|
 
- 积分
- 17983
- 威望
- 17983
- 包包
- 26159
|

2014年9月25日 Nature
8 y6 P) i7 u) a% u
. e& Q$ \, j4 ^; [2 y4 q$ H
( e! M8 n, @; M S! e# zAccording 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 But in a world dominated by humans, geographic isolation as a negative predictor of richness has been replaced by economic isolation.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)$ v' A& H8 b* ~+ P' ]+ A
: X9 W& s/ E" F C6 C" k, I
|
-
总评分: 威望 + 20
包包 + 20
查看全部评分
|