1. What is Evolution? What is Evolution?

2. EVOLUTION: the process of change over time Evolution is the idea that new species develop from earlier species by accumulated changes. This is also referred to as “descent with modification”.

3. Evolution is NOT… It is NOT a fact...it's a theory: a well supported testable explanation of something that occurred in the natural world.

4. FAMOUS SCIENTISTS in Evolution: - Hutton and Lyell: Earth is many millions of years old and that the same geologic processes that changed Earth then are still occurring.

5. Lamarck's Hypothesis: Inheritance of Acquired Characteristics 1. “Acquired Characteristics”: Through use and/or non-use, those features needed for survival are developed in each individual. 2. Inheritance: Those characteristics developed (“acquired”) by individuals are passed on to their offspring, who can continue that development.

6. §Thomas Malthus- Birth rates are higher than death rates in plant and animal species. What consequences might this have on a population?

7. Darwin's Hypothesis: Natural Selection 1.Overproduction: There are more offspring produced than will survive and reproduce 2. “Survival of the fittest” (not necessarily the strongest): Those with more adaptive traits tend to survive longer and/or produce the most offspring; these are the “naturally selected”.

8. Darwin’s Travels §He sailed from England in the Beagle §Galapagos Islands near South America were most influential

9. Fitness §How well an organism is adapted to its environment §Who has a greater fitness for the North Pole? A human or a polar bear?

10. Natural selection is based on 4 facts: 1.Organisms produce more offspring than can survive. 2.There is variation among offspring. 3.There are limited resources (not enough food, water, space, etc. for everyone). 4.The organisms best fit to their environment will survive and the others will not.

11. Organisms produce more offspring than can survive. §Example: A frog can lay 200 eggs, yet not all eggs will survive to become adult frogs.

12. Results of Evolution -- Speciation!! §Speciation is the process that creates new species! §A species is a group of organisms that can naturally interbreed and produce fertile offspring. §The Liger--the offspring of a tiger and a lion. §Tigers and lions are still considered separate species, because although they can produce offspring, the offspring is not fertile.

13. Evidence of Evolution -- Fossils!! §Fossils are preserved remnants or impressions left by an organism that lived in the past. §Usually, the deeper down the fossil is, the older it is.

14. Evidence of Evolution -- Embryology! §It is believed that all vertebrates evolved from a common ancestor. The genetic information that guides their development is nearly the same. §That's why scientists can learn about human development by studying other organisms-- including zebrafish.

15. Evidence of Evolution -- Anatomical/Physiological Similarities §Notice how there are similar bones and similar structures in humans, birds and whales! l Can you tell which is the bird and which is the whale?

16. Analogous Structures §Serve the same function but are anatomically different. Serve as evidence that the organisms evolved independently

17. Vestigial Organs organ that serves no useful function over generations, they reduce in size

18. Adaptations! Inherited characteristic that increase an organism’s chance of survival §Why are most animals in the artic white? l So they blend in with the snow and avoid being seen! §Why do sharks have such sharp teeth? l It allows them to catch their prey! §Why do elephants have such big ears? l To let heat escape their bodies so they can l stay cool!

19. Extinction! §Extinction occurs when there are no members of a species left alive.

20. BIG HONKIN’ TICKET OUT 1. What do these pictures represent?

21. 2. What is a vestigial structure? 3. How do vestigial structures support the theory of evolution? 4. Give an example of a vestigial structure. ANSWERS ONLY!!!

22. 5. How do fossils serve as evidence of evolution? 6. What can we learn about evolution by looking at amino acid sequences (DNA)?

23. Ticket Out 7. Copy the table below and fill in. DefinitionExamples Homologous structures Analogous structures Vestigial structures

24. 8. FIRST WORD E- V- O- L- U- T- I- O- N-

25. H/Pre-AP Homework: Evaluate the theory of evolution Strengths Weaknesses Use your notes and Ch 15 to help you. You should also look at outside resources (internet, encyclopedia, etc)