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- 积分
- 17983
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- 17983
- 包包
- 26159
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2014年9月25日 Nature 2 I3 z6 c" E8 E% ^. N% }5 d! [# d
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6 u' X+ a( s+ W$ s! c3 H7 l" uAccording to the theory of island biogeography, the number of species (richness) is determined by how an island's area and isolation govern rates of colonization, extinction and speciation. There is a long history of human introduction of anole lizards to Caribbean islands, hitching a ride on on crops such as pineapple and recently on ornamental plants for hotel gardens. Matt Helmus et al. take advantage of this spread of exotic species to conduct a large-scale direct test of the theory of island biogeography. Their results confirm some theoretical predictions — geographic area remains a good positive predictor of species richness, for instance. But in a world dominated by humans, geographic isolation as a negative predictor of richness has been replaced by economic isolation. For example, shipping traffic among islands is unrelated to geographic isolation and is instead linked to trade policy — illustrated by the fact that the US embargo has reduced the number of exotic anoles established on Cuba. Cover: Cuban green anole (Anolis porcatus) established in the Dominican Republic (photo: Miguel Landestoy T)
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总评分: 威望 + 20
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发表于 2014-9-28 21:46
发表于 2014-9-28 22:16
