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Inland vagrancy and overland dispersal by seabirds arc rare phenomena for which the causes and consequences are poorly understood. Studying inland occurrences of seabirds is important because continental land masses form barriers to dispersal of genes and parasites; thus, the permeability of land barriers influences the extent to which seabird populations evolve on separate trajectories and co-evolve with distinct parasite faunas. The boobies (Sulci spp.) arc a clade of saltwater-obligate species occurring in tropical and subtropical oceans. Booby species tend to exhibit population generic structure among oceanic regions. Although they rarely wander inland, the Brown Booby (Sula leucogaster) has occurred numerous times as a vagrant in interior North America. Previous inland records from far western North America originated from Pacific populations (subspecies brewsteri), whereas those from eastern and midwestern North America originated from Caribbean populations (subspecies leucogaster). In this paper, we describe 2 new specimens of 5. leucogaster, first state records for New Mexico and Colorado, salvaged from localities nearly equidistant from Pacific and Caribbean source populations. We used mitochondrial DNA sequences to conclusively demonstrate that both specimens originated in the Caribbean. We next examined the helminth parasite fauna of the 2 S. leucogaster specimens and an inland-vagrant Blue-footed Booby (S. nebouxii) from New Mexico. The guts of these boobies contained a suite of helminths, including multiple freshwater-obligatc taxa. Based on our findings, wc suggest that susceptibility to freshwater parasites may cause overland dispersal to fail for boobies, or other seabirds. Thus, freshwater parasites may contribute to explaining the relative rarity of transcontinental dispersal, maintenance of strong inter-ocean population genetic structure, phylogenetic conservatism of specialization on salt-water habitats, and the strictly pelagic distributions of ocean-dwelling species from several avian families. Received 16 September 2022. Accepted 11 August 2023. Key words: freshwater, helminth, parasite, specimen, Sula, vagrancy. La errancia y dispersion en tierra adentro de las aves marinas son fenomenos raros cuyas causas y consecuencias se entienden poco. Estudiar registros en tierra adentro de aves marinas es importante ya que las masas continentales forman barreras a la dispersion de genes y parasitos; por lo tanto, la permeabilidad de las barreras terrestres influye en que tanto las poblaciones de aves evolucionan en trayectorias distintas y co-evolucionan con faunas parasitas distintas. Los alcatraces (Sula spp.) constituyen un ciado de especies obligadas de agua salada que se encuentran en oceanos tropicales y subtropicales. Las especies de alcatraces tienden a exhibir estructura genetica poblacional entre regiones oceanicas. Aunque raramente deambula en tierra firme, el alcatraz pardo (Sula leucogaster) se ha reportado muchas veces como errante en tierra adentro de Noneamerica. Previos reportes de tierra adentro en el lejano oeste Norteamericano se originaron de poblaciones del Pacifico (subespecies brewsteri), mientras que los del este y el medioeste de Norteamerica se originan de poblaciones del Caribe (subespecie leucogaster). En este articulo, describimos 2 especimenes nuevos de S. leucogaster, primeros registros estatales para Nuevo Mexico y Colorado, procedentes de localidades casi equidistantes de poblaciones fuente de Pacifico y el Caribe. Utilizamos secuencias de ADN mitocondrial para mostrar conclusivamente que ambos especimenes se originaron en el Caribe. Luego, examinamos ia fauna de helmintos parasitos de ambos especimenes de S. leucogaster y de un alcatraz de patas azules (S. nebouxii) que vagaba tierra adentro en Nuevo Mexico. Los intestinos de estos alcatraces contenian una serie de helmintos, incluyendo varios taxa obligadas de agua dulce. Con base en nuestros hallazgos, sugerimos que la susceptibilidad a los parasitos de agua dulce puede ocasionar que la dispersion en tierra adentro no sea exitosa para los alcatraces u otras aves marinas. Por lo tanto, los parasitos de agua dulce pueden contribuir a explicar la relativa rareza de la dispersion transcontinental, el mantenimiento de la fuerte estructura genetica inter-oceanica, la conservacion filogenetica de la especializacion en habitats de agua salada y la distribucion estrictamente pelagica de especies oceanicas pertenecientes a varias familias de aves. Palabras clave: agua dulce, errancia, especimen, helmintos, parasito, Sula., At least 254 bird species from 11 families are restricted to saltwater habitats (Howell and Zufelt 2019). The volant seabird species are strong fliers, characterized by high aspect-ratio wings. It [...]

We sequenced the mitochondrial ND2 gene for 290 Bushtits (Psaltriparus minimus) sampled from northern Washington to Guatemala. Phylogenetic analysis sorted specimens into 2 main lineages residing either west (coastal) or east (inland) of the Sierra Nevada and Cascades. These lineages are separated by 3.5% sequence divergence and correspond with the distributions of 2 long-recognized phenotype groupings (brown-capped and plumbeous, respectively). Three additional monophylctic geographically structured lineages were identified. Birds from southmost Baja California (Sierra de la Laguna) segregate from other coastal samples whereas the inland lineage includes additional lineages occurring in southeastern Mexico (Morelos, Puebla, Guerrero, and Oaxaca) plus Guatemala, and southwestern Mexico (Michoacan). Examination of museum specimens revealed that a black-eared phenotype occurs sporadically in the interior lineage in southern U.S. and northern Mexico, increasing in frequency to the south, corresponding roughly with these southern Mexican mtDNA lineages. Degree of sequence divergence between the 2 main lineages suggests a relatively early divergence, and ample time for 2-way introgression to occur. However, only 1 of our sampling localities (Lake Co., Oregon: n = 4) was mixed for coastal (n = 1) and interior (n =3) lineages suggesting the possibility of reproductive isolation between the 2 main lineages. Received 31 January 2022. Accepted 8 December 2022. Key words: gene tree, lineage divergence, mitochondrial DNA, niche models, phylogeography. Secuenciamos el gen mitocondrial ND2 de 290 mitos colectados desde el norte de Washington hasta Guatemala. Los analisis filogeneticos clasificaron a los especimenes en 2 linajes principalcs que residian ya sea en al ocste (costero) o al este (interior) de la Sierra Nevada y Cascades. Estos linajes se separan por una divergencia de secuencias de 3.5% y corresponden a distribuciones de 2 agrupamientos fenotipicos reconocidos desde hace mucho tiempo (respectivamente capucha marron y plomizo). Se reconocieron tres linajes adieionales monofilcticos cstructurados gcograficamcnte. Aves de la pane mas surena de Baja California (Sierra de la Laguna) se segregan de otras muestras costeras mientras que linajes del interior incluyen otros linajes que se encuentran en el sudeste mexicano (Morelos, Puebla, Guerrero y Oaxaca), sumado a Guatemala y al sudoeste mexicano (Michoacan). La examinaeion de especimenes de musco rcvclo que un fenotipo de oreja negra se eneuentra esporadicamente en el linaje interior en el sudeste de Estados Unidos y norte de Mexico, que aumenta su frecuencia haeia el sur y corresponde en general con linajes mtADN del sudeste mexicano. El grado de divergencia de secuencias entrc los 2 linajes principalcs sugiere una divergencia relativamente temprana y un tiempo grande para que ocurriera una introgrcsion de 2 vias. Sin embargo, solo una de las localidades de muestrco (Lake Co., Oregon, n =4) presentaba una mezela de linajes costero (n = 1) e interior (n = 3). sugiriendo la posibilidad de aislamiento reproductive) entre los 2 linajes principalcs. Palabras clave: ADN mitocondrial, arbol genctico, divergencia de linaje, filogeografia, modelos de nicho., The field of phylogeography began with the realization that mitochondrial DNA (mtDNA) could be rapidly and easily sequenced, and that the sequences could be analyzed phylogenetically in a geographic context, [...]

The Duke University Herbarium, the largest herbarium in the southeastern United States, is facing dissolution as the university no longer considers it a priority. This decision has caused concern among natural science leaders and the Duke community, as herbaria play a crucial role in research and education on biodiversity. The closure of the herbarium would have negative impacts on other US biological collections and research communities, as well as hinder the educational capacity of the university. The authors urge Duke to reconsider its plans and convene a group of experts to discuss the future of the collections. [Extracted from the article]

Trait genetic architecture plays an important role in the probability that variation in that trait leads to divergence and speciation. In some cases, speciation may be driven by the generation of novel phenotypes through the recombination of genes associated with traits that are important for local adaptation or sexual selection. Here, we investigate the genetic basis of three plumage color traits, and one ecological trait, breeding elevation, in a recent avian radiation, the North American rosy-finches (Leucosticte spp.). We identify unique genomic regions associated with each trait and highlight 11 candidate genes. Among these are well-characterized melanogenesis genes, including Mitf and Tyrp1, and previously reported hypoxia-related genes including Egln1. Additionally, we use mitochondrial data to date the divergence of rosy-finch clades which appear to have diverged within the past 250 ky. Given the low levels of genome-wide differentiation among rosy-finch taxa, and evidence for extensive introgression in North America, plumage coloration and adaptation to high elevations have likely played large roles in generating the observed patterns of lineage divergence. The relative independence of these candidate regions across the genome suggests that recombination might have led to multiple phenotypes, and subsequent rosy-finch speciation, over short periods of time. [ABSTRACT FROM AUTHOR]

Understanding how gene flow affects population divergence and speciation remains challenging. Differentiating one evolutionary process from another can be difficult because multiple processes can produce similar patterns, and more than one process can occur simultaneously. Although simple population models produce predictable results, how these processes balance in taxa with patchy distributions and complicated natural histories is less certain. These types of populations might be highly connected through migration (gene flow), but can experience stronger effects of genetic drift and inbreeding, or localized selection. Although different signals can be difficult to separate, the application of high-throughput sequence data can provide the resolution necessary to distinguish many of these processes. We present whole-genome sequence data for an avian species group with an alpine and arctic tundra distribution to examine the role that different population genetic processes have played in their evolutionary history. Rosy-finches inhabit high elevation mountaintop sky islands and high-latitude island and continental tundra. They exhibit extensive plumage variation coupled with low levels of genetic variation. Additionally, the number of species within the complex is debated, making them excellent for studying the forces involved in the process of diversification, as well as an important species group in which to investigate species boundaries. Total genomic variation suggests a broadly continuous pattern of allele frequency changes across the mainland taxa of this group in North America. However, phylogenomic analyses recover multiple distinct, well supported, groups that coincide with previously described morphological variation and current species-level taxonomy. Tests of introgression using D-statistics and approximate Bayesian computation reveal significant levels of introgression between multiple North American taxa. These results provide insight into the balance between divergent and homogenizing population genetic processes and highlight remaining challenges in interpreting conflict between different types of analytical approaches with whole-genome sequence data. [ABBA-BABA; approximate Bayesian computation; gene flow; phylogenomics; speciation; whole-genome sequencing.] [ABSTRACT FROM AUTHOR]