The Complete Genome Sequences of 37 Bird Species from the Ecuadorian Andes.

We present the complete genome sequences of 37 Ecuadorian bird species widespread throughout the tropical Andes.

Elevation and landscape change drive the distribution of a montane, endemic grassland bird.

CONTEXT: Tropical montane habitats support high biodiversity and are hotspots of endemism, with grasslands being integral components of many such landscapes. The montane grasslands of the Western Ghats have seen extensive land-use change over anthropogenic timescales. The factors influencing the ability of grassland-dependent species to persist in habitats experiencing loss and fragmentation, particularly in montane grasslands, are poorly known. OBJECTIVES: We studied the relationship between the Nilgiri pipit Anthus nilghiriensis, a threatened endemic bird that typifies these montane grasslands, and its habitat, across most of its global distribution. We examined what habitat features make remnant grasslands viable, which is necessary for their effective management. METHODS: We conducted 663 surveys in 170 sites and used both single-season occupancy modeling and N-mixture modeling to account for processes influencing detection, presence, and abundance. RESULTS: Elevation had a positive influence on species presence, patch size had a moderate positive influence, and patch isolation had a moderate negative influence. Species abundance was positively influenced by elevation and characteristics related to habitat structure, and negatively influenced by the presence of invasive woody vegetation. CONCLUSIONS: The strong effect of elevation on the highly range-restricted Nilgiri pipit is likely to make it vulnerable to climate change. This highly range-restricted species is locally extinct at several locations, and persists at low densities in remnants of its habitat left by recent fragmentation. Our findings indicate a need to control and reverse the spread of exotic woody invasives to preserve the grasslands themselves and the specialist species dependent upon them.

Digest: A single genetic origin and a role for bone development pathways in repeated losses of flight in steamer ducks.

Is there evidence for convergence in the molecular mechanisms underlying the loss of flight in the avian evolutionary tree? Campagna et al. used genomic data to investigate the genetic basis of flightlessness in steamer ducks, a recently diverged clade that is polymorphic with respect to flight. They found an association between morphological changes related to flightlessness and several genes, one of which is involved in growth and bone development, providing evidence for a single genetic origin for flightlessness.

Sequencing and analysis of the mitochondrial genome of Pituophis catenifer sayi (Squamata: Colubridae).

The complete DNA sequence of the mitochondrial genome of the bullsnake (Pituophis catenifer sayi) is presented and analyzed in this study. The genome is 17,193 bp in length, and contains 22 transfer RNA genes, 2 ribosomal RNA genes, 13 protein-coding genes and 2 control regions. The overall base composition of the H-strand is A (34.5%), T (26.2%), C (25.8%) and G (12.7%). The gene order and orientation of the mitogenome is consistent with other sequenced genomes from colubrid snakes. Phylogenetic analyses using the ML, NJ and MP methods for a set of colubrids, including every sequenced genus within the sub-family Colubrinae, produced identical trees. We show that Pituophis is most closely related to the American ratsnake genus Pantherophis.