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Change in organisms over a long time

What is evolution ?. Change in organisms over a long time. In order for evolution to occur, there must be NATURAL VARIATION present. James Hutton Charles Lyell. Hutton and Lyell were geologists who stated the Earth was MILLIONS of years old, not thousands.

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Change in organisms over a long time

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  1. What is evolution? Change in organisms over a long time

  2. In order for evolution to occur, there must be NATURALVARIATION present.

  3. James HuttonCharles Lyell Hutton and Lyell were geologists who stated the Earth was MILLIONS of years old, not thousands.

  4. Who wrote about human population growth eventually exceeding the Earth’s resources threatening our species survival? MALTHUS

  5. Most species produce many more offspring than the resources in that area can handle. This leads to a situation called: Struggle for Existence

  6. Lamark -“Lamark missed the mark” • Species strive for perfection and complexity • “Use it, or lose it” • Acquired traits are passed on to offspring

  7. Darwin proposed the theory of NATURAL SELECTION

  8. Darwin Studied the Galapagos finches and examined how they evolved. He used the term: “Survival of the Fittest”

  9. Adaptive Radiation is the type of adaptation that new species originate from one ancestor like Darwin’s finches (Tweak the Beak) “Tweak the Beak”

  10. Darwin said that the ability of an organism to survive and reproduce in its environment is called its FITNESS!

  11. Punctuated Equilibrium - the type of evolutionary change where there is a long period of steady evolution and then a sudden event such as a volcano eruption causes change

  12. Structures from same ancestor, with same structure, but with differentfunctions are called Homologous (Homo=same) structures.

  13. Structures from different ancestors, but perform same function are called Analogous Ana=“not” structures.

  14. Vestigial organs are ones that are reduced in size and have no known function any longer.

  15. What is a fossil? Preserved remains of a living organism

  16. Who studies fossils? Paleontologists What is it called to date a fossil? Relative Dating : position of fossil in Earth’s rock layers Where are the oldest fossils found in soil? Lowest rock layers

  17. Hardy-Weinberg Equilibrium Principle Genetic Equilibrium will occur if ALL of the following 5 conditions exist (this is highly unlikely to ever happen) No mutations No emigration/immigration No natural selection Must be a large population Random mating must occur

  18. All the combined alleles in a population (species living in an area) is called the gene pool.

  19. What is the gene frequency change in a small population which is due to chanceor random event? Genetic Drift

  20. Founder Effect

  21. A species is an organism that can reproduce and produce fertile offspring. Horse Donkey Mules are not a species

  22. Why do some species evolve faster than others? Example: antibiotic resistant bacterial? (don’t respond to an antibiotic) Bacteria reproduce so rapidly they can mutate (change/evolve) faster than larger organisms that reproduce slower.

  23. Natural Selection: Nature selects the best traits for survival Changes allele frequency Artificial selection: Man selects best traits to breed.

  24. Types of Reproductive Isolation Behavioral Isolation: Traits or habits preventing reproduction (the mating song or dance of a bird) Geographical Isolation: Land separation of individuals in a species keeping them from reproducing (oceans, rivers, canyons, etc.) Temporal Isolation: Mating season is different such as winter vs. spring or April vs. October or night vs. day.

  25. Name the following graphs and describe what is happening. Stabilizing: The average (middle) individuals of a species are fittest. 1 Disruptive: The individuals at the outer ends are fittest. 2 Directional: The individuals at one end are fittest. 3

  26. What is convergent evolution? Two species that had different ancestors but due to living in the same environment, they look alike such as the dolphin and shark. What is divergent evolution? Two or more species have the same ancestor but have branched off into new species.

  27. What type of evolution is this when one species must evolve along with another for survival? Coevolution

  28. Peppered Moth & Melanism Best environment for white moths to avoid being eaten by birds Best environment for black moths to avoid being eaten by birds Environmental Pressure!

  29. Look at these embryos. Which groups came from the same ancestors? “Embryology”

  30. 3 Ways to Identify Similar Ancestor DNA Biochemistry FOSSILS EMBRYOLOGY

  31. What lead to the increase in oxygen on the Earth’s surface millions of years ago? Photosynthetic Bacteria

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