LAVIN, MATT1*, MARTIN F. WOJCIECHOWSKI2, ADAM RICHMAN1, JAY ROTELLA3, MICHAEL J. SANDERSON2, and ANGELA BEYRA MATOS4. 1Department of Plant Sciences, Montana State University, Bozeman, MT 59717; 2Section of Evolution and Ecology, University of California, One Shields Avenue, Davis, CA 95616; 3Department of Ecology, Montana State University, Bozeman, MT 59717; 4Filial del Instituto de Ecologia y Sistematica, Ministerio de Ciencia Technologia y Medio Ambiente, Camaguey, C. P. 70100, Cuba. - Identifying Tertiary radiations of Fabaceae in the Greater Antilles: alternatives to cladistic vicariance analysis.
The woody genera Pictetia and Poitea represent two of
the most speciose endemic legume radiations in the Greater Antilles.
Yet component, three-area-statements, and Brooks parsimony analysis
suggest that Tertiary history has little influenced the distribution
of these genera. Either widespread taxa and composite areas mask Early
Tertiary influences or the two genera have little history on these
islands. Alternatively, nucleotide diversity, evolutionary rates, and
coalescent analyses of molecular phylogenies all suggest antiquity of
the Pictetia and Poitea radiations. These molecular
biogeographic approaches are used to identify and estimate the ages of
old endemic Tethyan radiations. These results are corroborated by
confirming a species-area disequilibrium among the legume floras for
islands of the world. Age of island biota and area of island are both
needed to most accurately predict especially endemic numbers of legume
taxa. The findings presented here combined with the legume fossil
record suggest that both Pictetia and Poitea stem from
Early Tertiary North American boreotropical ancestors. Thus, Wolfe's
hypothesis that the Greater Antilles harbor boreotropical relicts
finds support.
Key words: biogeography, boreotropics hypothesis, Fabaceae, Greater Antilles, Pictetia, Poitea