Testing Relationships Between Biotic Components - Evolutionary Biogeography - page 205

References
Farris, J. S. 1988. Hennig86 reference. Version 1.5. Port Jefferson, N.Y.: Author.
Morrone, J. J. and M. del C. Coscarón. 1996. Distributional patterns of the American
Peiratinae (Heteroptera: Reduviidae). Zoologische Medeligen Leiden 70:1-15.
Morrone, J. J. and M. del C. Coscarón. 1998. Cladistics and biogeography of the as-
sassin bug genus Rasahus Amyot and Serville (Heteroptera: Reduviidae: Peirat-
inae). Zoologische Medeligen Leiden 72:73-87.
Nelson, G. and P. Y. Ladiges. 1995. TASS. New York: Authors.
Page, R. D. M. 1993. Component user's manual. Release 2.0. London: The Natural
History Museum.
CASE STUDY 5.6 Biogeography of Plant and Animal Taxa in the
Southern Hemisphere
The biogeographic history of the southern continents represents aclassicexample
of a vicariance scenario, with disjunct distributions explained by the sequential
breakup of Gondwana in the last 165 million years. Although most Gondwanan
taxa are presumably poor dispersers, unable to cross oceanic barriers, paleogeo-
graphic reconstructions indicate that the biogeographic history of the Southern
Hemispherecannotbeentirelyreducedtoasimplesequenceofvicarianceevents.
In addition, some molecular studies indicate that dispersal may have played a
more important role in the biotic evolution of the area than was previously as-
sumed. Sanmartín and Ronquist (2004) examined a large data set of plant and an-
imal taxa, applying tree reconciliation analysis in order to assess the relative roles
of vicariance and dispersal in the biogeographic evolution of the Southern Hemi-
sphere.
Sanmartín and Ronquist (2004) identified six basic biogeographic patterns
( figs. 5.17a - 5.17f ) to test in their analysis. The southern Gondwana pattern,
Brundin's (1966) classic pattern based on chironomid midges, which shows Africa
diverging early, followed by New Zealand, and finally by southern South America
and Australia, is congruent with the breakup of southern temperate Gondwana
during the Mesozoic-Tertiary. The tropical Gondwana pattern (Madagas-
car-Africa-northern South America) is explained by vicariance of the western part
of northern Gondwana. The plant southern pattern (New Zealand-Australia) and
the inverted southern pattern (New Zealand-southern South America) are both in-
congruent with the geological scenario and are typically explained by dispersal.
The northern Gondwana pattern, which shows the connection between the areas
that once formed northeastern tropical Gondwana, is complementary to the trop-
ical Gondwana pattern. The trans-American pattern follows earlier studies that
showed the composite nature of South America. The authors analyzed seventy-