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H. C. Lim (hlim1@tigers.lsu.edu) and F. H. Sheldon, Mus. of Nat. Sci. and Dept. of Biol. Sci., Louisiana State Univ., Baton Rouge,LA 70803, USA. R. G. Moyle, Dept. of Ecol. and Evol. Biol. and Biodiv. Res. Centre, Univ. of Kansas, Lawrence, KS 66045, USA.Extensive plumage color polymorphism in the oriental dwarf kingfisher Ceyx erithaca has long intrigued ornithologists ofthe Indo Malayan region. A large proportion of birds in Sumatra, Peninsular Malaysia and Borneo have plumagesintermediate between the northerly black form and the southerly rufous form. We used molecular genetic techniques toinvestigate whether the pattern is likely caused by selection, contemporary hybridization or past introgression of genes.These data consist of DNA sequences of a mitochondrial gene (ND2) and five nuclear intronic loci. Phylogenetic analysesindicated that birds from continental southeast Asia (excluding the Thai Malay Peninsula) are well differentiated fromthose from insular southeast Asia. This genetic distinction correlates well with a fixed difference in mantle coloration.Northern birds have black mantles and are consistently dark; southern birds, though highly variable in parts of theplumage, consistently possess a rusty brown mantle. Multivariate analyses of morphometric data also support clusteringbirds in the two groups defined by mantle coloration. Coalescent analyses suggest that gene flow occurred after initialpopulation splitting. We hypothesized that the dynamic geography of the Indo Malayan Archipelago, as driven byeustatic sea-level changes related to glacial cycles, is responsible for extensive secondary contact, and gene flow, betweenthe two color forms. Such periodic contacts, after initial separation of the populations, may be equally common in othergeographically dynamic regions of the world.

The golden-mangrove whistler complex Pachycephala pectoralis/melanura is, with 66 named populations, described as the most complex avian example of geographic variation in the World. It represents a well-known example of niche differentiation where one species P. pectoralis is found on faunistically rich larger islands (and mainland) and the other P. melanura is confined to adjacent, faunistically poor islets. Except for a comparison of some Solomon Island populations, the relationships among these taxa have not been tested using molecular data. Here we combine a dense taxon sampling (22 populations of 12 named taxa distributed east of New Guinea and in Australia), with molecular data (two nuclear and two mitochondrial markers) to unravel more of the evolutionary history behind the golden whistler complex. In particular we examine relationships between Pachycephala melanura, and the very similar-looking P. citreogaster (Bismarcks Islands) and P. pectoralis (Australia). We demonstrate that a well-supported group of golden whistlers inhabit the Bismarck Islands and that several small islets in the immediate vicinity are inhabited by another monophyletic group consisting of P. melanura, mangrove golden whistler.

The pygmy kingfishers of the Old World tropics (Alcedininae) display a range of feeding behaviors, plumage types, and morphologies that have caused much taxonomic confusion in the group. We sequenced mitochondrial and nuclear genes to reconstruct a phylogenetic hypothesis for the subfamily, which was then used to examine the utility of common taxonomic characters. The phylogenetic hypothesis reveals multiple shifts between insectivory and piscivory, as well as homoplasy in bill color and plumage color. Piscivores and insectivores are interspersed across the tree, as are blue and rufous plumage types. It is apparent that reliance on these characters to delineate genera has resulted in classifications that do not describe natural groups. The sole taxonomic character examined that defines a natural division in the subfamily, toe count, is also the one generally dismissed as non-informative in the alcedinines, yet all species with a reduction in the number of toes form a clade. It is recommended that four genera be retained to describe the variation within pygmy kingfishers.

Comparison of 1017 nucleotides of mitochondrial ND2 and ND3 DNA sequences of 26 individuals of white-crowned forktail Enicurus leschenaulti from SE Asia revealed multiple evolutionary lineages within Borneo. Montane birds were genetically homogeneous across localities, but diverged by more than 4.3% from all other samples. Lowland birds formed two distinct clades, one consisting of individuals from northern Borneo, and the other including individuals from western Borneo, as well as Sumatra and Malaya. Relationships among the subspecies were not well resolved. These findings indicate another example of montane and north Bornean endemicity, support the separation of the montane and lowland species, and define areas of conservation interest.