As part of their Ph.D. thesis work, Burke graduate students Chris Filardi and Catherine Smith spearheaded several research trips to the Solomon Islands archipelago, where they worked with local naturalists to collect and document birds from a number of islands. Among the birds they collected were several species from a family known as "white-eyes" (Zosteropidae) – a group of ca. 100 species spread across most of the Old World tropics, and named for the characteristic eye-ring of white feathers found in most species.
Recently, Chris and Cath worked with Rob Moyle and Jared Diamond to sequence DNA from 42 white-eye species, and constructed an evolutionary history for this family. By combining DNA sequence information with what is known about the ages of islands inhabited by different white-eye species, the researchers could "date" their evolutionary tree, and estimate how rapidly species diversification was occurring. What they found was surprising: the widespread genus Zosterops, with ca. 80 species encompassing most of the family, appears to be forming species at a rate of 2-3 new species per lineage every million years — far faster than any other group of birds studied to date. This explosive speciation within a relatively short time (ca. 2 million years), and across vast geographic distances is unprecedented: no other vertebrate lineage with such a wide distribution appears to be speciating so rapidly. Why do white-eye lineages form species at such a relatively fast rate? The authors suggest that a suite of factors - including short generation times, sociality, and dispersal behavior - may make white-eyes particularly "great speciators."
Tissues from 7 species collected in the Solomon Islands, including UWBM 63177 Zosterops metcalfi from Choiseul Island; UWBM 69808 Zosterops rennellianus, and UWBM 58818 Woodfordia superciliosa, both from Rennell Island; UWBM 66034, Z. stresemanni from Malaita, UWBM 76258 and 76356, different subspecies of Z. rendovae from Rendova Island; and UWBM 76278 Z. kulambangarae from Kohingo Island.
Moyle, R. G., C. E. Filardi, C. E. Smith, and J. Diamond. 2009. Explosive Pleistocene diversification and hemispheric expansion of a "great speciator". Proceedings of the National Academy of Sciences, 106:1863-1868.
Other publications about bird speciation in the Solomon Islands:
Filardi, C. E. and C. E. Smith. 2008. Social selection and geographic variation in two monarch flycatchers from the Solomon Islands. Condor110(1).
Cleere, N., A. W. Kratter, D. W. Steadman, M. J. Braun, C. J. Huddleston, C. E. Filardi, and G. U. Y. Dutson. 2007. A new genus of frogmouth (Podargidae) from the Solomon Islands results from a taxonomic review ofPodargus ocellatus inexpectatus Hartert 1901. Ibis, 149:271-286.