Adaptive radiation is the rapid diversification of a single lineage into many species that inhabit a variety of environments or use a variety of resources and differ in traits required to exploit these. Why some lineages undergo adaptive radiation is not well-understood, but filling unoccupied ecological space appears to be a common feature. We construct a complete, dated, species-level phylogeny of the endemic Vangidae of Madagascar. This passerine bird radiation represents a classic, but poorly known, avian adaptive radiation. Our results reveal an initial rapid increase in evolutionary lineages and diversification in morphospace after colonizing Madagascar in the late Oligocene some 25 Mya. A subsequent key innovation involving unique bill morphology was associated with a second increase in diversification rates about 10 Mya. The volume of morphospace occupied by contemporary Madagascan vangas is in many aspects as large (shape variation)-or even larger (size variation)-as that of other better-known avian adaptive radiations, including the much younger Galapagos Darwin's finches and Hawaiian honeycreepers. Morphological space bears a close relationship to diet, substrate use, and foraging movements, and thus our results demonstrate the great extent of the evolutionary diversification of the Madagascan vangas.daptive radiation is the rapid diversification of a single lineage into many species that inhabit a variety of environments or niches and differ in the morphological and/or physiological traits required to exploit these environments (1-4). Well-known examples of adaptive radiations include Galapagos finches (5), Hawaiian honeycreepers (6), Hawaiian lobeliads (7), and Caribbean anoles (8). Although evolutionary biologists do not understand why some lineages undergo adaptive radiation and others do not, ecological opportunity appears to be a common feature. Opportunity might arise as a new food resource, a mass extinction of competitors and/or predators, and the colonization of new land or environments (4, 9, 10). Adaptive radiation is ultimately the outcome of divergent natural selection arising from occupation of different environments, use of different resources, or resource competition (4). The progressive filling of ecological space, and the accompanying decrease in ecological opportunity, is expected to result in a decrease in rates of diversification and morphological evolution over time (11,12).The bird family Vangidae (15 genera, 22 species) is endemic to Madagascar and considered an extraordinary example of adaptive radiation. This is due particularly to the wide range of foraging strategies as well as to the evolution of striking differences in bill morphology that have allowed vangid species to exploit diverse foraging niches (13,14). However, the evolutionary history of the group remains poorly understood. Previous systematic analyses have not included all members of the group (15)(16)(17), and these studies have not investigated morphological traits in a comparative phylogenetic framework, pre...

Aim We combined genetic sequence data and ecological niche modelling to resolve the impacts of past climatic fluctuations on the distribution, genetic diversification, and demographic dynamics of an East Asian montane bird, the green-backed tit (Parus monticolus). Location East Asia.Methods Phylogenetic analyses were carried out using four mitochondrial fragments and seven nuclear loci from 161 birds sampled from 29 localities spanning the entire geographical range of the green-backed tit. We used *beast to estimate the species tree and calculate divergence times. Extended Bayesian skyline plots were used to infer potential historical shifts in population size. We used MaxEnt to predict potential distributions during three periods: the present day, the Last Glacial Maximum and the Last Interglacial. ResultsThe mitochondrial DNA (mtDNA) gene tree showed strong support for three reciprocally monophyletic groups: a south-western clade, a central clade and a Taiwanese clade. Taiwanese and Vietnamese samples had fixed differences at several nuclear loci, but the south-western and central samples shared haplotypes at all nuclear loci. The mtDNA gene tree topology differed from the species tree topology. The species tree suggested sister relationships between Taiwanese and Vietnamese operational taxonomic units (OTUs) and between south-western and central OTUs. Diversification within the greenbacked tit was relatively recent, probably within the last 0.9 million years. Extended Bayesian skyline plots suggested rapid population expansion in the south-western and central phylogroups after the Last Interglacial, and this result was consistent with ecological niche models.Main conclusions Our results suggest that genetic diversification within the green-backed tit was affected by the later Pleistocene climate fluctuations. Ecological niche models indicated that the present-day vegetation distribution was, in many ways, more similar to that of the Last Glacial Maximum than it was to that of the Last Interglacial. Continental populations of the green-backed tit experienced unusual demographic and range expansion that is likely to have occurred during the cooling transition between the Last Interglacial and the Last Glacial Maximum. We found incongruence between the mtDNA gene tree and the species tree, which underscores the importance of using both mitochondrial and nuclear markers when estimating the evolutionary history of populations.

Babblers, family Timaliidae, have long been subject to debate on systematic position, family limits and internal taxonomy. In this study, we use five molecular regions to estimate the relationships among a large proportion of genera traditionally placed in Timaliidae. We find good support for five main clades within this radiation, and propose a new classification, dividing the babblers into the families Sylviidae and Timaliidae. Within the latter family, four subfamilies are recognized: Zosteropinae, Timaliinae, Pellorneinae and Leiothrichinae. Several taxa, previously not studied with molecular data, are phylogenetically placed within Sylviidae or Timaliidae. This is, however, not the case for the genus Pnoepyga, for which we propose the family name Pnoepygidae fam. n.