PDF(Pubmed)
Abstract：
Although originating from a common Gondwanan flora, the diversity and composition of the floras of Africa and South America have greatly diverged since continental breakup of Africa from South America now having much higher plant species richness. However, the phylogenetic diversity of the floras and what this tells us about their evolution remained unexplored. We show that for a given species richness and considering land surface area, topography, and present-day climate, angiosperm phylogenetic diversity in South America is higher than in Africa. This relationship holds regardless of whether all climatically matched areas or only matched areas in tropical climates are considered. Phylogenetic diversity is high relative to species richness in refugial areas in Africa and in northwestern South America, once the gateway for immigration from the north. While species richness is strongly influenced by massive plant radiations in South America, we detect a pervasive influence of historical processes on the phylogenetic diversity of both the South American and African floras.
摘要：
虽然起源于一种常见的冈瓦南植物，自从非洲大陆从南美分裂以来，非洲和南美的植物区系的多样性和组成已经大相径庭，现在植物物种丰富度更高。然而,植物区系的多样性以及这告诉我们它们的进化仍未被探索。我们证明，对于给定的物种丰富度和考虑陆地表面积，地形,和当今的气候，南美的被子植物系统发育多样性高于非洲。无论是否考虑所有气候匹配区域或仅考虑热带气候的匹配区域，这种关系都成立。相对于非洲和南美西北部的避难所地区的物种丰富度，系统发育多样性很高。曾经是北方移民的门户。虽然物种丰富度受南美大量植物辐射的强烈影响，我们发现历史过程对南美和非洲植物区系发生多样性的普遍影响。
