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THEORY OF EVOLUTION

THEORY OF EVOLUTION. What is evolution?. Changes that have transformed life over an immense time. The biological history of earth. ADAPTATIONS. All organisms have adaptations. What is an adaptation? An adaptation is a trait that helps an organism survive. It is inherited.

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THEORY OF EVOLUTION

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  1. THEORY OF EVOLUTION

  2. What is evolution? • Changes that have transformed life over an immense time. • The biological history of earth.

  3. ADAPTATIONS • All organisms have adaptations. • What is an adaptation? • An adaptation is a trait that helps an organism survive. • It is inherited. • You do not develop it during your lifetime. • The Strangest Defence Mechanisms In The Animal Kingdom | I Fucking Love Science

  4. Name the adaptation. • A. warning coloration • Chemical defense

  5. Walking stick Camouflage, mimicry

  6. Bee and sunflower Defense, taste

  7. Coral snake and king snake • Mimicry • Red on yellow kills a fellow. Red on black won’t hurt Jack

  8. Fish, penguins, frog • Countershading means that the back is dark and the underside is light to blend in with the bottom of the water or the sky.

  9. People?

  10. How did these organisms acquire these adaptations? In the mid 1700s, Frenchman, George Buffon, suggested the Earth might be older than a few thousand years based on his observations of fossils.

  11. 1800s Jean Baptiste Lamarck theory of acquired characteristics

  12. Theory of acquired characteristics • 1.Organisms need certain traits to survive. • 2. You develop certain body parts. Use and disuse. The more you use something, the better it gets. These are called acquired traits. • 3.Acquired traits are passed on to offspring. • Is this correct?

  13. Charles Darwin • Darwin’s father wanted him to be a doctor but after watching a child undergo surgery without anesthetic, he decided it was not for him. • Then his dad decided he should study religion. Although he was a religious person, he wanted to be a naturalist.

  14. 1841 Darwin set sail on the HMS Beagle to the Galapagos Islands off the coast of South America.

  15. 1844 Darwin wrote but did not publish his 200 page paper. • 1858 Alfred Wallace came to the same conclusion as Darwin. • 1858 Darwin published Theory on the Origin of Species.

  16. Theory of natural selection • Organisms overproduce. • Organisms must compete for survival. • Organisms vary. • Organisms with the best variations are selected to survive. • Organisms that survive reproduce and pass on desirable traits to their offspring. • What did the selecting?

  17. Darwin’s finches lived on different islands. They were similar but different, Why?

  18. How does the theory of natural selection apply to the insecticide RAID?

  19. Antibiotics and antibacterial soap

  20. Artificial selection How is natural selection different from artificial selection? In artificial selection, people select what organisms will reproduce. Darwin observed that artificial selection could produce a great deal of change in a species in a short time. He reasoned that natural selection could do the same thing.

  21. Darwin vs. Lamarck

  22. Practice • Choose an organism and a trait and by using ALL of the steps of Darwin’s natural selection explain how that organism’s trait may have developed.

  23. History of Life on Earth • The earth is about 4.6 billion years old. • Life has been on earth for 3.5 billion years.

  24. The Eras of the Earth • Precambrium A. The longest era B.Life starts C. Eukaryotes appear D.Photosynthesis begins

  25. What were the characteristics of the first organisms? • Aerobic or Anaerobic • Aquatic or Terrestrial • Prokaryote or Eukaryote • Multicellular or Unicellular • Heterotroph or Autotroph

  26. Paleozoic Era A.Many invertebrates in the water B. First vertebrates C.Life moves to land

  27. Mesozoic era • Age of reptiles • Flowering plants appear • Dinosaurs rule

  28. Cenozoic era • Age of mammals • People appear

  29. Species development • What is a species? • A group of organisms with similar traits that can produce fertile offspring. It is a distinct form of life.

  30. Reproductive Barriers • New species may develop because 2 species cannot reproduce with each other. This may be due to: • A. timing • B.Behavior • C.Habitat

  31. Geographic isolation • A barrier separates 2 groups and they develop into different species. • What are some geographic barriers.

  32. Adaptive radiation Evolution from a common ancestor. An example is Darwin’s finches.

  33. Punctuated equilibrium • A sudden change causes species to change.

  34. Industrial melanism A man made change causes a change in species.

  35. Genes and species and microevolution • What is a gene pool? A gene pool consists of all of the alleles in all the individuals in a population.

  36. Genetic drift • Change due to chance. A.Maybe some just don’t reproduce. B.Bottleneck effect Disasters reduce the size of the gene pool. C.Founder effect A small group colonizes a new area. Genes are limited to that group.

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