New Zealand Passerines Help Clarify the Diversification of Major Songbird Lineages during the Oligocene.

Passerines are the largest avian order, and the 6,000 species comprise more than half of all extant bird species. This successful radiation probably had its origin in the Australasian region, but dating this origin has been difficult due to a scarce fossil record and poor biogeographic assumptions. Many of New Zealand's endemic passerines fall within the deeper branches of the passerine radiation, and a well resolved phylogeny for the modern New Zealand element in the deeper branches of the oscine lineage will help us understand both oscine and passerine biogeography. To this end we present complete mitochondrial genomes representing all families of New Zealand passerines in a phylogenetic framework of over 100 passerine species. Dating analyses of this robust phylogeny suggest Passeriformes originated in the early Paleocene, with the major lineages of oscines "escaping" from Australasia about 30 Ma, and radiating throughout the world during the Oligocene. This independently derived conclusion is consistent with the passerine fossil record.

Retrophylogenomics place tarsiers on the evolutionary branch of anthropoids.

One of the most disputed issues in primate evolution and thus of our own primate roots, is the phylogenetic position of the Southeast Asian tarsier. While much molecular data indicate a basal place in the primate tree shared with strepsirrhines (prosimian monophyly hypothesis), data also exist supporting either an earlier divergence in primates (tarsier-first hypothesis) or a close relationship with anthropoid primates (Haplorrhini hypothesis). The use of retroposon insertions embedded in the Tarsius genome afforded us the unique opportunity to directly test all three hypotheses via three pairwise genome alignments. From millions of retroposons, we found 104 perfect orthologous insertions in both tarsiers and anthropoids to the exclusion of strepsirrhines, providing conflict-free evidence for the Haplorrhini hypothesis, and none supporting either of the other two positions. Thus, tarsiers are clearly the sister group to anthropoids in the clade Haplorrhini.

Oligonucleotide primers for targeted amplification of single-copy nuclear genes in apocritan Hymenoptera.

BACKGROUND: Published nucleotide sequence data from the mega-diverse insect order Hymenoptera (sawflies, bees, wasps, and ants) are taxonomically scattered and still inadequate for reconstructing a well-supported phylogenetic tree for the order. The analysis of comprehensive multiple gene data sets obtained via targeted PCR could provide a cost-effective solution to this problem. However, oligonucleotide primers for PCR amplification of nuclear genes across a wide range of hymenopteran species are still scarce. FINDINGS: Here we present a suite of degenerate oligonucleotide primer pairs for PCR amplification of 154 single-copy nuclear protein-coding genes from Hymenoptera. These primers were inferred from genome sequence data from nine Hymenoptera (seven species of ants, the honeybee, and the parasitoid wasp Nasonia vitripennis). We empirically tested a randomly chosen subset of these primer pairs for amplifying target genes from six Hymenoptera, representing the families Chrysididae, Crabronidae, Gasteruptiidae, Leucospidae, Pompilidae, and Stephanidae. Based on our results, we estimate that these primers are suitable for studying a large number of nuclear genes across a wide range of apocritan Hymenoptera (i.e., all hymenopterans with a wasp-waist) and of aculeate Hymenoptera in particular (i.e., apocritan wasps with stingers). CONCLUSIONS: The amplified nucleotide sequences are (a) with high probability from single-copy genes, (b) easily generated at low financial costs, especially when compared to phylogenomic approaches, (c) easily sequenced by means of an additionally provided set of sequencing primers, and (d) suitable to address a wide range of phylogenetic questions and to aid rapid species identification via barcoding, as many amplicons contain both exonic and fast-evolving intronic nucleotides.

Genomic and morphological evidence converge to resolve the enigma of Strepsiptera.

The phylogeny of insects, one of the most spectacular radiations of life on earth, has received considerable attention. However, the evolutionary roots of one intriguing group of insects, the twisted-wing parasites (Strepsiptera), remain unclear despite centuries of study and debate. Strepsiptera exhibit exceptional larval developmental features, consistent with a predicted step from direct (hemimetabolous) larval development to complete metamorphosis that could have set the stage for the spectacular radiation of metamorphic (holometabolous) insects. Here we report the sequencing of a Strepsiptera genome and show that the analysis of sequence-based genomic data (comprising more than 18 million nucleotides from nearly 4,500 genes obtained from a total of 13 insect genomes), along with genomic metacharacters, clarifies the phylogenetic origin of Strepsiptera and sheds light on the evolution of holometabolous insect development. Our results provide overwhelming support for Strepsiptera as the closest living relatives of beetles (Coleoptera). They demonstrate that the larval developmental features of Strepsiptera, reminiscent of those of hemimetabolous insects, are the result of convergence. Our analyses solve the long-standing enigma of the evolutionary roots of Strepsiptera and reveal that the holometabolous mode of insect development is more malleable than previously thought.