2. W a r m- u p Turn-in any late work. Pick up handouts Review for CH. 15.1 POP QUIZ If everyone is reviewing when the bell rings, I will give you an additional 5 minutes to study, otherwise, we will take the quiz when the bell rings PASS IT ON!

3. W a r m- u p Turn-in Natural Selection Lab and Super Organism for Late grade. Get out Evolution Notes & Picture the Vocab. Pick up handouts Write on your warm-up page 1.What is a gene? 2.What is a mutation? 3.What does isolation mean? 4.What does Equilibrium mean? Turn in for extra points on your Labs. Due 2 minutes after bell

4. W a r m- u p Turn-in Super Organism for a grade, if you did not last period. Turn-in Bird Beak Lab for a late grade. Get out Evolution Notes & Picture the Vocab. Pick up handouts AND supplies Write on your warm-up page Compare and Contrast adaptation and mutation

5. Ch. 15.2 Notes “Mechanisms of Evolution”

6. I. Who Evolves?? Individuals DO NOT evolve…Populations evolve Within a population genes and their frequencies will change over time

7. A. Vocabulary 1. Population Genetics 2. Gene pool 3. Frequency

8. 1. Population Genetics – the way genes act in plant and animal populations

9. Population Genetics **Based on the idea that evolution happens when the genes in a population change over a long period of time**

10. 2. Gene pool – all the alleles of a population’s genes 3. Frequency – how often something occurs –allelic frequency-how often an allele is seen in a population

11. Vocabulary (cont.) 4. Genetic equilibrium – allelic frequency remains the same over generations (evolution is not occurring) –The Hardy-Weinburg Principle states that for a population to remain stable, four things must happen: No natural selection__ Random mating_____ No migration____ No migration____ No mutation________

12. How do populations evolve?

13. **A disruption in a population’s equilibrium will result in evolution.** Ex:1. Genetic drift - the alteration of allelic sequences by chance events -greatly affects small populations -natural disasters such as forest fires -Galapagos Islands, -Lancaster Pennsylvania Amish community (population 12,000) *allele frequency originally 1 in 30 *now (due to small population) 1 in 14 rather than 1 in 1000 like U.S.

14. Genetic Drift

15. 2. Mutation - any change or random error in the DNA sequence -Can occur by chance; radiation, some chemicals -Can be lethal or useful -if useful will be passed on to next generation

16. II. Evolution of Species

17. A.Speciation – evolution of a new species -occurs when members of similar populations no longer interbreed to produce offspring

18. Possible Ancestral Lasan finch Amakihi Extinct mamo Crested honeycreeper Akialoa Akepa Akiapolaau Liwi Maui parrotbill Apapane Ou Grosbeak finch Palila Akikiki Niihau Kauai Oahu Lanai Molokai Maui Kahoolawe Hawaii Diversity in new environments

19. 1. Geographic isolation1. Geographic isolation – physical barrier divides a population; rivers, volcanic eruptions, earthquakes -population can no longer interbreed; two new populations form

20. Geographic isolation

21. 2. Reproductive isolation2. Reproductive isolation – formerly interbreeding organisms can no longer mate and produce fertile offspring -genetic makeup too different or behavioral reasons such as mating seasons

22. B. How fast does speciation occur? Scientists once believed that evolution occurs at a slow, steady rate, with small adaptive changes gradually accumulating over time in populations.

23. 1. Gradualism1. Gradualism – the idea that species originate through a gradual change of adaptations.

25. 2. Punctuated equilibrium2. Punctuated equilibrium – hypothesis that argues that evolution occurs quickly in rapid bursts with long periods of genetic equilibrium in between

26. III. Patterns of Evolution

27. 1. Divergent evolution 1. Divergent evolution – species that were once similar to an ancestral species diverge, or become increasingly distinct –a. Adaptive radiation – ancestral species evolves into an array of species to fit a number of diverse habitats -Darwin’s finches (pg.412)

28. 2. Convergent evolution 2. Convergent evolution – a pattern of evolution in which distantly related organisms evolve similar traits -occurs when unrelated species occupy similar environments