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Number of species vs body mass

  1. Sep 15, 2009 #1
    # of species vs body mass

    Here are some graphs:


    It's obvious why the number of species that have smaller body sizes are greater in number.
    However, once we get into organisms with mass smaller than 100g, it seems to decrease. Why? One would assume it'd keep increasing, no?
    Furthermore, would the trend continue for microbials?

    Edit: Thanks DaveC, links have been fixed
    Last edited: Sep 16, 2009
  2. jcsd
  3. Sep 16, 2009 #2


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    Re: # of species vs body mass

    There may be a problem with missing species. Most microbes are impossible to culture in lab (or at least we haven't figured out how to yet), so there are likely a great number of undiscovered microbial species.
  4. Sep 16, 2009 #3
    Re: # of species vs body mass

    The graph is for animals, not microbes, so I can't imagine there being missing species.

    Also, with the advent of metagenomics, not being able to culture microbes is not a problem to get a distribution of species in an environment.
    Last edited: Sep 16, 2009
  5. Sep 16, 2009 #4

    Andy Resnick

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    Re: # of species vs body mass

    I couldn't see the graphs... does it mention the wide range of the size of dogs?
  6. Sep 16, 2009 #5


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    Re: # of species vs body mass

    Uh, that's DaveC426913. I hate nicknames... :tongue2:
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