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Phylogeny and evolution of Malagasy plated lizards
Achille P Raselimanana1, Brice Noonan, K Praveen Karanth
1Département de Biologie Animale, Université d'Antananarivo, BP 906, Antananarivo (101), Madagascar. araselimanana@vahatra.mg
Molecular Phylogenetics and Evolution
|October 28, 2008
Summary
Madagascar
Area of Science:
- Herpetology
- Evolutionary Biology
- Molecular Phylogenetics
Background:
- The endemic plated lizards (Gerrhosauridae) of Madagascar represent a diverse reptile group (19 species) distributed across all island ecoregions.
- Their high diversity and wide distribution make them an ideal model for studying diversification patterns on Madagascar.
Purpose of the Study:
- To resolve the taxonomy and evolutionary relationships of Malagasy plated lizards.
- To investigate the biogeographic history and diversification patterns of this endemic group.
Main Methods:
- Generated a molecular phylogeny using mitochondrial (cob) and nuclear (NT-3, c-mos) DNA sequences (>2kb total).
- Analyzed phylogenetic relationships and estimated divergence times to infer evolutionary history.
Main Results:
- Zonosaurinae were found to be monophyletic, originating from a single Paleogene colonization event from Africa.
- Widespread mischaracterization of species based on phenotypic traits was identified, with evidence of cryptic species and phenotypic/genotypic discordance.
Conclusions:
- The study reveals a complex history of biotic diversification for Malagasy plated lizards.
- Findings provide novel insights into the biogeographic patterns and evolutionary processes shaping reptile diversity on Madagascar.
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