This preview shows page 1. Sign up to view the full content.
Unformatted text preview: IB35ac Class 2: Our Place in Nature This lecture is a whirlwind review of the evolution of life on Earth, mammalian evolution, and a quick overview of primate evolution up to 4 million years ago. I'll talk about how the planet has changed in terms of environment, plate tectonics, orientation of continents, contingencies (asteroids), etc. IB35 Human Biological Variation Class #2, 1 Sept 2009 Monotremata (egg-laying mammals) Multituberculata (the "lost tribe" of mammals) Marsupalia (you know these guys...) Eutheria (placental mammals) Mammals Primate Evolution in 80 minutes (~1.1 million years per minute) Topics for today: ->Earth formed 4.6bya ->Prokaryotes (no nucleus) formed 3.8bya ->Eukaryotes (nucleus) formed 2.1bya ->Metazoa (animals) formed 542mya ->Mammals formed 256mya ->65mya: Asteroid hit the Earth; Dinosaurs died; Mammals radiated Hadrocodium ->First mammal species found ->Found in China ->Lived 195mya MAMMAL CHARACTERISTICS: Homeothermy: Warm-blooded; body temperature remains constant regardless of ambient temperature Heterodontism: Possess different kinds of teeth: Incisors, Canines, Premolars, Molars Lactation: Secretion of milk from mammary glands Internal gestation: Gestation occurs in womb as o...
View Full Document
This note was uploaded on 01/19/2011 for the course IB 35AC taught by Professor Hlusko during the Spring '08 term at Berkeley.
- Spring '08