humanlike creatures

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 33 Darwin and Evolution Evolution: process of progressive change Evolution: process of progressive change Human evolution Human evolution Popularized by English biologist Charles Darwin Popularized by English biologist Charles Darwin Concept of natural selection Concept of natural selection The Origin of Species (1859) The Origin of Species (1859) The Descent of Man (humans) The Descent of Man (humans)

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 44 Concepts in Darwinian Evolution Darwin not the first Darwin not the first Aristotle, Lamarck, Linnaeus Aristotle, Lamarck, Linnaeus Natural selection Natural selection Some characteristics more favorable for survival Some characteristics more favorable for survival Survival of the fittest Survival of the fittest Mutation: random genetic changes Mutation: random genetic changes

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 55 Mutation May be neutral, beneficial or fatal May be neutral, beneficial or fatal Beneficial mutations make evolution possible Beneficial mutations make evolution possible Over time, changes in species occur Over time, changes in species occur Random or accidental Random or accidental Increased by chemical/radiation exposure Increased by chemical/radiation exposure On genetic level, involves changes in alleles On genetic level, involves changes in alleles

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 66 Genetic Engineering DNA structure discovered in 1953 DNA structure discovered in 1953 Gene splicing makes gene manipulation possible (1970s) Gene splicing makes gene manipulation possible (1970s) Genetic engineering: rearranging genetic materials to make new life forms Genetic engineering: rearranging genetic materials to make new life forms Human Genome Project Human Genome Project Proteomics Proteomics Cloning Cloning

Sociobiology A combination of sociological and biological reflections that theorize a genetic basic for human behavior. A combination of sociological and biological reflections that theorize a genetic basic for human behavior. Edward O. Wilson, Harvard entomologist, is a leader in sociobiology. Edward O. Wilson, Harvard entomologist, is a leader in sociobiology. Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 7

88 Punctuated Equilibrium vs. Gradual Change Darwin Darwin Gradual change Gradual change Natural selection process Natural selection process Microevolution Microevolution Eldredge and Gould Eldredge and Gould Long periods of stability, followed by sudden changes Long periods of stability, followed by sudden changes “Stop and go” process “Stop and go” process Macroevolution Macroevolution

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 99 Theories of Evolution

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 10 The Evolution of Human Beings: Science, Faith, and Controversy Scopes Trial (1925) Scopes Trial (1925) Teaching evolution in public schools Teaching evolution in public schools Laws against teaching evolution not repealed until 1960s Laws against teaching evolution not repealed until 1960s Scientific creationism Scientific creationism Belief, not science-based Belief, not science-based All life forms created spontaneously All life forms created spontaneously Political pressure to include in texts, schools Political pressure to include in texts, schools Not endorsed by scientists Not endorsed by scientists Intelligent design theory Intelligent design theory

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 11 Timeline of Human Evolution One-celled organisms (billions of years ago) One-celled organisms (billions of years ago) Primates (65 to 70 million years ago) Primates (65 to 70 million years ago) Apelike species (22 to 38 million years ago) Apelike species (22 to 38 million years ago) Hominids (6 to 10 million years ago) Hominids (6 to 10 million years ago) Homo sapiens (reasoning man, MODERN) Homo sapiens (reasoning man, MODERN) Homo habilis (man with tool-making ability, EXTINCT) Homo habilis (man with tool-making ability, EXTINCT) Homo erectus (upright man, EXTINCT) Homo erectus (upright man, EXTINCT)

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 12 Lines of Descent

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 13 Apes and Humans Similarities Family life Family life Care for young Care for young Emotions Emotions Social, cooperative Social, cooperative Problem solving Problem solvingDifferences Brain size Brain size Brain complexity Brain complexity Normal posture Normal posture Use of symbols Use of symbols Abstract thought Abstract thought

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 14 Emergence of Homo Sapiens Homo erectus changes into two branches: Homo erectus changes into two branches: Homo sapiens (modern humans) Homo sapiens (modern humans) Neanderthals Neanderthals Homo sapiens: larger brains, better tools Homo sapiens: larger brains, better tools Emerges about 200, ,000 years ago, possibly longer Emerges about 200, ,000 years ago, possibly longer Supplants all other hominids Supplants all other hominids Ancestors of all modern humans Ancestors of all modern humans Immediately follows Cro-Magnons? Immediately follows Cro-Magnons?

Copyright © 2014, 2011 Pearson Education, Inc. All rights reserved 15 Modern Humans Physically distinct Physically distinct Culturally sophisticated Culturally sophisticated Socially complex Socially complex New era begins as Stone Age ends New era begins as Stone Age ends Technological developments Technological developments New human interaction New human interaction