Abstract
The 27 species of Dendroica wood-warblers represent North America's most spectacular avian adaptive radiation. Dendroica species exhibit high levels of local sympatry and differ in plumage and song, but the group contrasts with other well-known avian adaptive radiations such as the Hawaiian honeycreepers and Galapagos finches in that Dendroica species have differentiated modestly in morphometric traits related to foraging. Instead, sympatric Dendroica tend to partition resources behaviourally and they have become a widely cited example of competitive exclusion. We explored the temporal structure of Dendroica diversification via a phylogeny based on 3639 nucleotides of protein-coding mitochondrial DNA (mtDNA). The taxa sampled included 60 individuals representing 24 Dendroica species and a variety of other paruline warbler and outgroup species. Mitochondrial divergences among Dendroica species were generally large (mean pairwise interspecific distances, 10.0%) and many species were rooted in a basal polytomy. The prevalence of long terminal branches indicates that these species have evolved efficient isolating mechanisms that have prevented mtDNA introgression despite the many opportunities for hybridization resulting from local sympatry. Comparisons with a null model of random bifurcation–extinction demonstrate that cladogenesis in Dendroica has been clustered non-randomly with respect to time, with a significant burst of speciation occurring early in the history of the genus, possibly as long ago as the Late Miocene or Early Pliocene periods. Although this non-random clustering of speciation is consistent with the pattern expected of an adaptive radiation, the age of the Dendroica radiation suggests it is an 'ancient species flock' in which most extant species represent lineages that have long been evolutionarily independent.
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Selected References
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- Avise J. C., Walker D. Pleistocene phylogeographic effects on avian populations and the speciation process. Proc Biol Sci. 1998 Mar 22;265(1395):457–463. doi: 10.1098/rspb.1998.0317. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Baldwin B. G., Sanderson M. J. Age and rate of diversification of the Hawaiian silversword alliance (Compositae). Proc Natl Acad Sci U S A. 1998 Aug 4;95(16):9402–9406. doi: 10.1073/pnas.95.16.9402. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bermingham E., Rohwer S., Freeman S., Wood C. Vicariance biogeography in the Pleistocene and speciation in North American wood warblers: a test of Mengel's model. Proc Natl Acad Sci U S A. 1992 Jul 15;89(14):6624–6628. doi: 10.1073/pnas.89.14.6624. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fleischer R. C., McIntosh C. E., Tarr C. L. Evolution on a volcanic conveyor belt: using phylogeographic reconstructions and K-Ar-based ages of the Hawaiian Islands to estimate molecular evolutionary rates. Mol Ecol. 1998 Apr;7(4):533–545. doi: 10.1046/j.1365-294x.1998.00364.x. [DOI] [PubMed] [Google Scholar]
- Hasegawa M., Kishino H., Yano T. Dating of the human-ape splitting by a molecular clock of mitochondrial DNA. J Mol Evol. 1985;22(2):160–174. doi: 10.1007/BF02101694. [DOI] [PubMed] [Google Scholar]
- Hodges S. A., Arnold M. L. Columbines: a geographically widespread species flock. Proc Natl Acad Sci U S A. 1994 May 24;91(11):5129–5132. doi: 10.1073/pnas.91.11.5129. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Johnson TC, Scholz CA, Talbot MR, Kelts K, Ricketts RD, Ngobi G, Beuning K, Ssemmanda I, I, McGill JW. Late Pleistocene Desiccation of Lake Victoria and Rapid Evolution of Cichlid Fishes. Science. 1996 Aug 23;273(5278):1091–1093. doi: 10.1126/science.273.5278.1091. [DOI] [PubMed] [Google Scholar]
- Meyer A., Kocher T. D., Basasibwaki P., Wilson A. C. Monophyletic origin of Lake Victoria cichlid fishes suggested by mitochondrial DNA sequences. Nature. 1990 Oct 11;347(6293):550–553. doi: 10.1038/347550a0. [DOI] [PubMed] [Google Scholar]
- doi: 10.1098/rspb.1997.0107. [DOI] [PMC free article] [Google Scholar]
- doi: 10.1098/rspb.1998.0527. [DOI] [PMC free article] [Google Scholar]
- Sato A., O'hUigin C., Figueroa F., Grant P. R., Grant B. R., Tichy H., Klein J. Phylogeny of Darwin's finches as revealed by mtDNA sequences. Proc Natl Acad Sci U S A. 1999 Apr 27;96(9):5101–5106. doi: 10.1073/pnas.96.9.5101. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wollenberg K., Arnold J., Avise J. C. Recognizing the forest for the trees: testing temporal patterns of cladogenesis using a null model of stochastic diversification. Mol Biol Evol. 1996 Jul;13(6):833–849. doi: 10.1093/oxfordjournals.molbev.a025644. [DOI] [PubMed] [Google Scholar]