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biguous; the main sources of ambiguity were dispersal and the existence of
duplicated lineages combined with extinction. Apparently, the different meth-
ods are affected differentially by them; for example, BPA is more affected by
dispersal, whereas component analysis is more affected by redundant dis-
tributions (Morrone and Crisci 1995). Another comparative analysis (Biondi
1998) basically agreed with these conclusions. After these contributions,
several new methods have been described, so we lack a complete compar-
ative study.
Van Veller et al. (2000) and van Veller and Brooks (2001) compared
component compatibility, BPA, component analysis, tree reconciliation ana-
lysis, and three area statement analysis to evaluate the implementation of
assumptions 0, 1, and 2 in agreement with both requirements previously in-
dicated. In relation to the requirement that the solved sets of cladograms of
areas are successively inclusive, van Veller et al. (2000) detected violations
by component analysis, tree reconciliation analysis, and three area state-
ment analysis when there are redundant distributions or a combination of
widespread taxa and redundant distributions. Van Veller and Brooks (2001)
concluded that when vicariance and extinction are the most probable ex-
planations, BPA, component analysis, and tree reconciliation analysis would
give the same general area cladogram, but when dispersal is the most reas-
onable explanation, secondary BPA represents each dispersal event as a
falsification of the null hypothesis, whereas component analysis and tree re-
conciliation analysis remove a priori data, or duplicate lineages, and postu-
late extinctions a posteriori to avoid falsification.
Some authors (Crisci 2001; Crisci et al. 2000; Ronquist and Nylin 1990;
Sanmartín and Ronquist 2002) have considered the existence of two types
of cladistic biogeographic methods:
• Pattern-based methods: those that search for general patterns of re-
lationships between areas, without initial assumptions about particular
biogeographic processes. These methods would belong to cladistic
biogeography in the strict sense (e.g., Crisci 2001; Crisci et al. 2000).
They include component analysis, BPA, component compatibility, and
paralogy-free subtree analysis.
• Event-based methods: those that derive explicit models of particular
biogeographic processes. These methods are excluded from cladistic
biogeography by Crisci et al. (2000) and Crisci (2001). They include
tree reconciliation analysis, vicariance events analysis, and dispers-
al-vicariance analysis.
