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areas, with biotas comprising species of different ages derived from different
sources. Finally, the absence of particular clades in particular areas is more
parsimoniously explained as a lack of participation in that particular expan-
sion episode by a particular clade rather than dispersal with extinction.
Phylogeography
Advances in molecular biology in the late twentieth century allowed the de-
velopment of phylogeography, whose aim is to analyze the geographic dis-
tribution of genealogical lineages (Avise 2000; Avise et al. 1987). This ap-
proach has been designed explicitly to combine the power of molecular ge-
netic methods and analyses (Riddle and Hafner 2004).
Despite the potential conceptual links between phylogeography and
biogeography, some panbiogeographers (Heads 2005b) and cladistic
biogeographers (Ebach and Humphries 2002; Humphries 2000; Parenti
2007) have criticized it. Ebach and Humphries (2002), Nelson and Ladiges
(2003), and Heads (2005a, 2005b) held that phylogeography has reinvented
dispersal biogeography. Heads (2005b:679) noted, “Unfortunately, the vast
majority of molecular results are interpreted using dispersalist theory and
dubious clock calibrations.” Parenti (2007:62) stated,
Application of these techniques to systematics and biogeography
has been, on the one hand, invigorating, as it has generated many
novel hypotheses of phylogenetic relationships, yet at the sametime,
detrimental, as it has revived untestable hypotheses of centers of
origin, recognition of ancestors, and dismissal of the importance of
Earth history at all levels, not just plate tectonics, in biogeography.
I concur with Riddle and Hafner (2004) that a synthesis that uses the
reciprocal strengths of intraspecific phylogeography and cladistic biogeo-
graphy represents an interesting prospect for evolutionary biogeography.
Conclusions
Evolutionary biogeography represents a research tradition in the sense of
Laudan (1977), namely, a family of theories related by shared goals and
methods. Its origin may be traced to the nineteenth century, when Buffon's
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