BIOANTHRO EXAM REVIEW 2 - Anthropology 161. Concepts for...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Anthropology 161. Concepts for review, Midterm 2 Primate evolution Major Trends in Primate Evolution: --body size increase/’ --relative brain size increase --emphasis on vision --manual and pedal grasping --exploitation of arboreal substrates --reduction in number of teeth *early primates in the Paleocene, Plesiadapids: Paleocene Epoch: 65-55 Million years ago, Development of Protoprimates, northern latitudes, rodent-like (mostly). *Adapid and Omomyid primates in the Eocene: Eocene Epoch: 55-35 million years, 1st euprimates, warming, northern latitudes (mostly), lemur- and tarsier-like. Adapid: lemur-like Omomyid: Tarsiiforms *first monkeys from the Oligocene Oligocene Epoch: 35-25 Million years, 1st anthropoids, Old World; 1st New World monkeys; cooler. New World primate origins: --first appearance at end of Oligocene, ca. 28-26 Myr (Branisella, Bolivia) --major adaptive radiation between 20-12 Myr --most modern lineages can be traced back to the middle Miocene, ca. 16-11 Myr --intercontinental dispersal from Africa, via vegetation mat rafting? (similarity to Fayum primates such as Proteopithecus; close relationship between S. American rodents and African porcupines) --Pleistocene extinction event * fossil apes in the Miocene Miocene Epoch: 25-5 million years ago, Apes diversify; 1st Old World monkeys; hominids originate; warming Fossil Hominids – Australopithecus and Paranthropus 1. Methods of dating fossils *radiometric dating: is a technique used to date materials, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.[1] It is the principal source of information about the absolute age of rocks and other geological features, including the age of the Earth itself, and can be used to date a wide range of natural and man-made materials. Among the best-known techniques are radiocarbon dating, potassium-argon dating and uranium-lead dating. By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change. Radiometric dating is also used to date archaeological materials, including ancient artifacts.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
*relative dating: Before the advent of absolute dating in the 20th century, archaeologists and geologists were largely limited to the use of relative dating techniques. It estimates the order of prehistoric and geological events were determined by using basic stratigraphic rules, and by observing where fossil organisms lay in the geological record, stratified bands of rocks present throughout the world. Though relative dating can determine the order in which a series of events occurred, not when they occurred, it is in no way inferior to radiometric dating; in fact, relative dating by biostratigraphy is the preferred method in paleontology, and is in some respects more accurate.(Stanley, 167-9) 2. Changes associated with shift from forest to woodland / savanna
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/02/2008 for the course ANTHRBIO 161 taught by Professor Mitani during the Winter '08 term at University of Michigan.

Page1 / 9

BIOANTHRO EXAM REVIEW 2 - Anthropology 161. Concepts for...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online