Myo-inositol is a key regulator of avian metabolism: From mechanisms to seasonal behavior.

Being naturally hyperglycemic and insulin insensitive, birds maintain plasma glucose levels twice as high as mammals of similar size. Recent evidence suggests that perturbation of myo-inositol (MI) plays a role in mammalian hyperglycemic regulation. Using an integrative approach, we identify a fundamental role of MI in avian metabolism.

A Highly Contiguous Genome Assembly for the Wrentit (Chamaea Fasciata), the Sole Representative of the Babbler Radiation in the Americas.

The wrentit (Chamaea fasciata) is a chaparral and scrub specialist bird found from coastal Oregon to northern Baja California. We generated a draft reference assembly for the species using PacBio HiFi long read and Omni-C chromatin-proximity sequencing data as part of the California Conservation Genomics Project (CCGP). Sequenced reads were assembled into 1342 scaffolds totaling 1.

Unusual Sperm Morphology in Two Sedentary Songbird Species.

Sperm morphology can differ dramatically among closely related species. Within songbirds, the typical filiform sperm has a slender, corkscrew-shaped head and an elongated midpiece coiled around the flagellum. However, three songbird species are known to have an unusual tadpole-like sperm morphology with a round or ellipsoid head and short, uncoiled midpiece, which may arise developmentally via neoteny.

The Proof Is in the Plumage: A Method for Detecting Dietary Ethanol Exposure in Birds by Testing for Ethyl Glucuronide in Feathers.

AbstractEthanol is a naturally occurring molecule produced via fermentation of sugar-rich foods by yeast. Ethanol catabolism is followed by production of secondary metabolites such as ethyl glucuronide (EtG), which can be measured to provide a retrospective view of dietary exposure. To date, occurrence of this molecule has not been studied in vertebrates other than humans and several other mammalian taxa.

Using wild-animal tracking for detecting and managing disease outbreaks.

Zoonotic diseases increasingly threaten human and wildlife populations, driving a global rise in mass-mortality outbreaks, including the ongoing avian influenza panzootic in wildlife and zoonotic spillovers such as the COVID-19 (SARS-CoV-2) pandemic in humans. We introduce a new general framework for detecting and managing pathogen outbreaks using animal movement and sensory biologging data to enhance early outbreak detection, provide near-real-time updates on sentinel host health and mortality, and reveal infection-induced behavioral changes. Integrating past and near-real-time biologging with disease surveillance data also enables prospective assessments of spatiotemporal outbreak dynamics, informs management decisions, helps to mitigate spillover risks, and supports both disease control and wildlife conservation.

A high-quality genome assembly for a desert-adapted rodent, Merriam's kangaroo rat (Dipodomys merriami).

Merriam's kangaroo rat (Dipodomys merriami) is a member of a unique family of primarily desert-adapted North American rodents (Heteromyidae). Of the 20 species in the genus, D. merriami is one of the most wide-ranging and ecologically flexible, inhabiting desert scrub, grassland, sagebrush steppe, and juniper-piñon woodland in the southwestern deserts of the United States and Mexico.

Genomic Introgression and Adaptation of Southern Seabird Species Facilitate Recent Polar Colonization.

Genomic adaptation and introgression can occur during the speciation process, enabling species to diverge in their frequencies of adaptive alleles or acquire new alleles that may promote adaptation to environmental changes. There is limited information on introgression in organisms from extreme environments and their responses to climate change. To address these questions, we focused on the 3 southern skua species, selected for their widespread distribution across the Southern Hemisphere and their complex history of speciation and introgression events.

Social, environmental, and developmental factors affect the microbiota of barn owls (Tyto alba) in a cross-fostering experiment.

Background: Species host diverse microbial communities that can impact their digestion and health, which has led to much interest in understanding the factors that influence their microbiota. We studied the developmental, environmental, and social factors that influence the microbiota of nestling barn owls (Tyto alba) through a partial cross-fostering experiment that manipulated the social and nest environment of the nestlings. We then examined the nestling microbiota before and three weeks after the exchange of nestlings between nests, along with the microbiota of the adults at the nest and nestlings in unmanipulated nests.

Comparative Genomics Supports Ecologically Induced Selection as a Putative Driver of Banded Penguin Diversification.

The relative importance of genetic drift and local adaptation in facilitating speciation remains unclear. This is particularly true for seabirds, which can disperse over large geographic distances, providing opportunities for intermittent gene flow among distant colonies that span the temperature and salinity gradients of the oceans. Here, we delve into the genomic basis of adaptation and speciation of banded penguins, Galápagos (Spheniscus mendiculus), Humboldt (Spheniscus humboldti), Magellanic (Spheniscus magellanicus), and African penguins (Spheniscus demersus), by analyzing 114 genomes from the main 16 breeding colonies.

Climate cycling did not affect haplotype distribution in an abundant Southern African avian habitat generalist species, the familiar chat (Oenanthe familiaris).

Avian species diversity in Southern Africa is remarkably high, yet the mechanisms responsible for that diversity are poorly understood. While this is particularly true with respect to species endemic to the subregion, it is unclear as to how more broadly distributed African species may have colonized southern Africa. One process that may in part account for the high bird species diversity in southern Africa is a "species pump" model, wherein the region was repeatedly colonized by lineages from areas further north: a pattern related to climate cycling and the eastern African arid corridor.

Remarkably High Repeat Content in the Genomes of Sparrows: The Importance of Genome Assembly Completeness for Transposable Element Discovery.

Transposable elements (TE) play critical roles in shaping genome evolution. Highly repetitive TE sequences are also a major source of assembly gaps making it difficult to fully understand the impact of these elements on host genomes. The increased capacity of long-read sequencing technologies to span highly repetitive regions promises to provide new insights into patterns of TE activity across diverse taxa.

A late burst of colour evolution in a radiation of songbirds (Passeriformes: Parulidae) suggests secondary contact drives signal divergence.

Evolutionary radiations provide important insights into species diversification, which is especially true of adaptive radiations. New World wood warblers (Parulidae) are a family of small, insectivorous, forest-dwelling passerine birds, often considered an exemplar of adaptive radiation due to their rapid diversification followed by a slowdown. However, they deviate from the expectations of an adaptive radiation scenario due to the lack of conspicuous morphological and ecological differentiation.

The Evolution of Multiple Color Mechanisms Is Correlated with Diversification in Sunbirds (Nectariniidae).

How and why certain groups become speciose is a key question in evolutionary biology. Novel traits that enable diversification by opening new ecological niches are likely important mechanisms. However, ornamental traits can also promote diversification by opening up novel sensory niches and thereby creating novel inter-specific interactions.

Spatial variation in population genomic responses to over a century of anthropogenic change within a tidal marsh songbird.

Combating the current biodiversity crisis requires the accurate documentation of population responses to human-induced ecological change. However, our ability to pinpoint population responses to human activities is often limited to the analysis of populations studied well after the fact. Museum collections preserve a record of population responses to anthropogenic change that can provide critical baseline data on patterns of genetic diversity, connectivity, and population structure prior to the onset of human perturbation.

Cranes soar on thermal updrafts behind cold fronts as they migrate across the sea.

Thermal soaring conditions above the sea have long been assumed absent or too weak for terrestrial migrating birds, forcing obligate soarers to take long detours and avoid sea-crossing, and facultative soarers to cross exclusively by costly flapping flight. Thus, while atmospheric convection does develop at sea and is used by some seabirds, it has been largely ignored in avian migration research. Here, we provide direct evidence for routine thermal soaring over open sea in the common crane, the heaviest facultative soarer known among terrestrial migrating birds.

Adaptive and non-adaptive convergent evolution in feather reflectance of California Channel Islands songbirds.

Convergent evolution is widely regarded as a signature of adaptation. However, testing the adaptive consequences of convergent phenotypes is challenging, making it difficult to exclude non-adaptive explanations for convergence. Here, we combined feather reflectance spectra and phenotypic trajectory analyses with visual and thermoregulatory modelling to test the adaptive significance of dark plumage in songbirds of the California Channel Islands.

A highly contiguous genome assembly for the pocket mouse Perognathus longimembris longimembris.

The little pocket mouse, Perognathus longimembris, and its nine congeners are small heteromyid rodents found in arid and seasonally arid regions of Western North America. The genus is characterized by behavioral and physiological adaptations to dry and often harsh environments, including nocturnality, seasonal torpor, food caching, enhanced osmoregulation, and a well-developed sense of hearing. Here we present a genome assembly of Perognathus longimembris longimembris generated from PacBio HiFi long read and Omni-C chromatin-proximity sequencing as part of the California Conservation Genomics Project.

De novo assembly of a chromosome-level reference genome for the California Scrub-Jay, Aphelocoma californica.

We announce the assembly of the first de novo reference genome for the California Scrub-Jay (Aphelocoma californica). The genus Aphelocoma comprises four currently recognized species including many locally adapted populations across Mesoamerica and North America. Intensive study of Aphelocoma has revealed novel insights into the evolutionary mechanisms driving diversification in natural systems.

A highly contiguous reference genome for the Steller's jay (Cyanocitta stelleri).

The Steller's jay is a familiar bird of western forests from Alaska south to Nicaragua. Here, we report a draft reference assembly for the species generated from PacBio HiFi long-read and Omni-C chromatin-proximity sequencing data as part of the California Conservation Genomics Project (CCGP). Sequenced reads were assembled into 352 scaffolds totaling 1.

Hummingbird ingestion of low-concentration ethanol within artificial nectar.

Both frugivores and nectarivores are potentially exposed to dietary ethanol produced by fermentative yeasts which metabolize sugars. Some nectarivorous mammals exhibit a preference for low-concentration ethanol solutions compared to controls of comparable caloric content, but behavioural responses to ethanol by nectar-feeding birds are unknown. We investigated dietary preference by Anna's Hummingbirds () for ethanol-enhanced sucrose solutions.

Comparative genomics of two Empidonax flycatchers reveal candidate genes for bird song production.

Whole-genome-level comparisons of sister taxa that vary in phenotype against a background of high genomic similarity can be used to identify the genomic regions that might underlie their phenotypic differences. In wild birds, this exploratory approach has detected markers associated with plumage coloration, beak and wing morphology, and complex behavioral traits like migration. Here, we use genomic comparisons of two closely related suboscine flycatchers (Empidonax difficilis and E.

A highly contiguous genome assembly for the California quail (Callipepla californica).

The California quail (Callipepla californica) is an iconic native bird of scrub and oak woodlands in California and the Baja Peninsula of Mexico. Here, we report a draft reference assembly for the species generated from PacBio HiFi long read and Omni-C chromatin-proximity sequencing data as part of the California Conservation Genomics Project (CCGP). Sequenced reads were assembled into 321 scaffolds totaling 1.

Plumage Balances Camouflage and Thermoregulation in Horned Larks ().

AbstractAnimal coloration serves many biological functions and must therefore balance potentially competing selective pressures. For example, many animals have camouflage in which coloration matches the visual background that predators scan for prey. However, different colors reflect different amounts of solar radiation and may therefore have thermoregulatory implications as well.