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Ecological diversification in a group of Indomalayan pitvipers ( Trimeresurus ): convergence in taxonomically important traits has implications for species identification
Author(s) -
Sanders K. L.,
Malhotra A.,
Thorpe R. S.
Publication year - 2004
Publication title -
journal of evolutionary biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.289
H-Index - 128
eISSN - 1420-9101
pISSN - 1010-061X
DOI - 10.1111/j.1420-9101.2004.00735.x
Subject(s) - biology , evolutionary biology , phylogenetic tree , ecology , taxon , phylogenetics , lineage (genetic) , systematics , zoology , taxonomy (biology) , genetics , gene
Abstract We analyse molecular and phenotypic evolution in a group of taxonomically problematic Indomalayan pitvipers, the Trimeresurus sumatranus group. Mitochondrial DNA sequencing provides a well‐resolved phylogeny, with each species representing a distinct lineage. Multivariate morphological analysis reveals a high level of phenotypic differentiation, which is congruent between the sexes but does not reflect phylogenetic history. An adaptive explanation for the observed pattern of differentiation is supported by independent contrasts analysis, which shows significant correlations between current ecology and the characters that most account for the variation between taxa, including those that are presently used to identify the species. Reduced precipitation and altitude, and increased temperature, are correlated with higher numbers of scales on the head, body and tail. It is hypothesized that scale number plays an important role in heat and water exchange by influencing the area of exposed of interstitial skin, and that colour pattern variation reflects selection pressures involving camouflage and thermoregulation. Ecological convergence in traits used for classification is found to have important implications for species identification where taxa are distributed over varying environments.