1. What is EVOLUTION? What do you already know? K-W-L Chart

2. What questions do you have about evolution?

3. Evolution – Change in a species over time Biologists consider evolution the UNIFYING THEORY OF BIOLOGY because it helps us explain and understand the DIVERSITY of life on the planet. Define diversity: Here is a clue!

4. Consider the following observations: Lions live in Africa Tigers live in India. How are they similar? How are they different?

5. If you put a lion and a tiger together in a zoo, they can have babies. We call them ligers. How does evolution explain this?

6. "nothing in biology makes sense except in the light of evolution” ~Theodosius Dobzhansky (1900- 1975) Photo by “davemee” flickr creative commons

7. In science, theories are statements or models that have been tested and confirmed many times.

8. In science, the term "Theory" does not express doubt. ● They explain a wide variety of data and observations ● They can be used to make predictions ● They are not absolute, can be changed as new evidence is found

9. ● Why do so many different animals have the same structures, the arm bones in a human are the same bones as a flipper in a whale? ● Why is the sequence of DNA very similar in some groups of organisms but not in others? ● Why do the embryos of animals look very similar at an early stage?

10. Photo courtesy of Swamibu, Flickr Creative Commons

11. Time to take notes! Words you should know: Diversity Unifying Theory

12. Charles Darwin developed the Theory of Evolution by NATURAL SELECTION... which explained how organisms changed over time (ADAPTED) NATURAL SELECTION - process where individuals better suited to the environment survive & reproduce

13. Lamarke's Theory of Acquired Characteristics Some thought that you would gain or lose features if you overused or didn't use them !! INCORRECT !! Photo courtesy of ucumari, creative commons, flickr

14. ●Darwin was a naturalist (what we today call biologists) ●He traveled the world and made observations and sketches ●Aboard the H.M.S. Beagle, he traveled to the Galapagos Islands

15. Marine Iguana, photo courtesy of mtchm, flickr creative commons Blue-footed booby, photo courtesy of stirwise, flickr creative commons

16. Giant tortoise, Finch,

17. Checkpoint 1. Darwin traveling to which islands? 2. What was the name of his ship? 3. Name 4 species he observed on the islands. 4. He developed what theory? 5. This theory explained how organisms _______________ over _________

18. ● Each was adapted to eating a particular type of island food ● He concluded that all came from one ancestral species Cactus finch

19. 1859, Darwin publishes a book called: “The Origin of Species”

20. 1. Variation exists among individuals in a species. 2. Individuals will compete for resources 3. Competition would lead to the death of some, while others would survive 4. Individuals that had advantageous variations are more likely to survive and reproduce. Key Points to the Theory of Evolution by Natural Selection

21. This process came to be known as Natural Selection The favorable variations are called Adaptations What adaptations do tigers have? Humans? Snakes?

22. Say in a species of blob….there exists blobs of all shapes and sizes (variation) Blobs eat the little purple organisms that live underground and on the surface.

23. During a particularly hot year, food became less abundant (competition), blobs that had the ability to dig into the soil to get food had a better chance of survival. Many blobs died that year…….

24. The ones that survived mated and passed their genes to the next generation. (reproduction)

25. The next generation had move blobs with the pointed noses. That is NATURAL SELECTION. 1. Variation 2. Competition 3. Survival 4. Reproduction

26. Artificial Selection - humans selected variations they found useful and bred animals and plants for those traits.

27. Much of our agriculture (food, animals, clothing) is a result of artificial selection that has occurred over many generations. We can influence the EVOLUTION of a species

28. Checkpoint 1. What was the name of Darwin’s book? 2. The theory states that a) individuals of a species have differences, called_________ b) these individuals ________________ for resources c) some will die, others will ____________________ d) survivors will _________________________ and pass traits to offspring 3. Any trait that helps an organism survive is called an _______________________________ 4. When humans influence evolution be breeding for desired traits, it is called _______________________________

29. In 1-2 sentences, explain this image.

30. Evidence for the Theory of Evolution 1. Fossils 2. Homologous structures 3. Vestigial organs 4. DNA 5. Embryos 6. Direct Observation

31. Fossil Evidence shows….. ●similarities between extinct animals and animals that are alive ●earth’s layers, and species that lived at each time

33. Dinosaurs have always fascinated us, movies such as Jurassic Park capitalize on that fascination. How do we know what dinosaurs looked like? We create a picture based on the bones we find (fossils) and use modern reptiles to guess at their texture and skin color.

34. ● Homologous structures – these are parts of the body that are similar, but have different functions ex. The flippers of whales, and the wings of birds All forelimbs of vertebrates have the same pattern of bones Common ancestry

35. ● Vestigial Organs – these are organs or parts that seem to have no function Whales have pelvic bones that do not attach to legs Watch a short video clip on whale evolution at PB Swhale evolution at PB S

36. ● Biochemistry and DNA When comparing the DNA of one species to another, more similarities are found in species that are more closely related. Lion photo credit: ucumari Tiger photo credit: digitalART2

37. Embryological Development Embryos of different species develop in almost identical ways. Human fetus at 8 weeks

38. Direct observation of species change 1. Bacteria become resistant to antibiotics 2. Wolves were bred over many generations to become dogs (artificial selection) and then bred further to create a variety of breeds

39. Checkpoint: 1. ____________ evidence shows when organisms lived on the earth 2. Species that are closely related will have similar _______ 3. A _______________ organ is one that has no function. 4. _________________ structures look the same but have different functions, like the arm of a human and the flipper of a whale. 5. ____________ of different animals develop in the same way.

40. ● Creationism, sometimes referred to as “creation science” or “intelligent design” is the belief that organisms were placed on this earth by a divine being (God). ● It is NOT a theory because it does not follow scientific principles (theories require evidence, and must be based on NATURAL PHENOMENON) ● Finding gaps in our knowledge about evolution is a normal part of the scientific process, the existence of these “gaps” and questions does not qualify as evidence that an alternative theory must be correct

41. ● Many religious organizations do not have a problem with evolution, and it is compatible with their faith and beliefs. ● Ask your religious leaders what their thoughts are. Also see the National Center for Science Education for a list of statements from a variety of religious groups.National Center for Science Education

42. 5 Conditions of Natural Selection “ Survival of Fittest ” 1.All species have genetic variations 2.Environment presents challenges to an individual’s ability to reproduce 3.Organism tend to produce more offspring than the environment can support 4.Individuals with traits that allow them to survive → can reproduce & Pass traits on 5.Traits of best suited individuals increased over time

43. Formation of New Species Speciation – process by which new species form 1.Occurs in series of stages 2.Natural selection favors changes that ▲ reproductive success Species – group of organisms that look alike & can interbreed in nature producing fertile offspring

44. Divergence – accumulation of differences between groups Ecological races – populations of a species that differ genetically because of adaptations to different living conditions. Reproductive isolation – inability of formerly interbreeding groups to mate or produce fertile offspring Causes: 1.Geographic isolation 2.Mating season differences 3.Physical differences