GENERALISTS x SPECIALISTS

Fernando Rivadavia Lopes (ferndriv@cat.cce.usp.br)
Mon, 22 May 1995 13:24:15 -0300 (EST)


I was wondering if there was anyone out there specialized in
plant ecology and who could maybe help me out. For the past few months,
I've been discussing a question with Allen Lowrie in Australia, by
snail-mail. We're comparing how the CPs in Australia, and especially the
Drosera, are so diverse taxonomically and ecologically so specialized, while
the ones here in S.America are taxonomically much more uniform and act like
generalists, occupying a wide range of habitats over large geographical
areas. We've been trying to come to some type of conclusion as to what
ecological forces are involved. What factors in Australia are working on
the local flora (CPs and others) forcing them to diversify so much and
occupy specific soils, mostly over small geographical ranges, apparently
having very specific pollinators and (in the case of CPs) attracting
specific prey too? What gave them the extra push in Australia, which
made the Drosera evolve so much and occupy new kinds of habitats,
developing such strange structures as tubers and gemmae? What's missing
here in South America and in other parts of the world?

FERNANDO RIVADAVIA
Sao Paulo, Brazil