7 Random genetic drift - BIO 370 Kirkpatrick & Hall,...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
BIO 370 Kirkpatrick & Hall, Fall 2004 p. 1 7. Random genetic drift Random genetic drift: Changes in allele frequencies caused by the random sampling of genes The principle was not known to Darwin, but was worked out by Sewell Wright and others in the 20 th century We did an in-class simulation using playing cards to represent alleles We discovered several features of drift using: 1) a simulation in class (playing cards represented alleles in 3 populations each with 2 individuals) 2) looking at results of computer simulations 3) looking at results of an experiment using Drosophila We saw: • Drift causes evolutionary change in the absence of selection • Allele frequencies are equally likely to go up or down – there is no systematic trend • Populations that started out genetically identical became different • Genetic variation within each population was eventually lost (one allele or the other will become fixed) • Looking backward in time, one consequence of drift is that all copies of a gene
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 2

7 Random genetic drift - BIO 370 Kirkpatrick & Hall,...

This preview shows document pages 1 - 2. Sign up to view the full document.

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