1. Processes of Macroevolution: Mammalian/Primate Evolutionary History
Chapter 7
Processes of Macroevolution: Mammalian/Primate Evolutionary History

2. Chapter Outline The Human Place in the Organic World
Principles of Classification
Definition of Species
Vertebrate Evolutionary History: A Brief Summary

3. Chapter Outline Mammalian Evolution Major Mammalian Groups
Early Primate Evolution
Miocene Fossil Hominoids
Processes of Macroevolution

4. The Human Place in the Organic World
Classification groups life forms into categories showing evolutionary relationships.
Example - human classification
Kingdom: Animalia
Subkingdom: Metazoan
Phyla: Chordata
Subphyla: Vertebrata
Class: Mammalia

5. Taxonomic Concepts
Homologies - structures shared through descent from a common ancestor.
Analogies - structures used for the same function that developed independently and are not the result of common descent.
Homoplasy - the process by which similarities can develop in different groups of organisms.

6. Cladistic Taxonomy
Groups species according to shared derived characteristics:
Primitive traits reflect the ancestral condition.
Shared derived characteristics are shared traits that weren’t present before the group's appearance.

7. Approaches to the Definition of Species
Biological Species Concept
Species are defined by reproductive isolation. Only members of the same species can interbreed
Recognition Species Concept
Key aspect is the ability individuals have to identify members of their own species for mating purposes.
Ecological Species Concept
A species is a group of organisms exploiting a single niche. Natural selection separates species from one another.

8. Geological Time Scale ERA PERIOD Began m.y.a. EPOCH CENOZOIC Tertiary
1.8
Holocene
Pleistocene
0.01
Quaternary 65
Pliocene
Miocene
Oligocene
Eocene
Paleocene 5 23 34 55

9. Geological Time Scale ERA PERIOD (Began m.y.a.) MESOZOIC Cretaceous
136
Jurassic
190
Triassic
225
PALEOZOIC
Permian
Carboniferous
Devonian
Silurian
Ordovician
Cambrian
280
345
395
430
500
570

10. Geological Eras Paleozoic Mesozoic Cenozoic
The first vertebrates appeared 500 m.m.y.a.
Mesozoic
Reptiles were dominant land vertebrates.
Placental mammals appeared 70 m.Y.A.
Cenozoic
Divided into two periods: Tertiary and Quaternary and 7 epochs: Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene and Holocene.

11. Mammalian Evolution The Cenozoic era is known as the Age of Mammals.
After dinosaurs became extinct, mammals underwent adaptive radiation, resulting in rapid expansion and diversification.
The neocortex, which controls higher brain functions, comprised the majority of brain volume, resulting in greater ability to learn.

12. Major Mammalian Groups
Monotremes
Primitive, egg laying mammals
Marsupials
Infants complete development in an eternal pouch
Placental
Longer gestation allows the central nervous system to develop more completely

13. Early Primate Evolution
Primate origins began in the placental mammal radiation 65 m.y.a.
The earliest undoubted primates appear in the Eocene epoch.
Most of our knowledge of primate Oligocene evolution comes from a site in Egypt, the Fayum.

14. Fayum Forms: Possible Roots of Anthropoid Evolution
Apidium
Small, primate that may lie near or before the evolutionary divergence of Old and New World anthropoids.
Aegyptopithecus
Largest of the Fayum primates with a small brain, large snout, and none of the traits of Old World monkeys or the hominoids.

15. Miocene Fossil Hominoids
Marked by a spectacular hominoid radiation and could be called “the golden age of hominoids”.
Grouped geographically:
African forms (23-14 m.y.a.)
European forms (13-11 m.y.a.)
Asian forms (16-7 m.y.a.)

16. Genus and Species Species is the most precise taxonomic level.
Genus is a group of species more closely related to each other than to species from another genus.
Members of the same genus share derived characteristics not seen in other genera.