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Museum specimens are of particular importance for investigating systematics and the biogeography as well as other aspects of the evolution of biodiversity. They are also a depository of specimens accumulated over recent historical times and often the only way to study recently extinct or rare species. Unfortunately, most museum specimens yield low-quality DNA limiting their generalized use in phylogenetic and population genetic studies. Advances in sequencing technologies now offer opportunities to analyse such material even from very small tissue. Here, we applied the Illumina technology (HiSeq) on three specimens of crowned pigeon (Goura spp.) collected in New Guinea between 1879 and 1934. A shotgun strategy allowed us to quickly and reliably assemble complete mitochondrial genomes and fragments of three single-copy gene phylogenetic markers even with low double-stranded DNA quantity (9 to 69 ng). Phylogenetic assignments of these new sequences confirmed them as Goura sequences. Therefore, our study confirms the power of using next-generation sequencing methods to investigate the evolutionary history of species for which access to fresh samples is limited but museum collections are available. These approaches are considerably increasing the value of many natural history collections for genetic investigations, particularly from biodiversity hotspots that are presently difficult to prospect. [ABSTRACT FROM AUTHOR]

Assessing the relative contributions of immigration and diversification into the buildup of species diversity is key to understanding the role of historical processes in driving biogeographical and diversification patterns in species-rich regions. Here, we investigated how colonization, in situ speciation, and extinction history may have generated the present-day distribution and diversity of Goura crowned pigeons (Columbidae), a group of large forest-dwelling pigeons comprising four recognized species that are all endemic to New Guinea. We used a comprehensive geographical and taxonomic sampling based mostly on historical museum samples, and shallow shotgun sequencing, to generate complete mitogenomes, nuclear ribosomal clusters and independent nuclear conserved DNA elements. We used these datasets independently to reconstruct molecular phylogenies. Divergence time estimates were obtained using mitochondrial data only. All analyses revealed similar genetic divisions within the genus Goura and recovered as monophyletic groups the four species currently recognized, providing support for recent taxonomic changes based on differences in plumage characters. These four species are grouped into two pairs of strongly supported sister species, which were previously not recognized as close relatives: Goura sclaterii with Goura cristata , and Goura victoria with Goura scheepmakeri . While the geographical origin of the Goura lineage remains elusive, the crown age of 5.73 Ma is consistent with present-day species diversity being the result of a recent diversification within New Guinea. Although the orogeny of New Guinea's central cordillera must have played a role in driving diversification in Goura , cross-barrier dispersal seems more likely than vicariance to explain the speciation events having led to the four current species. Our results also have important conservation implications. Future assessments of the conservation status of Goura species should consider threat levels following the taxonomic revision proposed by del Hoyo and Collar (HBW and BirdLife International illustrated checklist of the birds of the world 1: non-passerines, 2014), which we show to be fully supported by genomic data. In particular, distinguishing G. sclaterii from G. scheepmakeri seems to be particularly relevant. [ABSTRACT FROM AUTHOR]