Revista Chilena de Historia Natural 80 (4): 509-520, 2007
COMMENTARY
Towards an evolutionary biogeography
The proliferation of methods in the last decades has led some authors to question
whether biogeography is a coherent discipline. Biotas are complex mosaics due to dispersal (expansion of distributions) and vicariance
(fragmentation of distributions), having complex, reticulate histories, which necessarily need to be studied through the integration of
different methodologies. An evolutionary biogeographical analysis may involve five steps: (1) recognition of biotic components (sets of
spatio-temporally integrated taxa due to common history), through panbiogeography and methods used to identify areas of endemism;
(2) contrastation of the biotic components and identification of the vicariant events that fragmented them, through cladistics
biogeography and comparative phylogeography; (3) establishment of a hierarchic arrangement of thecomponents in a biogeographic
system of realms, regions, dominions, provinces and districts; (4) identification of cenocrons (sets of taxa with similar origins and
ages), dated using intraspecific phylogeography, molecular clocks and fossils; and (5) formulation of a geobiotic scenario, that explains
the evolution of the biotic components and cenocrons, integrating geological and tectonical information.
Key words:
evolution, cladistics,
panbiogeography, phylogeography, fossils
