We examine phylogenetic relationships
among anoles using mitochondrial DNA sequences from the NADH dehydrogenase
subunit 2 gene (ND2) and five transfer-RNA genes representing 1,455 alignable
base positions and 866 phylogenetically informative characters (parsimony
criterion). We also present 16 morphological characters for phylogenetic
analysis. Our analyses yielded poorly-supported nodes deep in the
anole tree but many well-supported nodes for more recent phylogenetic divergences.
We test the hypothesis that the major clades of anoles form a hard polytomy
and present a general statistical framework for testing hypotheses of simultaneous
branching of lineages by using molecular sequence data. Our results
suggest that rapid diversification early in the evolutionary history of
anoles explains why numerous researchers have had difficulty reconstructing
well-supported dichotomous phylogenetic trees for anoles.
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