Anthro lecture 4

Anthro lecture 4 - Anthro lecture 4 2008-10-16 Natural...

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

View Full Document Right Arrow Icon
Anthro lecture 4 15:59 Natural selection-Acts on variation present (human variation) Selection on traits o Strong= rapid evolution or extinction Depends on variation present o Weak or none= slow evolution or no change Permits variation to accumulate Variation in traits o Discrete  E.g., ABO blood group (4 phenotypes) o Continuous E.g., Height; weight; skin color Biology of skin color o 3 chemicals melanin carotene hemoglobin o multiple functions of skin all humans: o similar # of melanin producing cells o differ in rate of melanin preduction more pigment  darker skin less pigment   lighter skin UV radiation o Sun    stimulates melanin
Background image of page 1

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

View Full DocumentRight Arrow Icon
stimulates  vitamin D o need for teeth, bones, calcium absorption o UV light—synthesis of vitamin D in body Stored in fat during winter Found in some foods, added to others Variation in skin color reflects past selection pressures
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 04/07/2009 for the course ANTHRO 16254 taught by Professor Bunn,henryt.;hutchinson,sharont.;strier,karent. during the Fall '08 term at Wisconsin.

Page1 / 6

Anthro lecture 4 - Anthro lecture 4 2008-10-16 Natural...

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