Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters

Affiliation country
Publication year range
1.
Proc Natl Acad Sci U S A ; 121(21): e2313599121, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38739790

ABSTRACT

The ecoevolutionary drivers of species niche expansion or contraction are critical for biodiversity but challenging to infer. Niche expansion may be promoted by local adaptation or constrained by physiological performance trade-offs. For birds, evolutionary shifts in migratory behavior permit the broadening of the climatic niche by expansion into varied, seasonal environments. Broader niches can be short-lived if diversifying selection and geography promote speciation and niche subdivision across climatic gradients. To illuminate niche breadth dynamics, we can ask how "outlier" species defy constraints. Of the 363 hummingbird species, the giant hummingbird (Patagona gigas) has the broadest climatic niche by a large margin. To test the roles of migratory behavior, performance trade-offs, and genetic structure in maintaining its exceptional niche breadth, we studied its movements, respiratory traits, and population genomics. Satellite and light-level geolocator tracks revealed an >8,300-km loop migration over the Central Andean Plateau. This migration included a 3-wk, ~4,100-m ascent punctuated by upward bursts and pauses, resembling the acclimatization routines of human mountain climbers, and accompanied by surging blood-hemoglobin concentrations. Extreme migration was accompanied by deep genomic divergence from high-elevation resident populations, with decisive postzygotic barriers to gene flow. The two forms occur side-by-side but differ almost imperceptibly in size, plumage, and respiratory traits. The high-elevation resident taxon is the world's largest hummingbird, a previously undiscovered species that we describe and name here. The giant hummingbirds demonstrate evolutionary limits on niche breadth: when the ancestral niche expanded due to evolution (or loss) of an extreme migratory behavior, speciation followed.


Subject(s)
Animal Migration , Birds , Genetic Speciation , Animals , Animal Migration/physiology , Birds/genetics , Birds/physiology , Birds/classification , Ecosystem , Altitude , Biological Evolution
2.
Environ Res ; 249: 118229, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38325785

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) in the environment pose persistent and complex threats to human and wildlife health. Around the world, PFAS point sources such as military bases expose thousands of populations of wildlife and game species, with potentially far-reaching implications for population and ecosystem health. But few studies shed light on the extent to which PFAS permeate food webs, particularly ecologically and taxonomically diverse communities of primary and secondary consumers. Here we conducted >2000 assays to measure tissue-concentrations of 17 PFAS in 23 species of mammals and migratory birds at Holloman Air Force Base (AFB), New Mexico, USA, where wastewater catchment lakes form biodiverse oases. PFAS concentrations were among the highest reported in animal tissues, and high levels have persisted for at least three decades. Twenty of 23 species sampled at Holloman AFB were heavily contaminated, representing middle trophic levels and wetland to desert microhabitats, implicating pathways for PFAS uptake: ingestion of surface water, sediments, and soil; foraging on aquatic invertebrates and plants; and preying upon birds or mammals. The hazardous long carbon-chain form, perfluorooctanosulfonic acid (PFOS), was most abundant, with liver concentrations averaging >10,000 ng/g wet weight (ww) in birds and mammals, respectively, and reaching as high 97,000 ng/g ww in a 1994 specimen. Perfluorohexanesulfonic acid (PFHxS) averaged thousands of ng/g ww in the livers of aquatic birds and littoral-zone house mice, but one order of magnitude lower in the livers of upland desert rodent species. Piscivores and upland desert songbirds were relatively uncontaminated. At control sites, PFAS levels were strikingly lower on average and different in composition. In sum, legacy PFAS at this desert oasis have permeated local aquatic and terrestrial food webs across decades, severely contaminating populations of resident and migrant animals, and exposing people via game meat consumption and outdoor recreation.


Subject(s)
Birds , Environmental Monitoring , Fluorocarbons , Animals , New Mexico , Fluorocarbons/analysis , Humans , Birds/metabolism , Mammals , Environmental Pollutants/analysis , Food Chain , Desert Climate , Environmental Exposure
3.
PLoS One ; 19(5): e0296478, 2024.
Article in English | MEDLINE | ID: mdl-38820381

ABSTRACT

More than tools for managing physical and digital objects, museum collection management systems (CMS) serve as platforms for structuring, integrating, and making accessible the rich data embodied by natural history collections. Here we describe Arctos, a scalable community solution for managing and publishing global biological, geological, and cultural collections data for research and education. Specific goals are to: (1) Describe the core features and implementation of Arctos for a broad audience with respect to the biodiversity informatics principles that enable high quality research; (2) Highlight the unique aspects of Arctos; (3) Illustrate Arctos as a model for supporting and enhancing the Digital Extended Specimen concept; and (4) Emphasize the role of the Arctos community for improving data discovery and enabling cross-disciplinary, integrative studies within a sustainable governance model. In addition to detailing Arctos as both a community of museum professionals and a collection database platform, we discuss how Arctos achieves its richly annotated data by creating a web of knowledge with deep connections between catalog records and derived or associated data. We also highlight the value of Arctos as an educational resource. Finally, we present the financial model of fiscal sponsorship by a nonprofit organization, implemented in 2022, to ensure the long-term success and sustainability of Arctos.


Subject(s)
Museums , Humans , Biodiversity , Natural History
4.
Rev. peru. biol. (Impr.) ; 24(1)ene. 2017.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1508798

ABSTRACT

En Perú Andigena nigrirostris es considerado hipotético al no existir registros publicados. A la fecha han sido colectados diez especímenes, se han obtenido dos grabaciones de sonido y la fotografía de un individuo. Siendo este último, el único registro dentro de un área natural protegida en Perú, el Santuario Nacional Tabaconas Namballe. Los registros indican que esta especie se distribuye en los bosques montanos de la vertiente oriental, al norte de la depresión de Huancabamba, entre ~ 2200 a 2900 m de altitud.


In Peru Andigena nigrirostris is considered hypothetical due to the absence of published records. To date ten specimens have been collected and two sound records and a photograph of a free-flying individual have been obtained. The latter record was from a protected area in Peru, the Santuario Nacional Tabaconas Namballe. Records indicate that this species is distributed in the montane forests of the eastern slope, north of the Huancabamba depression, between ~ 2200 a 2900 m elevation.

SELECTION OF CITATIONS
SEARCH DETAIL