Transcript Island biogeography

Biogeography
The study of the distribution of
species and the causes of that
distribution
Island biogeography
• An important subfield: Why do islands
have the species assemblages they do?
– That means: which species and how many?
– Why important?
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Species area relation
z
S = CA
• Species numbers tend to increase with
island area below: reptiles and amphibians in Antilles
Approx.Area
Species
Species
Index No.
mi2
(Approximate)
(Actual)
k
4
5
5
0
40
10
9
1
(400)
(20)
--
(2)
4000
40
39--40
3
40000
80
76--84
4
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small
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Deforestation in Madagascar