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Species Change Over Time

Species Change Over Time. Lamarck. Darwin. Who thought this?. There is VARIATION within a species DARWIN Organisms can make a change to themselves and pass that onto their offspring LAMARCK Change within a population, not an individual DARWIN Natural Selection DARWIN.

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Species Change Over Time

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  1. Species Change Over Time Lamarck Darwin

  2. Who thought this? • There is VARIATION within a species • DARWIN • Organisms can make a change to themselves and pass that onto their offspring • LAMARCK • Change within a population, not an individual • DARWIN • Natural Selection • DARWIN • Acquired Characteristics • LAMARCK • Organisms change over time. • BOTH • Species cannot go extinct • Lamarck • Whose idea is still believed by the scientific community today • Darwin

  3. Adaptations Over Time Chapter 12 Pages 334-341

  4. Review of Important Terms to Know • Traits-characteristics of a species that are passed from parent to offspring. • Offspring- the scientific name for “babies” of an organism

  5. Species • Species- a group similar organisms that can mate with each other and produce fertile offspring • Fertile- the ability to reproduce ~8.7 Million Species Worldwide! • Animals: 7.77 million • Fungi: 0.61 million • Plants: 0.30 million • Protozoa: 0.04 million • Chromists: 0.03 million

  6. Variation • Variation- any inherited difference between members of the same species • Ex: albino squirrel, the ability for baby turtles to swim faster, a longer neck, wider nostrils, thicker fur… Forsten’s Tortoise

  7. What Causes Variation? • SEXUAL REPRODUCTION • Variations result from permanent changes in an organism’s genes. • The permanent changes in the genes are called MUTATIONS.

  8. American Alligator with a pigment mutation

  9. Mutations…Good or Bad??? • Mutations can be either beneficial, harmful or neutral. • Some gene changes produce LARGE variations. • Ex: Albino squirrel • Some gene changes produce small variations • Ex: shape of human hairlines • “People don't realize it, but everyone has about 60 genetic mutations in their body at any given time. (Tudge, Colin)”

  10. King Cheetah Pattern Mutation • “A genetic mutation changes a spotted cheetah pattern to a striped king cheetah pattern.”

  11. Adaptation • Adaptation- a variation (or trait) that helps an organism survive & reproduce • Adaptations can be behavioral or physical.

  12. Adaptations BEHAVIORAL PHYSICAL Body structures Camouflage Shapes of beaks Fur Blubber Color or Markings Webbed-feet Body coverings • The way an organism acts or behaves • Migration • Hibernation • Communication • Mating dances

  13. 4 Principles of Natural Selection

  14. Darwin’s Theory of Natural Selection • Natural Selection- individuals that are better adapted to their environment are more likely to survive & reproduce than other members of the same species • Also known as “Survival of the Fittest”

  15. Overproduction • 1) Overproduction- producing more offspring than can survive

  16. Overproduction

  17. Competition • 2) Competition- individuals compete for food, nesting sites, territory, & other resources that affect their ability to reproduce

  18. Variation • 3) Variations- a difference between members of same species that may help it survive and reproduce • Some are born with an advantage over the others! • Ex: beak shape, eyesight, height, speed…

  19. Selection • 4) Selection- over time, the environment “selects” organisms w/ helpful traits to be parents of next generation • Ex: Just as the changing forest affected the peppered moths.

  20. . WRAP UP • Over a long period of time, natural selection can lead to the evolving of a new species. Helpful variations remain & unfavorable ones disappear

  21. Factors that Affect Natural Selection • 1) Overproduction- producing more offspring than can survive • 2) Competition- offspring compete for food & other resources • 3) Variations- a difference between members of same species that may help it survive • 4) Selection- over time, the environment “selects” organisms w/ helpful traits to be parents of next generation

  22. Do Now: Bear Trio! • In your journal answer the following questions. • What differences do you notice among the three bears? • What did Darwin call these differences? • What causes these differences among organisms?

  23. Line Graphs • Which day were the most cookies sold? • What is the title of graph? • What day were 20 cookies sold? • About how many cookies were sold on Tuesday?

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