Evolution: Part 1 The driver of the diversity and unity of life

Lamarck vs. Darwin Theory of Use and Disuse Acquired Transmission Increasing Complexity No Extinction Heritability Selective Pressure

Lamarck vs. Darwin Theory of Use and Disuse Acquired Transmission Increasing Complexity No Extinction Heritability Selective Pressure Theory of Natural Selection Variations Extinction (or Species Creation) Heritability Selective Pressure

_______________ do not evolve, ________________ evolve. Individuals Populations

Evidence for Evolution  Scientific observation and documentation  Homology  Fossil Record  Biogeography

Homology

Homologous Structures

Analogous Structures

Homologous Anatomical similarity, possibly different function Occurs because of evolution and inheritance Analogous Little to no anatomical similarity, similar function of structures Occurs because of convergent evolution

Vestigial Structures

Structures that were once useful to an ancestor but have lost their usefulness and have decreased in size over many generations

Biogeography 

Can evolution occur if a population is operating under the Hardy-Weinberg principle?

Hardy-Weinberg Principle  The frequency of alleles and genotypes in a population will remain constant from generation to generation.

5 Conditions for Hardy-Weinberg 1. No mutations 2. Random mating 3. No natural selection 4. Extremely large population size 5. No gene flow

Evolution: Part 2 Hardy Weinberg continued, changes in allele frequencies

Hardy Weinberg warm-up  A very large population of randomly-mating laboratory mice contains 35% white mice. White coloring is caused by the double recessive genotype, "aa". Calculate allelic and genotypic frequencies for this population.

Changes in Allelic Frequencies Genetic Drift Natural Selection Gene Flow

Genetic Drift Activity  act/drift/frame.html

Why is having a large population beneficial in terms of allele fixation?

Why is allele fixation usually detrimental evolutionarily?

Changes in Allelic Frequencies Genetic Drift Founder effect Bottleneck effect Natural Selection Gene Flow

Genetic Drift – Founder Effect  Sudden isolation of a small population from a larger population in which the smaller population establishes a new population.  Would the smaller population look the same as the larger population 500 generations down the line?

Genetic Drift – Bottleneck Effect  A severe drop in population size due to a sudden change in the environment  Does natural selection play a role in this?

Changes in Allelic Frequencies Genetic Drift Natural Selection Gene Flow

Natural Selection 

Changes in Allelic Frequencies Genetic Drift Natural Selection Directional Disruptive Stabilizing Gene Flow

DirectionalStabilizing Disruptive

What type of selection occurred in the pocket mice?