Copyright © 2013 Pearson Education, Inc. All rights reserved. Exploring Biological Anthropology: The Essentials, 3 rd Edition CRAIG STANFORD JOHN S. ALLEN SUSAN C. ANTÓN

Copyright © 2013 Pearson Education, Inc. All rights reserved. Chapter 9 Geology and Primate Origins

Copyright © 2013 Pearson Education, Inc. All rights reserved. How to Become a Fossil Taphonomy: The study of what happens to the remains of an animal from the time of its death to the time of discovery – Burial – Geologic processes – Biological processes

Copyright © 2013 Pearson Education, Inc. All rights reserved. How to Become a Fossil (cont’d) Petrifaction Trace Fossils

Copyright © 2013 Pearson Education, Inc. All rights reserved. The Importance of Context Stratigraphy – Strata – The principle of original horizontality – The principle of superposition – The principle of cross-cutting relationships – The principal of faunal succession

Copyright © 2013 Pearson Education, Inc. All rights reserved. The Importance of Context (cont’d) The Geologic Time Scale (GTS) – The earth is ~ 4.5 billion years old – Human and primate evolution spans the last 65 million years (Cenozoic Era) – The GTS is divided into Eras, Periods, and Epochs

Copyright © 2013 Pearson Education, Inc. All rights reserved. How Old is It? Relative Dating Techniques – Lithostratigraphy – Tephrostratigraphy – Biostratigraphy – Chemical techniques within sites

Copyright © 2013 Pearson Education, Inc. All rights reserved. How Old is It? (cont’d) Calibrated Relative Dating Techniques – Geomagnetic Polarity Normal vs. reverse polarity The geomagnetic polarity time scale (GPTS) Paleomagnetism Sediments

Copyright © 2013 Pearson Education, Inc. All rights reserved. How Old is It? (cont’d) Chronometric Dating Techniques – Radiometric dating – Potassium-argon dating – Argon-argon dating – Fission track dating – Cosmogenic radionuclide techniques – Uranium Series techniques

Copyright © 2013 Pearson Education, Inc. All rights reserved. How Old is It? (cont’d) Chronometric Dating Techniques (cont’d) – Radiocarbon dating – Electron trap techniques – Thermoluminescence – Optically stimulated luminescence – Electron spin resonance

Copyright © 2013 Pearson Education, Inc. All rights reserved. The Earth in the Cenozoic Continents and Land Masses – 200 MYA the earth was divided into two major land masses Laurasia: present-day North America, Europe, and Asia Gondwanaland: Africa, South America, Antarctica, and Australia/India

Copyright © 2013 Pearson Education, Inc. All rights reserved. The Earth in the Cenozoic (cont’d) The Environment in the Cenozoic – Oxygen isotopes, temperature, and sea level – Paleosols and Loess – Vegetation – Stable Carbon Isotope Ratios in teeth and soil – Animal communities

Copyright © 2013 Pearson Education, Inc. All rights reserved. Climate Change and Early Primate Evolution Changes in the Paleocene: The origin of primates? – Plesiadapiforms Small brains Prognathic face Postorbital bar Diastema Why Primates? – Visual predation

Copyright © 2013 Pearson Education, Inc. All rights reserved. Climate Change and Early Primate Evolution (cont’d) Adapoids Continental Drift Strepsirhine-Haplorhine Split Omomyoids True Primates of the Eocene

Copyright © 2013 Pearson Education, Inc. All rights reserved. CLIMATE CHANGE AND THE ORIGIN OF MONKEYS AND APES The First Monkeys? New World Monkeys Old World Monkeys What favored the origin of anthropoids? The earliest apes

Copyright © 2013 Pearson Education, Inc. All rights reserved. Climate Change and Early Primate Evolution Evolution of brachiation Middle Miocene forests Dental evidence - a dietary shift Selection Pressures and the Divergence of Monkeys and Apes

Copyright © 2013 Pearson Education, Inc. All rights reserved. Climate Change and Early Primate Evolution (cont’d) Shift from apes to monkeys Changing environments r-selected vs. k-selected The Monkey Tale: What Happened to Primate Diversity in the Miocene?

Copyright © 2013 Pearson Education, Inc. All rights reserved. Molecular Evolution in Primates Molecular phylogeny: a tree of relatedness among taxonomic groups based on a gene or protein Molecular clock – Calibrated – Rate consistency – Relative rate test

Copyright © 2013 Pearson Education, Inc. All rights reserved. A Primate Molecular Phylogeny Morris Goodman Beta-globin Multiple calibrations Last common ancestor