1/7

1. 1/7 Welcome Back!!! • Find new seat • Pick up papers from back

4. 1/8 • Turn in: “How Fossils Are Made” • Pick up papers from back • On the “Vocabulary Etch-a-sketch” please write down: Due by Friday 1/10 • Write down Quiz and Test dates on your note packet!!!!

5. Introduction into evolution (click Picture)

6. Evolution Notes What can account for the diversity of life? I. Evolution – accounts for the diversity of life on Earth Evolution= change over time in inherited characteristics within a population process by which modern organisms have descended from ancient organisms

7. II. Theories of Evolution A. Scientific theory – a well supported testable explanation of natural phenomena ex: theory of gravity, plate techtonics NOT a guess or hunch

8. B. Jean-Baptiste Lamarck – theory of evolution – 1809 Lamarck’s theory: by selective use or disuse of organs, organisms acquired or lost traits during their lifetime; these traits could then be passed on to their offspring ex: giraffe acquired long neck by stretching for food Problem: Lamarck did not know how traits were inherited

9. You inherit blue eyes or curly hair from your parents. You acquire athletic skills or the ability to play a musical instrument

10. C. Charles Darwin – contributed more to our understanding of evolution than anyone Over time, natural selection results in changes in inherited traits of a population

11. III. Ideas that shaped Darwin’s thought on evolution A. Made observations, collected evidence – in Galapagos Islands off coast of S. America; voyaged on a boat called HMS Beagle in 1831

12. -observed similar species well suited to the environment they inhabited -traits of similar species varied noticeably among different islands of the Galapagos ex: tortoises and finches -hypothesized that animals adapted to local conditions on islands after their arrival

13. B. James Hutton and Charles Lyell – studied geology in the early 1800’s helped scientists recognize that Earth is many millions of years old; older than anyone believed • C. Thomas Malthus and human population growth – 1798 if the human population continued to grow unchecked –sooner or later there would be insufficient living space and food creating a struggle to survive

14. D. Farmers and artificial selection • -- nature provides the variation – humans select those variations they find useful • ex: cows and milk production, hogs and muscle, horses and speed

16. IV. Evolution by natural selection proposed by Darwin in On the Origin of Species, 1859 A. Struggle for existence— more offspring are produced than can survive; members of each species compete to obtain food, living space and other necessities of life

17. B. Survival of the Fittest= Natural Selection • individuals with an adaptation that makes them more “fit” for a certain environment will survive and reproduce • at a higher rate

18. adaptation -- inherited characteristic (trait) that increases an organism’s chance of survival Ex: hibernation allows body metabolism to slow so animal can survive long periods with limited food available fitness – ability of an individual to survive and reproduce in its specific environment

19. C. Descent with modification - each living species has descended, with changes, from common ancestor • -- all species (extant and extinct) • were derived from common • ancestor • -- a single tree of life links all • living things Common descent:

20. 1/9 • Get out your Evolution Notes Packets and Vocabulary Etch-a-sketch • Take out a sheet of paper to use as our warm up sheet for this unit.

21. Warm up • Describe how the following scientists influenced Darwin: • Malthus • Lamarck • Hutton and Lyell

22. V. Evidence of evolution A. Fossil record - examples of many species that have lived for a time and then became extinct

23. B. Geographical distribution of living species—looking at similar environments on different continents, animals had similar anatomies and behavior because of adaptation

24. Ex: beaver (N. America) and capybara (S. America) muskrat (N. America) and coypu (S. America) Beaver Beaver Muskrat Beaver andMuskrat Coypu Capybara Coypu andCapybara Muskrat Capybara Coypu

25. Homologous (similar or corresponding) body structures—structures that have different mature forms but develop from the same embryonic tissues; • strong evidence that all four-limbed vertebrates have descended from a common ancestor

26. Homologous Body Structures Turtle Alligator Bird Mammal Ancient lobe-finned fish

27. D. Vestigial organs—organs so reduced in size that they are just vestiges (traces) of homologous organs in other species • ex: tail bones, appendix (?), tiny leg bones in boas and pythons, wisdom teeth, hip bones in whales

28. E. Similarities in embryology—early stages (embryos) of many vertebrate animals are very similar

30. F. Components of genetic code and amino acid sequences show evolutionary relationships. a. DNA bases (ATGC) b. Converting glucose to ATP for energy.

31. Which of these is an example of evolution and why? A year or 2 of drought occurs in which a population of beetles have few plants to eat. The beetles in this population are a little smaller than the preceding generation. 90% of the beetles in a population have a gene for bright color, but 10% have a gene from brown color. Some number of generations later brown beetles comprise 70% of the population.

32. VI. EVOLUTION OF POPULATIONS (Chapter 16 – p. 392-410) Population – a group of individuals of the same speciesthat interbreed Gene pool– all the genes of all the members of a particular population (all alleles) Evolution (in genetic terms) -any change in the relative frequency of alleles in a population

33. B. Sources of genetic variation within a population • Mutations—change in the sequence of DNA; if beneficial mutation trait will increase in the population

34. 2. Recombination– genes combining in new ways during production of gametes and crossing over (meiosis)

35. 3. Gene flow – transfer of genes between populations ex:people moving from one country to another; migration of animals to another population When U.S. soldiers had children in Southeast Asia with Vietnamese women during the Vietnam War, they altered the gene pool frequencies of the Vietnamese population.

36. 1/10 • Turn in: Vocabulary Etch-a-sketch drawings • Pick up papers from the back • Read through the procedures for today’s activity • Do not touch materials on desk until given permission to do so!!!

37. 1/13 • Turn in: Peppered Moth Answer Sheet • Pick up graded work • Pick up station lab packet from the back • Take out evolution notes and keep out “How Fossils are Made”. • Reminder: Evolution Vocab Quiz Tomorrow!!!

38. 1/14 • Get prepared for the Quiz – Fill in the blank • After the quiz, get out your Notes and Station Lab – we’ll continue both after everyone’s finished with the quiz.

39. VII. Evolution as genetic change A.Evolution by Natural selection: -acts on entire populations not just individual organisms. -never acts directly on genes entire organisms survive to reproduce, or die and do not reproduce.

40. Single-gene and Polygenic Traits • 1. Single-gene: natural selection on single gene traits can lead to changes in allele frequencies and thus to evolution. • Ex: polydactyl (6 fingers) versus normal digit number (5 fingers) • 2. Polygenic Traits: effects on allele frequencies much more complex

41. a. directional selection– individuals at one end of curvehave higher fitness ex. anteaters with long tongue better for capturing ants

42. b. stabilizing selection– individuals near center of curve have higher fitness ex. Human baby weight at birth – too small low survival, but too large difficult birth

43. c. disruptive selection– upper and lower ends of curve have higher fitness ex. large and small seeds common – birds beaks are large or small

44. B. Gradualism and Punctuated Equilibrium • 1. Gradualism: change that occurs in a species at a slow steady pace • 2. Punctuated equilibrium: rapid sudden change in a species • ex: light brown and black pocket mice after volcanic eruption in New Mexico

45. C. Evolution by Genetic Drift – a random change in allele frequency Certain individuals may leave more descendants than others, and over time this can cause an allele to become common in the population. Caused by chance, not natural selection.

46. Genetic Drift:

47. 1/15 • Pick up packet from back • Get out notes and station lab (if you still have it). • No I haven’t finished grading all the quizzes. • Amino Acid Sequences is due on Friday 1/17. • We’ll work with laptops tomorrow. Make sure you remember your login info.

48. VIII. Speciation – formation of a new species • Species – group of organisms that breed with each other and produce fertile offspring in the natural environment • A. How do new species arise? • 1. Reproductive isolation = when members of two populations cannot interbreed and produce fertile offspring.

49. 2. How does reproductive isolation occur? When there are barriers to gene flow. • -behavioral isolation – courtship rituals or other behaviors are different • ex: Eastern meadow lark will not respond to Western meadowlark mating songs Western meadowlark Eastern meadowlark

50. -geographicisolation – population separated by geographic barrier like river changing course, mountains rising ex: one population of squirrels divided into 2 or more smaller populations by formation of Grand Canyon