DOC PREVIEW
UM BIOB 272 - Natural Selection Adaptation
Type Lecture Note
Pages 3

This preview shows page 1 out of 3 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 3 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 3 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

BIOB 272 1st EditionLecture 25 Outline of Last Lecture Natural Selection in the WildI. Modes of Selectiona. Directionalb. Stabilizingc. DisruptiveII. Case Study 1: Diversity in Darwin’s FinchesIII. Case Study 2: Coat Color in the Old Field Mouse: Peromyscus PolionotusIV. Case Study 3: Color Variation in KingsnakesV. Case Study 4: Gall Flies and GallsOutline of Current Lecture Natural Selection AdaptationI. Directional/stabilizing Selection in HumansII. Case Study 2: Humans and Milk- Selective Sweeps- Haplotype- Convergent and Independent EvolutionIII. Agriculture- artificial selection in crop production - Teosinte and Maize- Kernel StructureCurrent LectureThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Natural Selection AdaptationI. Directional/stabilizing selection in humans= fitness landscape- Birth mass correlated with gestation period until a certain point= creates a fitness landscape. I. Case Study 2: Humans and Milk- lactose tolerance correlates with domestication- Domesticated about 10,000 years agoo Needed increase energy foods in harsh environments- Lactose persistence= mutation- affects LCT promoter activity (gene expression)- Finding positive selection in the genome: selective sweeps- Selective Sweeps:o Positive Selection: leaves different things than neutral theory- can identify regions of genome that are different than expected with neutral theoryo Mutation= advantageous= increase frequency and then all variants follow suit= genetic hitchhiking is determined by the extent of recombination (linkage)- Haplotype: selected chromosomal sequenceo Increase frequencyo After sweep= excess of rare genetic variants with no recombination- Convergent and Independent Evolution of human lactase persistence in Africa and EuropeII. Agriculture- artificial selection in crop production - QTL studies indicate that the major phenotypic differences are due to changes at 5 genes (or linked regions)!- Many more small gene.c changes (perhaps at 1,000s of genes) influencea suite of important traits: • o starch production o Climates and types of soil o Length and number of kernels o Kernel size, shape, and color o Resistance to pests - Teosinte and Maize- Kernel Structure- Gradual increase in cob size- Kernel structure changeo Hard to soft shell of kernel- Can do a cross between maize and teosinte and get a


View Full Document

UM BIOB 272 - Natural Selection Adaptation

Type: Lecture Note
Pages: 3
Documents in this Course
Load more
Download Natural Selection Adaptation
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Natural Selection Adaptation and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Natural Selection Adaptation 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?