From ENTOMO-L listserve.

Exotic taxa less related to native species are more invasive - PNAS,
2006

Sharon Y. Strauss, Campbell O. Webb, and Nicolas Salamin. April 11,
2006. Exotic taxa less related to native species are more invasive.
Proceedings of the National Academy of Sciences 103(15): 5841–5845.

Abstract:

Some species introduced into new geographical areas from their native
ranges wreak ecological and economic havoc in their new environment.
Although many studies have searched for either species or habitat
characteristics that predict invasiveness of exotic species, the
match
between characteristics of the invader and those of members of the
existing native community may be essential to understanding
invasiveness. Here, we find that one metric, the phylogenetic
relatedness of an invader to the native community, provides a
predictive tool for invasiveness. Using a phylogenetic supertree of
all grass species in California, we show that highly invasive grass
species are, on average, significantly less related to native grasses
than are introduced but noninvasive grasses. The match between the
invader and the existing native community may explain why exotic pest
species are not uniformly noxious in all novel habitats. Relatedness
of invaders to the native biota may be one useful criterion for
prioritizing management efforts of exotic species.

PDF (large file)
http://www.pnas.org/cgi/reprint/103/15/5841.pdf

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