Several factors have been proposed as drivers of species diversification in the Neotropics, including environmental heterogeneity, the development of drainage systems and historical changes in forest distribution due to climatic oscillations. Here, we investigate which drivers contributed to the evolutionary history and current patterns of diversity of a polymorphic songbird (
To investigate the cryptic diversity and diversification timing in the putatively low‐dispersal Amazonian leaf‐litter lizard
Central Amazonia, Brazil.
Squamata; Gymnophthalmidae;
We sequenced two mitochondrial and two nuclear markers in 157 individuals. Phylogeographic structure and the occurrence of independent evolving lineages where explored through phylogenetic and coalescent analyses. A species tree and divergence dates of lineages were inferred with *BEAST, employing multiple DNA substitution rates. The potential genetic impacts of geographical distance among localities, the environment and the position of localities in relation to main rivers were tested by redundancy analysis (RDA).
We detected 11 independently evolving and largely divergent intraspecific lineages. Lineage distribution patterns are complex and do not match any conspicuous barrier to gene flow, except for the Amazon River. Most lineages appear to have originated in the lower Miocene and Pliocene, in disagreement with the Pleistocene refuge hypothesis. IBD, IBE and rivers appear to have acted in concert establishing and maintaining genetic structure. However, when controlling for other explanatory variables, IBD explains significantly more variation than rivers, IBE or historical factors.
Our results strongly suggest that
- NSF-PAR ID:
- 10457675
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Biogeography
- Volume:
- 47
- Issue:
- 2
- ISSN:
- 0305-0270
- Page Range / eLocation ID:
- p. 501-515
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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