ANTHROPOLOGY

ANTHROPOLOGY - Chapter 4 What is evolution? Darwin didn't...

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

View Full Document Right Arrow Icon
Chapter 4 What is evolution? Darwin didn’t come up with it. Darwin came up with natural selection – first good theory of evolution and why it occurs. Evolution can be referred to as descent with modification – change in allele frequencies from one generation to the next. Microevolution is what we can observe in a laboratory. Macroevolution is speciation (a fruit bat turning into an entirely different species throughout generations) The four mechanisms of evolution—define them and how they work 1. Natural Selection – The environment selects the most “fit” individuals. There must be competition for resources – if everyone can survive equally, there is nothing for the environment to select. There must be variation as well. 2. Mutation – Introduces variation. When your DNA is copying itself, it messes up a lot. Two normal sized humans having a midget child is a mutation. Must occur in sex cells for it to have evolutionary significance. 3. Gene Flow – Transmission of genes between two groups. Prevents speciation. Serves to make populations more similar. 4. Genetic Drift – Occurs in small, isolated groups. Change in allele frequencies just based on chance (without natural selection) What is the significance of variation to natural selection and evolution? If there is no variation, there is nothing for the environment to select for. We either all stay and everything stays the same, or we all die and then there is nothing! How do cultural adaptations affect evolution?
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.

This note was uploaded on 04/24/2008 for the course ANTH 103 taught by Professor Brooks during the Fall '08 term at VCU.

Page1 / 5

ANTHROPOLOGY - Chapter 4 What is evolution? Darwin didn't...

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