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Ch. 19 - 3 Biogeography
  continental drift -
  dispersal -
  native species -
  exotic xpecies -

1.  Biogeography
    A.  study of where organisms live
    B.  bio = life, geo = earth, graph = description
2.  Continental drift
    A.  movement of the continents has had a great impact on the distrubition of species.
    B.  fig. 12, pg. 619
3.  Means of dispersal
    A.  caused by wind, water or living things, including humans
4.  Wind
    A.  provides a means of dispersal for seeds of plants, tiny spiders and other small light organisms
    B.  fig. 13, pg. 619
5.  Water
    A.  transports object that float
    B.  coconuts and leaves and maybe small insects
6.  Other living things
    A.  animals may eat fruit and then deposit the seeds elsewhere as waste
    B.  animals may carry sticky plant burs on their fur.
7.     Limits to dispersal
    A.  what determines the limits to a species distribution?
        1.  physical barriers
            a.  water, mtns., deserts
        2.  competition for resources
            a.  new species must compete for resources from a species already there
        3.  climate
            a.  weather can limit areas where an animal can exist.