Format

Send to

Choose Destination
See comment in PubMed Commons below
Proc Biol Sci. 2007 Dec 7;274(1628):2915-23.

Exceptional among-lineage variation in diversification rates during the radiation of Australia's most diverse vertebrate clade.

Author information

1
Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853-2701, USA. dlr32@cornell.edu

Abstract

The disparity in species richness among groups of organisms is one of the most pervasive features of life on earth. A number of studies have addressed this pattern across higher taxa (e.g. 'beetles'), but we know much less about the generality and causal basis of the variation in diversity within evolutionary radiations at lower taxonomic scales. Here, we address the causes of variation in species richness among major lineages of Australia's most diverse vertebrate radiation, a clade of at least 232 species of scincid lizards. We use new mitochondrial and nuclear intron DNA sequences to test the extent of diversification rate variation in this group. We present an improved likelihood-based method for estimating per-lineage diversification rates from combined phylogenetic and taxonomic (species richness) data, and use the method in a hypothesis-testing framework to localize diversification rate shifts on phylogenetic trees. We soundly reject homogeneity of diversification rates among members of this radiation, and find evidence for a dramatic rate increase in the common ancestor of the genera Ctenotus and Lerista. Our results suggest that the evolution of traits associated with climate tolerance may have had a role in shaping patterns of diversity in this group.

PMID:
17878143
PMCID:
PMC2291154
DOI:
10.1098/rspb.2007.0924
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center