BioLect3 - Lecture 3 Odds Ends Still on CH 22 Start CH 23...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Lecture 3 Evidence • Still on CH 22 • Start CH 23 on Wednesday Road Map: 1. Evolution after Darwin 3. Evidence of Evolution Good scientists always remain skeptical of any theory Continue to question and test scientific theories – we have much yet to learn
Background image of page 1

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

View Full DocumentRight Arrow Icon
2 Evolution through Natural Selection 1. There is variation in traits in a population (not all individuals identical) 3. Any population of a species has the potential to produce far more offspring than the environment can support Based on three observations and deductive reasoning: 2. Traits are passed on to offpsring IF IF IF Favorable traits will accumulate in the population over time Inference 2 THEN Evolution – timeline of ideas 1865: reported on plant breeding experiments Gregor Mendel Mendel’s experiments were the basis for a model of particulate inheritance Evolution – timeline of ideas 1908: Hardy-Weinberg equilibrium Quantitative model of how various forces could alter gene frequencies Evolution – timeline of ideas 1930’s: Modern synthesis genetics R.A. Fisher J.B.S. Haldane T. Dobzhansky The Genetical Theory of Evolution (1930) Mutation Genetics mathematician population genetics
Background image of page 2
3 DNA Francis Crick James Watson Sequencing of Genomes James D. Watson's Genome 2007 Mouse Genome 2002 Human Genome 2003 150 Years later! Evolution through Natural Selection 1. There is variation in traits in a population (not all individuals identical) 3. Any population of a species has the potential to produce far more offspring than the environment can support Based on three observations and deductive reasoning: 2. Traits are passed on to offpsring IF IF IF Favorable traits will accumulate in the population over time Inference 2 THEN genetic ^ inherited = changes in gene frequencies over time Evolutionary Theory Is Constantly Evolving ! 1. Darwinian evolution a steady gradual process- Gould 1992: "Punctuated Equilibrium" 2. Genetic drift, stabilizing selection, horizontal transfer, epigenetics
Background image of page 3

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

View Full DocumentRight Arrow Icon
4 Natural Selection Summary 1. Individuals that are better adapted to their environment leave more offspring 2. Advantageous heritable traits (ADAPTATIONS!) accumulate in the population over time. can also say… differential reproductive success of some individuals over others means that certain genes increase in the population while others increase The result: natural selection increases the match between organisms and their environment. What happens if the environment changes (or the
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/27/2011 for the course BIOL 112 taught by Professor Vaughn during the Spring '08 term at Texas A&M.

Page1 / 13

BioLect3 - Lecture 3 Odds Ends Still on CH 22 Start CH 23...

This preview shows document pages 1 - 5. Sign up to view the full document.

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