Zebrafish DNA contains a gene that helps to control color pattern. One particular mutation in this gene changes the fish's color from a light background with dark stripes to a golden background with no stripes. What's the big deal for us?
Researchers can experimentally manipulate a gene in another organism in order to figure out how the gene works and then look for the homologous gene in humans.
How do researchers think that natural selection has acted on this gene during recent human evolution (in the last ~ 85,000 years)?
Humans originated in Africa, where a lot of melanin (G allele) would be beneficial because it would let some UV light to penetrate allowing them to synthesize vitamin D, without giving them too much UV radiation. Those with a mutation causing them to have lighter skin would no do well in this environment. However, when humans began to migrate to colder climates, those with the mutation would have an advantage. Individuals carrying the 'a' allele had less melanin, which allowed for more UV light to penetrate their skin, and would have been able to synthesize vitamin D better.
Who is Olivia Judson, really? (You'll have to "google" her up...she is not just a NY Times writer.)
She's an evolutionary biologist who also authored Dr. Tatiana's Sex Advice to all Creation.
Briefly discuss the three reasons she gives that evolution must be taught in our schools.
-First it provides a powerful framework for investigating the world we live in.
-Second, the subject is immediately relevant here and now. The impact we're having on the planet is causing other organisms to evolve.
-Third, it concerns the development of attitude towards evidence.