1. Evolution in Populations Wyoming, wolf was killing livestock, legally hunted Newfoundland

2. Genetic variation in populations 2 main sources of variation (create biodiversity): o mutation – a random change of DNA in certain cells; many fail o recombination – during meiosis (forming of egg/sperm), new allele combos are given to offspring; produces a random shuffling of genes Possible source of variation: o hybridization – crossing of different species which creates new varieties (possible source)

3. natural selection trends create 4 types of distributions

4. normal distribution bell curve average is the highest extreme population is much less human height

5. directional selection nature favors one of the extremes bell curve shifts (right or left) This then becomes “normal” Ex: drug resistant bacteria (less resistance to more)

6. Shifts one direction –Ex: horses taller, wolves to dogs smaller

7. stabilizing selection the average becomes even more favored bell curve becomes tightened Ex: Gall flies in goldenrod (woodpeckers eat large larvae) (wasp larvae eat small larvae)

8. Gall Weed Wasps /Downy Woodpeckers

9. disruptive selection Both extreme phenotypes become favored by nature The average drops out could lead to a new species Ex: Lazuli bunting mating patterns (extreme blue feathers – dominate) (blue-brown mix get outcompeted) (brown feathers are left alone)

10. Sexual Selection (two types) quality control for all populations… intersexual (between genders) – females choose mates based on physical traits Ex: bird (males) - songs/colorful feathers intrasexual (within same gender) – males fight for the females; winner gets all the females

11. biodiversity is the # different species; changes when new species form or extinctions happen gene flow - alleles move from one population to another; if gene flow stops, each population will evolve separately and develop greater genetic differences because of natural selection

12. How new species form (11.5) speciation theory - two main parts (mutation, isolation) 1.genetic mutations are passed in sex cells to the next generation; increases genetic diversity (70% fail) Do not help survival Peppered Moth

13. 2.isolation – prevents gene flow; separate species evolve geographic - separated by some geographic boundary (ex: ocean/mountain/desert) temporal - different breeding season: – fall (Brown Trout) – spring (Rainbow Trout) behavioral - blue vs. red-footed boobies; different mating dances

14. speciation time frame – minimum of 50 generations – maximum of millions to billions of years

15. Patterns of Evolution (11.6) convergent evolution – different species evolve to adapt in a similar environment – analogous structures: tail fin of fish, reptile, and mammal all function the same

16. Local example of convergent evolution Mudpuppy (amphibian) Burbot (fish)

17. Divergent evolution – when closely related species evolve in different habitats to become increasingly different. Example: Homologous Structures look same/different function. Red FoxKit Fox.

18. Beneficial Relationships in evolution Coevolution: two or more species evolve in response to changes in each other. http://video.nationalgeographic.com/video/an imals/bugs-animals/ants-and- termites/ant_acaciatree/

19. Species become Extinct Background Extinctions- happen continuously but at a very low rate –roughly same as speciation. Mass Extinctions – more rare, happen on global scale –geologic events Ex: Meteor – Dinosaurs Humans causing…

20. Speciation Patterns Punctuated Equilibrium: episodes of speciation followed by long periods of no change. Adaptive Radiation: the diversification of one ancestral species into many descendants.