Download Biological Anthropology: The Natural History of Humankind

Exploring Biological
Anthropology:
The Essentials, 3rd 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)
True Primates of the Eocene
Adapoids
Omomyoids
Continental Drift
Strepsirhine-Haplorhine
Split
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
Selection Pressures and the Divergence of
Monkeys and Apes
Evolution of brachiation
Middle Miocene forests
Dental evidence - a dietary shift
Copyright © 2013 Pearson Education, Inc. All rights reserved.
Climate Change and Early Primate
Evolution (cont’d)
The Monkey Tale: What Happened to Primate Diversity in
the Miocene?
Shift from apes to monkeys
Changing environments
r-selected vs. k-selected
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
Copyright © 2013 Pearson Education, Inc. All rights reserved.