Phys A L6

Phys A L6 - Physical Anthropology Lecture 6(Chapter 3 I Genetic Drift A When populations are small genetic drift may cause random changes in gene

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
10/22/2007 Physical Anthropology: Lecture 6 (Chapter 3) I. Genetic Drift A. When populations are small, genetic drift may cause random changes in gene frequencies 1. In small populations random effects due to sampling variations become important and also plays a role during genetic transmission in small populations 2. The rate of genetic drift depends on population size 3. Genetic drift cause isolated population to become genetically different from each other II. Local vs. Optimal Adaptation A. Natural Selection may lead to evolutionary disequilibrium at which the mean phenotype isn’t the best possible phenotype B. Some local adaptations are call developmental constraints C. Also constrained by laws of physics and chemistry 1. Law of mechanics predict that strengths of bones is proportional to cross- sectional areas D. What are Constraints? 1. Factors which precluded adaptation from achieving perfection or that bias evolution along certain lines 2. Genetic constraints—lack of genetic material genetic variation concentrated
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/08/2008 for the course ANTH 5 taught by Professor Gaulin during the Fall '07 term at UCSB.

Ask a homework question - tutors are online