Geography Reference
In-Depth Information
Construction
of
a
Geobiotic
Once we have identified the biotic components and cenocrons, we may be
able to construct a geobiotic scenario. By compiling biological data (e.g.,
means of dispersal) and nonbiological data (e.g., past continental configura-
tions) we can integrate a plausible scenario to help explain the episodes of
vicariance or biotic divergence and dispersal or biotic convergence that have
shaped the biotic evolution of the biotic components analyzed. In this chapter
I discuss some basic concepts that are considered in the construction of geo-
biotic scenarios, with a brief account of plate tectonics.
Both panbiogeographers and cladistic biogeographers have shown interest
in geology, geophysics, and plate tectonics (Cooper 1989; Craw 1988a;
Craw et al. 1999; Ebach and Humphries 2002; Grehan 2001b; Heads 1989;
Michaux 1989). Geology and biogeography have a causal relationship; they
are the independent and dependent variables, respectively (Michaux 1989).
This does not imply that geological hypotheses necessarily validate biogeo-
graphic hypotheses. Geologists may not necessarily have interpreted geolo-
gical history of the area adequately enough to justify validation. In fact, the
relationship between geology and biogeography should be based on its ca-
pacity for “reciprocal illumination” (in the sense of Hennig 1950). In order to
make this relationship more fruitful, it would be important to develop a com-
mon language that allows interconnection of the biological and geological
systems. This is because evolution in space and time of taxa and biotas is a
