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Evolution in humans?

  1. Jun 14, 2007 #1
    They have not found any major evolution is humans for nearly 30,000 years... I know it is a very slow process but 30,000 years is not enough for a little some thing to happen so we can prove that evolution is real?
  2. jcsd
  3. Jun 15, 2007 #2
    You can find a lot of evidence for evolution without investigating humans. Antibiotic resistant bacteria is one example.
  4. Jun 15, 2007 #3


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    If the average human generation is 20 years, 30,000 years is 1500 generations. Since bacteria reproduces every 20 minutes, 1500 generations is only 20 days.
  5. Jun 15, 2007 #4

    jim mcnamara

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    Staff: Mentor

    When a species has high fitness, it may not change much over long periods, if the environment does not change.
  6. Jun 15, 2007 #5
    Just in order to illustrate this point, look at sharks. They have remained basically the same for millions of years.

    If you look at adaptations prior to this period, you'll see that the human brain doubled in size in a fairly short period of time.
  7. Jun 15, 2007 #6


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    Keep in mind that for quite a lot of time, rather than the environment selecting for human fitness, humans have been modifying their environment to suit their current traits. This is going to limit the impact of typical selection processes in humans. Those adapted to cold, northern climates are not prevented from traveling and interbreeding with those adapted to hot, equatorial climates (they can just get on an air-conditioned plane and go there).
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