Ecological diversification in a group of Indomalayan pitvipers (Trimeresurus): convergence in taxonomically important traits has implications for species identification.
J Evol Biol
; 17(4): 721-31, 2004 Jul.
Article
in En
| MEDLINE
| ID: mdl-15271071
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.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Phenotype
/
Phylogeny
/
Trimeresurus
/
Evolution, Molecular
/
Environment
Type of study:
Diagnostic_studies
/
Prognostic_studies
Limits:
Animals
Country/Region as subject:
Asia
Language:
En
Journal:
J Evol Biol
Journal subject:
BIOLOGIA
Year:
2004
Document type:
Article
Affiliation country:
Reino Unido