02 ch22evolutiondarwin2008


Published on

Published in: Technology
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • Lamarck noted how well-adapted organisms were to their environments, and believed that fossils could be understood as less perfect forms which had perished in the struggle for increasing perfection. He explained adaptation as a result of change caused by environmental pressures.
  • What did Darwin say? What evidence supports Evolution by Natural Selection? What impact did Evolution have on biology?
  • After graduation Darwin was recommended to be the conversation companion to Captain Robert FitzRoy, preparing the survey ship Beagle for a voyage around the world. FitzRoy chose Darwin because of his education, his similar social class, and similar age as the captain. Darwin noted that the plants and animals of South America were very distinct from those of Europe
  • The origin of the fauna of the Galapagos, 900 km west of the South American coast, especially puzzled Darwin. On further study after his voyage, Darwin noted that while most of the animal species on the Galapagos lived nowhere else, they resembled species living on the South American mainland. It seemed that the islands had been colonized by plants and animals from the mainland that had then diversified on the different islands
  • Show Campbell videos!!!
  • Darwin noted that the plants and animals of South America were very distinct from those of Europe. Organisms from temperate regions of South America were more similar to those from the tropics of South America than to those from temperate regions of Europe. Further, South American fossils more closely resembled modern species from that continent than those from Europe.
  • Theodosius Dobzhansky: Integrating Genetics and Evolution Theodosius Dobzhansky, a Russian geneticist who moved to the United States, provided laboratory evidence for natural selection and variation where previously there had been only field observation. Dobzhansky's work with Drosophila, or fruit flies, provided new evidence that supported Darwin's theory that natural selection, acting on genetic variation in populations, is a driving force in evolution.
  • Darwin noted that the plants and animals of South America were very distinct from those of Europe. Organisms from temperate regions of South America were more similar to those from the tropics of South America than to those from temperate regions of Europe. Further, South American fossils more closely resembled modern species from that continent than those from Europe.
  • 02 ch22evolutiondarwin2008

    1. 1. Evolution by Natural Selection QuickTime™ and aa QuickTime™ and TIFF (Uncompressed) decompressor TIFF (Uncompressed) decompressor are needed to see this picture. are needed to see this picture.AP Biology 2006-2007
    2. 2. DOCTRINEAP Biology TINTORETTO The Creation of the Animals 1550
    3. 3. But the Fossil record… OBSERVATIONAP Biology
    4. 4. mya Quaternary Molluscs Anaerobic Bacteria Jawless Fish Teleost Fish Multicellular Animals Chordates Land Plants Photosynthetic Bacteria Green Algae Seed Plants Arthropods Amphibians Mammals Birds Flowering Plants Insects Reptiles 1.5 Tertiary 63 Cretaceous Dinosaurs 135 Jurassic 180 Triassic 225 Permian 280 Carboniferous 350 Devonian 400 Silurian 430 Ordovician 500 Cambrian 570 Ediacaran 700 Precambrian, Proterozoic, & Archarozoic 4500Life’s Natural History is a record of Successions & Extinctions AP Biology
    5. 5. LaMarck  Organisms adapted to their environments by acquiring traits  change in their life time  Disuse organisms lost parts because they did not use them — like the missing eyes & digestive system of the tapeworm  Perfection with Use & Need the constant use of an organ leads that organ to increase in size — like the muscles of a blacksmith or the large ears of a night-flying bat  transmit acquired characteristics to nextAP Biology generation
    6. 6. Charles Darwin  1809-1882  British naturalist  Proposed the idea of evolution by natural selection  Collected clear evidence to support his ideasAP Biology
    7. 7. Voyage of the HMS Beagle  Invited to travel around the world  1831-1836 (22 years old!)  makes many observations of nature  main mission of the Beagle was to chart South American coastline Robert FitzroyAP Biology
    8. 8. Voyage of the HMS Beagle  Stopped in Galapagos Islands  500 miles off coast of EcuadorAP Biology
    9. 9. Succession of types Armadillos are native to the Americas, with most species found in South America. Why should extinct armadillo-like species & living armadillos be found on the same continent?Glyptodont fossils are alsounique to South America. AP Biology
    10. 10. Mylodon (left) Giant ground sloth (extinct) Modern sloth (right) “This wonderful relationship in the same continent between the dead and the living will…throw more light on the appearance of organic beings on our earth, and their disappearance from it, than any other class of facts.”AP Biology
    11. 11. Unique speciesAP Biology
    12. 12. Darwin found… birds Collected many different birds on the Galapagos Islands. Thought he found Finch? Sparrow? QuickTime™ and a Photo - JPEG decompressor very different kinds… are needed to see this picture.AP Biology Woodpecker? Warbler?
    13. 13. But Darwin found… a lot of finchesDarwin was amazed tofind out:All 14 species of birdswere finches…But there is only onespecies of finch on the LargeFinch? QuickTime™ and a Small Ground Ground Finch? Sparrow? Sparrow?mainland! Finch arePhoto - JPEG decompressor needed to see this picture. Finch How did one species of finches become so many different species now?AP Biology Woodpecker? Warbler Finch Woodpecker? Warbler? Veg. Tree Finch Warbler?
    14. 14. Tree ThinkingDescendant species Ancestral Large-seed eater? Large Ground Small-seed eater? Small Ground species QuickTime™ and a FincharePhoto - JPEG decompressor Finch needed to see this picture.AP Biology Warbler? Warbler Finch Leaf-browser? Veg. Tree Finch
    15. 15. Correlation of species to food source Seed Flower Insect eaters eaters eaters Rapid speciation: new species filling new niches, because they inherited successful adaptations.Adaptive radiation AP Biology
    16. 16. Darwin’s finches  Differences in beaks  associated with eating different foods  survival & reproduction of beneficial adaptations to foods available on islands Warbler finch Cactus finch Woodpecker finch Sharp-beaked finch Small insectivorous er Small ground tree finch Warbl finch finch Gr es Large Cactus ou ch insectivorous Medium nd fin eater tree finch ground finch fin ee Insect eaters Tr ch Seed eaters es Vegetarian Bud eater Large tree finchAP Biology ground finch
    17. 17. Darwin’s finches  Darwin’s conclusions  small populations of original South American finches landed on islands  variation in beaks enabled individuals to gather food successfully in the different environments  over many generations, the populations of finches changed anatomically & behaviorally  accumulation of advantageous traits in population  emergence of different speciesAP Biology
    18. 18. Seeing this gradation & diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species has been taken & modified for different ends.AP Biology
    19. 19. Darwin’s finches  Differences in beaks allowed some finches to…  successfully compete  successfully feed  successfully reproduce  pass successful traits onto their offspringAP Biology
    20. 20. More observations… Correlation of species to food source Whoa, Turtles, too! AP Biology
    21. 21. Many islands also show distinct local variations in tortoise morphology… …perhaps these are the first steps in the splitting of one species into several?AP Biology
    22. 22. Artificial selectionThis is not just aprocess of thepast… It is all aroundAP Biology us today
    23. 23. Selective breeding the raw genetic material (variation) is hidden thereAP Biology
    24. 24. Selective breeding Hidden variation can be exposed through selection!AP Biology
    25. 25. In historical context  Other people’s ideas paved the path for Darwin’s thinking competition: struggle for survival population growth exceeds food supply land masses change over immeasurable timeAP Biology
    26. 26. A Reluctant Revolutionary  Returned to England in 1836  wrote papers describing his collections & observations  long treatise on barnacles  draft of his theory of species formation in 1844  instructed his wife to publish this essay upon his death  reluctant to publish but didn’t want ideas to dieAP Biology with him
    27. 27. And then came the letter…. Then, in 1858, Darwin received a letter that changed everything… Alfred Russel Wallace a young naturalist working in the East Indies, had written a short paper with a new idea. He asked Darwin to evaluate his ideas and pass it along for publication.AP Biology
    28. 28. The time was ripe for the idea! To Lyell— Your words have come true with a vengeance… I never saw a more striking coincidence…so all my originality, whatever it may amount to, will be smashed.AP Biology
    29. 29. Voyage: 1831-1836 November 24, 1859, Darwin published“On the Origin of Species by Means of Natural Selection” AP Biology
    30. 30. Essence of Darwin’s ideas  Natural selection  variation exists in populations  over-production of offspring  more offspring than the environment can support  competition  for food, mates, nesting sites, escape predators  differential survival  successful traits = adaptations  differential reproduction  adaptations become moreAP Biology common in population
    31. 31. LaMarckian vs. Darwinian view  LaMarck  in reaching higher vegetation giraffes stretch their necks & transmits the acquired longer neck to offspring  Darwin   giraffes born with longer necks survive better & leave more offspring who inherit their long necksAP Biology
    32. 32. Stick your neck out… Ask Questions!AP Biology
    33. 33. Slide & Image StorageAP Biology 2006-2007
    34. 34. Life has changed over time & in turn has changed the Earth Living creatures have changed Earth’s environment, making other life possibleAP Biology
    35. 35. Evolution as Change Over Time idea accepted Evolution! before Darwin Evolution! Evolution! Evolution!AP Biology
    36. 36. Galapagos Recent volcanic origin most of animal species on the Galápagos live nowhere else in world, but they resemble species living on South American mainland.AP Biology 500 miles west of mainland
    37. 37. AP Biology
    38. 38. Coherent explanation of observations "Nothing in biology makes sense except in the light of evolution." -- Theodosius Dobzhansky March 1973 Geneticist, Columbia University (1900-1975)AP Biology 2006-2007
    39. 39. Essence of Darwin’s ideas (1) Variation exists in natural populations (2) Many more offspring are born each season than can possibly survive to maturity (3) As a result, there is a struggle for existence - competition (4) Characteristics beneficial in the struggle for existence will tend to become more common in the population, changing the average characteristics of the population - adaptations(5) Over long periods of time, and given a steady input of new variation into a population, these processes lead toAP Biologyemergence of new species the
    40. 40. Stick your neck out… Ask Questions!AP Biology
    41. 41. The Birds…  Galápagos birds  22 of the 29 species of birds on the Galapagos are endemic  found only on these islands  collected specimens of all  One particular group…  at first, he paid little attention to a series of small birds  some were woodpecker- like, some warbler-like, & some finch-likeAP Biology
    42. 42. Darwin’s finches  Darwin was amazed to find out they were all finches  14 species  but only one species on SouthLarge-seed eater? Finch? QuickTime™ and a Small-seed eater? Sparrow? American mainland Photo - JPEG decompressor are needed to see this picture.  500 miles away  all the birds had to originally come How did from mainland one species of finches become species so many different ones now?AP Biology Warbler? Warbler? Leaf-browser? Wren?