BIO 200 Lecture Notes - Lecture 31: Krakatoa, Insular Biogeography, Charismatic Megafauna
18 Dec 2018
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Document Summary
Theory of island biogeography: lesson of krakatau, island biogeography explains species distributions in new envs. Why do we care: terrestrial islands: reversing island model, real life data, protecting equilibrium, reserve design, charismatic megafauna. Krakatau- volcanic island in indonesia b/t java and sumatra. 1883 eruptions- released 20 megatons tnt; island gone with no life left. Anak krakatau built up by further volcanic eruptions- krakatau no longer lifeless. Over 50 yrs: we see 47 vertebrae with a few new birds. Robert macarthur and e. o wilson"s theory of island biogeography (for oceanic islands): explains how plants/animals distribute in new env (predicts species diversity) Immigration decreases over time: as more arrive, lower chance for new arrival to be considered novel species. Extinction inc over time: larger popn less susceptible to random extinction but very susceptible to competitive exclusion. Extinction more likely with smaller popn bc fewer resources. Equilibrium species #/s*: point at which immigration=extinction. Species # should stay constant at this point.
