HARDY-WEINBERG and GENETIC EQUILIBRIUM Turn in Flipbook! Warm-up 2/19: Make a double bubble comparing and contrasting convergent and divergent evolution. Make sure to include at a minimum: Homologous Structures Embryology Analogous Structures Biogeography Adaptive radiation Vestigial Structures Co-evolution Phenotype Artificial Selection Genotype Environment Common Ancestor HARDY-WEINBERG and GENETIC EQUILIBRIUM Ch. 16-1 pp 317-320

Variation of Traits in a Population In a population, organisms tend to show small variations of a trait Bell Curve – shows that whereas a few fish are very short and a few are very long, most are of average length. Variations are caused by mutations, genetic recombination, and random-pairing of alleles

The Gene Pool A population is the smallest level evolution can work on, changing the genetic composition of the population over time. Gene Pool = the total genetic material available in a population Adapting to new selection factors can only use existing genes found in the population Allele Frequency = the number of a certain allele in the population / the total number of all alleles The phenotype frequencies can change between generations but allele frequencies that create the phenotypes generally do not change very much between generations

The Gene Pool Gene Pool- genetic variation stored in population Each allele exists at a certain frequency - gene frequency

Hardy-Weinberg Genetic Equilibrium States that genotype frequencies remain the same from generation to generation unless acted upon by an outside influence Keep in mind this is theoretical!!! These rules generally allow us to determine the source of a population’s change Makes the following assumptions for a theoretical non-evolving population: 1) No Net Mutations – alleles remain the same 2) Individuals neither enter nor leave the population – no immigration/emigration 3) Large population – ideally infinitely large 4) Random mating 5) Selection does NOT occur – no natural or artificial selection at work

Vocab & HW Read p317-320 Do p320 #1-5 Both Due Wed. Superposition Biogeography Phylogeny/ phylogenic tree Adaptive Radiation Allele frequency Gene pool Hardy-Weinberg genetic equilibrium