The African and Asian elephants and the mammoth diverged ca. 4^6 million years ago and their phylogenetic
relationship has been controversial. Morphological studies have suggested a mammoth^Asian
elephant relationship, while molecular studies have produced con£icting results. We obtained cytochrome
b sequences of up to 545 base pairs from ¢ve mammoths, 14 Asian and eight African elephants. A high
degree of polymorphism is detected within species. With a dugong sequence used as the outgroup,
parsimony and maximum-likelihood analyses support a mammoth^African elephant clade. As the
dugong is a very distant outgroup, we employ likelihood analysis to root the tree with a molecular clock,
and use bootstrap and Bayesian analyses to quantify the relative support for di¡erent topologies. The
analyses support the mammoth^African elephant relationship, although other trees cannot be rejected.
Ancestral polymorphisms may have resulted in gene trees di¡ering from the species phylogeny. Examination of morphological data, especialy from primitive fossil members, indicates that some
supposed synapomorphies between the mammoth and Asian elephant are variable, others convergent or autapomorphous. A mammoth^African elephant relationship is not excluded. Our results highlight the
need, in both morphological and molecular phylogenetics, for multiple markers and close attention to
within-taxon variation and outgroup selection.
The African and Asian elephants and the mammoth diverged ca. 4^6 million years ago and their phylogenetic
relationship has been controversial. Morphological studies have suggested a mammoth^Asian
elephant relationship, while molecular studies have produced con£icting results. We obtained cytochrome
b sequences of up to 545 base pairs from ¢ve mammoths, 14 Asian and eight African elephants. A high
degree of polymorphism is detected within species. With a dugong sequence used as the outgroup,
parsimony and maximum-likelihood analyses support a mammoth^African elephant clade. As the
dugong is a very distant outgroup, we employ likelihood analysis to root the tree with a molecular clock,
and use bootstrap and Bayesian analyses to quantify the relative support for di¡erent topologies. The
analyses support the mammoth^African elephant relationship, although other trees cannot be rejected.
Ancestral polymorphisms may have resulted in gene trees di¡ering from the species phylogeny. Examination of morphological data, especialy from primitive fossil members, indicates that some
supposed synapomorphies between the mammoth and Asian elephant are variable, others convergent or autapomorphous. A mammoth^African elephant relationship is not excluded. Our results highlight the
need, in both morphological and molecular phylogenetics, for multiple markers and close attention to
within-taxon variation and outgroup selection.
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