Following information taken from:
    Soule, Michael; Orians, Gordan.  Conservation Biology.  Washington: Island Press, 2001.

Isolation
    Effects within fragments
        1. environmental stochasticity (particularly large effect with extreme events, such as drought or fire)
        2. deterministic threats (for ex. habitat degradation)
        3. demographic stochasticity (affects only very small populations)
        4. loss of genetic variation

    Size and Edge Effects
        The physical changes of a forest are greatest on the edges.  Fragmentation creates more edge, so the affect of physical changes is far greater.
    There was a forest fragmentation experiment in Manaus Brazil, here are some examples of the results:
        - overall reduction in biomass
        - reduction of overstory begetation
        - increase in understory vegetation
        - fragment edges were hotter, drier, windier
            - high mortality of trees at edges
            - higher leaf-fall rate near edges
        - air temperature, litter biomass and moisture, and percentage of ground covered with twigs were correlated with the
               distance from the edges
        - beetle species composition changed both with decreasing distance from the edge, and with decreasing fragment size

Following information taken from:
    Panel of the Board on Science and Technology for International Developement.  Conserving Biodiversity.  Washington:
    National Academy Press, 1992.

    Both evolution and extinction are natural processes and have existed since life has existed.  Why are we so concerned in saving species now?  It is because habitat destruction (due to human interaction) has caused an accelerated rate of extinction.  In face, the rate of local extinctions today is 1000 to 10,000 times greater than the background rate.