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1.
Proc Natl Acad Sci U S A ; 121(21): e2313599121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38739790

RESUMO

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.


Assuntos
Migração Animal , Aves , Especiação Genética , Animais , Migração Animal/fisiologia , Aves/genética , Aves/fisiologia , Aves/classificação , Ecossistema , Altitude , Evolução Biológica
2.
An Acad Bras Cienc ; 96(2): e20230901, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747839

RESUMO

Fishermen-hunter-gatherers of sambaquis (Brazilian shell mounds) had an intimate affinity with marine-coastal environments, where they exploited a great variety of fish and mollusks that comprise the best documented fauna from sambaquis. However, other groups of animals as mammals, birds, reptiles, and amphibians are also present in these sites, but are relatively less studied. This paper is the first one focused exclusively on the Tetrapoda biodiversity of sambaquis and aimed to identify tetrapods of ten sites from southern Brazil. We present a faunal inventory and data regarding animal capture and environmental exploitation. We identified the specimens anatomically and taxonomically, analyzed them concerning fragmentation, and quantified the data for the number of identified specimens (NISP) and minimum number of individuals (MNI). Despite the high degree of fragmentation of remains, we identified 46 taxa. As expected, most were from marine animals: cetaceans (total NISP = 2,568 and MNI = 27), otariids (total NISP = 248 and MNI = 32), and seabirds (total NISP = 65 and MNI = 23), indicating great relevance of marine tetrapod fauna as a resource for sambaqui builders (79.39% of NISP). We thus document the close bond between fishermen-hunter-gatherers of sambaquis and the marine tetrapods in southern Brazil.


Assuntos
Biodiversidade , Animais , Brasil , Aves/classificação , Répteis/classificação , Cetáceos/classificação
3.
ScientificWorldJournal ; 2024: 5592074, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38665230

RESUMO

Exploring avian species diversity and distribution patterns is vigorous for conservation efforts in biodiversity-rich countries such as Ethiopia. Compared to other species, birds are relatively well-known and easily observed, making them great markers of productivity or biodiversity. Although bird species are found all across the world, their survival and range have been negatively impacted by habitat loss, fragmentation, and destruction. Thus, the goal of this study is to provide baseline data on avifaunal diversity in the Northeast of Addis Ababa, including species richness, distribution, and relative abundance in various habitats conducted from January 2023 to September 2023 using a stratified sampling design into three habitat types: settlement, farmland, and abattoir. A fixed-width line transect sampling method was used at the farmland and settlement, and a point transect was employed at the abattoir site to collect the bird data. The data were compared using Mann-Whitney and Kruskal-Wallis statistical tests in both seasons and habitat types. A total of 42 bird species belonging to twenty-three families, and nine orders were recorded during the study period. Of these, blue-winged goose and wattled ibis are endemic to Ethiopia. Hooded vultures and White-backed vultures are critically endangered species. The mean abundance of bird species significantly varied in the three habitat types (χ2 = 13.6, df = 2, p=0.001). The abundance of bird species was nonsignificant difference between wet and dry seasons (U = -0.874, p=0.381). The highest diversity (H' = 2.74) was recorded at settlement, and the lowest diversity index (H' = 1.09) was recorded at the abattoir in the dry season. In the wet season, the highest diversity (H' = 2.66) was recorded in the farmland, and the lowest (H' = 1.08) was recorded at the abattoir. The highest evenness (J = 0.94 and J = 0.93) was recorded on the farmland in the wet and dry seasons, respectively. In the study area, urbanization is extremely impacting the environment and altering ecosystem services upon which human civilization depends. Most of the avian species observed in the study area are capable and tolerant of human-induced habitats in the city. Therefore, city planners must consider conserving urban bird species' habitats and feeding sites.


Assuntos
Biodiversidade , Aves , Etiópia , Animais , Aves/classificação , Aves/fisiologia , Ecossistema , Conservação dos Recursos Naturais , Estações do Ano
4.
Zoo Biol ; 43(3): 268-275, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482887

RESUMO

As a conservation and breeding institution for birds, Taipei Zoo plays an important role in restoring endangered species. As approximately half of all bird species are monomorphic, precisely confirming the sex of individuals is critical for the management of ex-situ conservation breeding populations, as well as for understanding the sex ratio of those in the wild. Generally, PCR is used more reliably for sex determination versus traditional methods such as plumage, behavior or hormone levels. Nevertheless, the various primer sets and annealing temperatures vary between species, and so inaccurate sexing can occasionally happen due to inadequate PCR conditions. To reduce the probability of misidentification, and to establish a PCR condition database for sex determination across the diverse range of avian taxa, we tested multiple primer sets and annealing temperatures for amplification of the bird sex-specific gene fragments (CHD1) for each captive or rescued avian species held at Taipei Zoo since 2014. A total of 162 species across 22 orders were tested using one or two primer sets. One hundred and fifty-five species were successfully sexed by the primer set 2550F/2718R and the success rate of sex typing reached over 90% of species tested in each order. Most species have suitable PCR annealing temperatures between 45°C and 55°C, and the species in the same avian taxa showed similar results in temperature. This indicates that it is possible to select the annealing temperature of other species in the same family when the species had not been tested before. We expect this study will improve the success rate of identifying sex by using applicable PCR conditions and reduce the time for searching references every time before attempts to PCR sex birds.


Assuntos
Animais de Zoológico , Aves , Análise para Determinação do Sexo , Animais , Aves/fisiologia , Aves/genética , Aves/classificação , Análise para Determinação do Sexo/métodos , Análise para Determinação do Sexo/veterinária , Taiwan , Feminino , Masculino , Reação em Cadeia da Polimerase/veterinária , Espécies em Perigo de Extinção
5.
Nature ; 622(7981): 101-106, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37758956

RESUMO

Protected areas (PAs) are the primary strategy for slowing terrestrial biodiversity loss. Although expansion of PA coverage is prioritized under the Convention on Biological Diversity, it remains unknown whether PAs mitigate declines across the tetrapod tree of life and to what extent land cover and climate change modify PA effectiveness1,2. Here we analysed rates of change in abundance of 2,239 terrestrial vertebrate populations across the globe. On average, vertebrate populations declined five times more slowly within PAs (-0.4% per year) than at similar sites lacking protection (-1.8% per year). The mitigating effects of PAs varied both within and across vertebrate classes, with amphibians and birds experiencing the greatest benefits. The benefits of PAs were lower for amphibians in areas with converted land cover and lower for reptiles in areas with rapid climate warming. By contrast, the mitigating impacts of PAs were consistently augmented by effective national governance. This study provides evidence for the effectiveness of PAs as a strategy for slowing tetrapod declines. However, optimizing the growing PA network requires targeted protection of sensitive clades and mitigation of threats beyond PA boundaries. Provided the conditions of targeted protection, adequate governance and well-managed landscapes are met, PAs can serve a critical role in safeguarding tetrapod biodiversity.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Filogenia , Vertebrados , Animais , Aves/classificação , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Vertebrados/classificação , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Anfíbios/classificação , Répteis/classificação , Aquecimento Global/estatística & dados numéricos
6.
Nature ; 621(7978): 336-343, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37674081

RESUMO

Birds are descended from non-avialan theropod dinosaurs of the Late Jurassic period, but the earliest phase of this evolutionary process remains unclear owing to the exceedingly sparse and spatio-temporally restricted fossil record1-5. Information about the early-diverging species along the avialan line is crucial to understand the evolution of the characteristic bird bauplan, and to reconcile phylogenetic controversies over the origin of birds3,4. Here we describe one of the stratigraphically youngest and geographically southernmost Jurassic avialans, Fujianvenator prodigiosus gen. et sp. nov., from the Tithonian age of China. This specimen exhibits an unusual set of morphological features that are shared with other stem avialans, troodontids and dromaeosaurids, showing the effects of evolutionary mosaicism in deep avialan phylogeny. F. prodigiosus is distinct from all other Mesozoic avialan and non-avialan theropods in having a particularly elongated hindlimb, suggestive of a terrestrial or wading lifestyle-in contrast with other early avialans, which exhibit morphological adaptations to arboreal or aerial environments. During our fieldwork in Zhenghe where F. prodigiosus was found, we discovered a diverse assemblage of vertebrates dominated by aquatic and semi-aquatic species, including teleosts, testudines and choristoderes. Using in situ radioisotopic dating and stratigraphic surveys, we were able to date the fossil-containing horizons in this locality-which we name the Zhenghe Fauna-to 148-150 million years ago. The diversity of the Zhenghe Fauna and its precise chronological framework will provide key insights into terrestrial ecosystems of the Late Jurassic.


Assuntos
Aves , Dinossauros , Fósseis , Animais , China , Dinossauros/anatomia & histologia , Dinossauros/classificação , Ecossistema , Mosaicismo , Filogenia , Aves/anatomia & histologia , Aves/classificação , História Antiga , Membro Posterior
7.
Nat Commun ; 14(1): 914, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36854679

RESUMO

The systematics of Madagascar's extinct elephant birds remains controversial due to large gaps in the fossil record and poor biomolecular preservation of skeletal specimens. Here, a molecular analysis of 1000-year-old fossil eggshells provides the first description of elephant bird phylogeography and offers insight into the ecology and evolution of these flightless giants. Mitochondrial genomes from across Madagascar reveal genetic variation that is correlated with eggshell morphology, stable isotope composition, and geographic distribution. The elephant bird crown is dated to ca. 30 Mya, when Madagascar is estimated to have become less arid as it moved northward. High levels of between-clade genetic variation support reclassifying Mullerornis into a separate family. Low levels of within-clade genetic variation suggest there were only two elephant bird genera existing in southern Madagascar during the Holocene. However, we find an eggshell collection from Madagascar's far north that represents a unique lineage of Aepyornis. Furthermore, divergence within Aepyornis coincides with the aridification of Madagascar during the early Pleistocene ca. 1.5 Ma, and is consistent with the fragmentation of populations in the highlands driving diversification and the evolution of extreme gigantism over shorts timescales. We advocate for a revision of their taxonomy that integrates palaeogenomic and palaeoecological perspectives.


Assuntos
Aves , Casca de Ovo , Fósseis , Animais , Aves/classificação , Extinção Biológica
8.
Science ; 379(6632): 527, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36758088

RESUMO

Two manifestos offer recommendations for shifting field's flawed "northern lens".


Assuntos
Aves , Viés de Publicação , Zoologia , Animais , Aves/classificação , Zoologia/normas , Zoologia/tendências , Barreiras de Comunicação
9.
Mol Ecol ; 32(11): 2898-2912, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36847070

RESUMO

Telomeres, the short DNA sequences that protect chromosome ends, are an ancient molecular structure, which is highly conserved across most eukaryotes. Species differ in their telomere lengths, but the causes of this variation are not well understood. Here, we demonstrate that mean early-life telomere length is an evolutionary labile trait across 57 bird species (representing 35 families in 12 orders) with the greatest trait diversity found among passerines. Among these species, telomeres are significantly shorter in fast-lived than in slow-lived species, suggesting that telomere length may have evolved to mediate trade-offs between physiological requirements underlying the diversity of pace-of-life strategies in birds. This association was attenuated when excluding studies that may include interstitial telomeres in the estimation of mean telomere length. Curiously, within some species, larger individual chromosome size predicts longer telomere lengths on that chromosome, leading to the hypothesis that telomere length also covaries with chromosome length across species. We show that longer mean chromosome length or genome size tends to be associated with longer mean early-life telomere length (measured across all chromosomes) within a phylogenetic framework constituting up to 31 bird species. These associations were strengthened when excluding highly influential outliers. However, sensitivity analyses suggested that they were susceptible to sample size effects and not robust to the exclusion of studies that may include interstitial telomeres. Combined, our analyses generalize patterns previously found within a few species and provide potential adaptive explanations for the 10-fold variation in telomere lengths observed among birds.


Assuntos
Aves , Estruturas Cromossômicas , Características de História de Vida , Filogenia , Homeostase do Telômero , Aves/classificação , Aves/genética , Animais , Estruturas Cromossômicas/genética , Tamanho do Genoma/genética , Análise Citogenética
10.
Braz. j. biol ; 83: 1-7, 2023. map, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468971

RESUMO

Birds are very valuable indicators of species richness and endemic patterns in a specified ecosystem, which eventually help the scientist to measure the environmental degradation. The aim of present study was to know human knowledge and attitude toward urban birds in Faisalabad city, Pakistan. The study conducted in four consecutive months: November 2019 to February 2020. Population of birds was noted from eight residential towns of Faisalabad city, data were collected through questionnaire. Faisalabad has a reasonably large population of birds and present data show that, there is a significant difference between favorite bird of residential areas and institutions. The pigeon received the most likeness in bird population among residential area residents, while the myna received the least. The most popular bird in Faisalabad institutions was the sparrow, while the least popular bird was the common myna. Bird adaptation percentage of residential areas and institutional areas of Faisalabad was the highest for parrot and sparrow respectively. People in residential areas and institutions, on the other hand, adapted least to common myna. It is concluded that people of the study area like birds and offered food and high population of birds are present in study area.


Os pássaros são indicadores muito valiosos da riqueza de espécies e padrões endêmicos em um determinado ecossistema, o que acaba ajudando o cientista a medir a degradação ambiental. O objetivo do presente estudo foi conhecer o conhecimento humano e a atitude em relação às aves urbanas na cidade de Faisalabad, Paquistão. O estudo foi conduzido em quatro meses consecutivos: novembro de 2019 a fevereiro de 2020. A população de pássaros foi observada em oito cidades residenciais da cidade de Faisalabad, os dados foram coletados por meio de questionário. Faisalabad tem uma população razoavelmente grande de pássaros, e os dados atuais mostram que há uma diferença significativa entre as aves favoritas de áreas residenciais e instituições. O pombo recebeu mais semelhanças na população de pássaros entre os residentes de áreas residenciais, enquanto o myna recebeu menos. A ave mais popular nas instituições de Faisalabad era o pardal, enquanto a ave menos popular era o myna comum. A porcentagem de adaptação de pássaros em áreas residenciais e institucionais de Faisalabad foi a mais alta para papagaios e pardais, respectivamente. As pessoas em áreas residenciais e instituições, por outro lado, se adaptaram menos ao myna comum. Conclui-se que pessoas da área de estudo como pássaros e alimentos oferecidos e alta população de pássaros estão presentes na área de estudo.


Assuntos
Animais , Aves/classificação , Ecossistema
11.
Science ; 378(6623): 939, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36454817
12.
Rev. biol. trop ; 70(1)dic. 2022.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1387703

RESUMO

Resumen Introducción: México concentra alrededor del 11 % de las especies de aves del mundo, de las cuales el 20 % son endémicas del país, concentrándose el mayor número en la región occidental. Objetivo: Analizar la composición, diversidad y distribución de la avifauna a lo largo de un gradiente altitudinal en el occidente de México. Métodos: La investigación se realizó en la Reserva de la Biosfera Sierra de Manantlán. Registramos especies de aves vistas o escuchadas en 28 puntos de conteo fijos a lo largo de un gradiente de elevación de 1 000 m. La comparación de la riqueza y la completitud del muestreo se determinaron con curvas de interpolación y extrapolación. Las franjas se compararon con un Procedimiento no Paramétrico de Permutación Multirespuesta. Se usaron correlaciones y ordenaciones indirectas para analizar cambios en la riqueza y abundancia. Resultados: Registramos 129 especies (estimado: 96 % de completitud): 19 endémicas de México, 13 en alguna categoría de riesgo y 21 consideradas indicadoras. La elevación determinó la distribución y abundancia de las especies, y las franjas altitudinales más bajas, tuvieron los valores más altos de riqueza y abundancia. Conclusión: La mayor riqueza y abundancia de especies se registró a menor altitud, con un cambio significativo en la composición y tipo de especies indicadoras por franja.


Abstract Introduction: Mexico concentrates around 11 % of the world's bird species, of which 20 % are endemic to the country, with the highest number concentrated in the Western region. Objective: To analyze composition, diversity and avifaunal distribution along an elevation gradient in Western Mexico. Methods: The research was done in the Sierra de Manantlán Biosphere Reserve. We recorded seen or heard bird species in 28 fixed count points along a 1 000 m elevation gradient. Comparative richness and sampling completeness were determined with interpolation and extrapolation curves. Belts were compared with Non-Parametric Multi-Response Permutation. Correlations and indirect ordinations were used to analyze changes in richness and abundance. Results: We recorded 129 species (estimate: 96 % completeness): 19 endemics to Mexico, 13 in some risk category, and 21 considered indicators. Elevation determined the distribution and abundance of species, and the lower elevational bands, had the highest richness and abundance values. Conclusion: The highest species richness and abundance were recorded at lower elevations, with a significant change in composition and type of indicator species by belt. The numbers of endemic and at-risk species remained constant with elevation.


Assuntos
Animais , Aves/classificação , México
13.
Nature ; 612(7938): 100-105, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36450906

RESUMO

The bony palate diagnoses the two deepest clades of extant birds: Neognathae and Palaeognathae1-5. Neognaths exhibit unfused palate bones and generally kinetic skulls, whereas palaeognaths possess comparatively rigid skulls with the pterygoid and palatine fused into a single element, a condition long considered ancestral for crown birds (Neornithes)3,5-8. However, fossil evidence of palatal remains from taxa close to the origin of Neornithes is scarce, hindering strong inferences regarding the ancestral condition of the neornithine palate. Here we report a new taxon of toothed Late Cretaceous ornithurine bearing a pterygoid that is remarkably similar to those of the extant neognath clade Galloanserae (waterfowl + landfowl). Janavis finalidens, gen. et sp. nov., is generally similar to the well-known Mesozoic ornithurine Ichthyornis in its overall morphology, although Janavis is much larger and exhibits a substantially greater degree of postcranial pneumaticity. We recovered Janavis as the first-known well-represented member of Ichthyornithes other than Ichthyornis, clearly substantiating the persistence of the clade into the latest Cretaceous9. Janavis confirms the presence of an anatomically neognathous palate in at least some Mesozoic non-crown ornithurines10-12, suggesting that pterygoids similar to those of extant Galloanserae may be plesiomorphic for crown birds. Our results, combined with recent evidence on the ichthyornithine palatine12, overturn longstanding assumptions about the ancestral crown bird palate, and should prompt reevaluation of the purported galloanseran affinities of several bizarre early Cenozoic groups such as the 'pseudotoothed birds' (Pelagornithidae)13-15.


Assuntos
Aves , Fósseis , Filogenia , Animais , Aves/anatomia & histologia , Aves/classificação , Crânio/anatomia & histologia
14.
J Environ Manage ; 324: 116414, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36352718

RESUMO

The potential link between certified organic farming and biodiversity and conservation remains unexplored in Australia, despite the country having the world's largest amount of certified organic farmland and unprecedented biodiversity loss. This study modelled the spatial effects of organic farming (intensity of local farming systems), environmental heterogeneity, and urbanisation on two widely studied environmental taxa - vascular plant and bird species richness (surrogate measures of biodiversity) - in South Australia, using a unique certified organic farming postcode level dataset from 2001 to 2016 (N = 5440). The spatial Durbin error model results confirmed the positive spatial congruence of organic farming with greater vascular plant species richness, whereas only weak to no significant evidence was found for bird species richness. Landscape features (habitat heterogeneity) and green vegetation (a proxy indicator of resource availability) - rather than organic farming - appeared to be most associated with bird species richness. Both plant and bird species richness were positively associated with habitat heterogeneity (land cover diversity and elevation range), plant productivity and proportion of conservation land and water bodies. Whereas, increased anthropogenic land use for cropping and horticultural farming, soil type diversity and proximity to the coast significantly reduced species richness of both taxa. The results suggest that a multi-scale spatially refined biodiversity conservation strategy, with spatial targeting that promotes low intensive farming systems and increases landscape heterogeneity to provide quality habitat (a whole of landscape approach by incorporating private agricultural landholders), could be beneficial for biodiversity conservation.


Assuntos
Biodiversidade , Agricultura Orgânica , Animais , Austrália , Aves/classificação , Ecossistema , Agricultura Orgânica/métodos , Austrália do Sul , Conservação dos Recursos Naturais
15.
Nature ; 611(7935): 306-311, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36289328

RESUMO

Characterizing how variation in the tempo and mode of evolution has structured the phenotypic diversity of extant species is a central goal of macroevolution1-3. However, studies are typically limited to a handful of traits4-6, providing incomplete information. We analyse morphological diversification in living birds, an ecologically diverse group7, documenting structural scales from 'pan-skeletal' proportions down to the localized three-dimensional shape changes of individual bones. We find substantial variation in evolutionary modes among avian subgroups and among skeletal parts, indicating widespread mosaicism and possible differences in the structure of the macroevolutionary landscape across Earth's main environments. Water-linked groups, especially Aequorlitornithes (waterbirds), have repeatedly explored a large portion of their total morphospace, emphasizing variation in body proportions and in the shape of bones close to the body core, which are functionally related to the mechanics of locomotion8. By contrast, landbirds (Inopinaves) evolved distinct, group-specific body forms early in the aftermath of the K-Pg and subsequently emphasized local shape variation, especially in the head and distal limb bones, which interact more directly with the environment. Passerines, which comprise more than half of all bird species, show a conservative evolutionary dynamic that resulted in low disparity across all skeletal parts. Evidence for early establishment of the morphospace of living birds is clear for some skeletal parts, including beaks and the combined skeletal morphology. However, we find little evidence for early partitioning of that morphospace, contrary to more specific predictions of 'niche-filling' models1,9. Nevertheless, early divergence among broad environmental types may have caused an early divergence of evolutionary modes, suggesting an important role for environmental divergence in structuring the radiation of crown-group birds.


Assuntos
Evolução Biológica , Aves , Meio Ambiente , Fenótipo , Esqueleto , Animais , Aves/anatomia & histologia , Aves/classificação , Extremidades/anatomia & histologia , Locomoção , Esqueleto/anatomia & histologia , Mosaicismo , Bico
16.
Nature ; 608(7922): 346-352, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35896745

RESUMO

Living birds (Aves) have bodies substantially modified from the ancestral reptilian condition. The avian pelvis in particular experienced major changes during the transition from early archosaurs to living birds1,2. This stepwise transformation is well documented by an excellent fossil record2-4; however, the ontogenetic alterations that underly it are less well understood. We used embryological imaging techniques to examine the morphogenesis of avian pelvic tissues in three dimensions, allowing direct comparison with the fossil record. Many ancestral dinosaurian features2 (for example, a forward-facing pubis, short ilium and pubic 'boot') are transiently present in the early morphogenesis of birds and arrive at their typical 'avian' form after transitioning through a prenatal developmental sequence that mirrors the phylogenetic sequence of character acquisition. We demonstrate quantitatively that avian pelvic ontogeny parallels the non-avian dinosaur-to-bird transition and provide evidence for phenotypic covariance within the pelvis that is conserved across Archosauria. The presence of ancestral states in avian embryos may stem from this conserved covariant relationship. In sum, our data provide evidence that the avian pelvis, whose early development has been little studied5-7, evolved through terminal addition-a mechanism8-10 whereby new apomorphic states are added to the end of a developmental sequence, resulting in expression8,11 of ancestral character states earlier in that sequence. The phenotypic integration we detected suggests a previously unrecognized mechanism for terminal addition and hints that retention of ancestral states in development is common during evolutionary transitions.


Assuntos
Aves , Dinossauros , Desenvolvimento Embrionário , Fósseis , Pelve , Filogenia , Animais , Aves/anatomia & histologia , Aves/classificação , Aves/embriologia , Dinossauros/anatomia & histologia , Dinossauros/embriologia , Imageamento Tridimensional , Pelve/anatomia & histologia , Pelve/embriologia
17.
J Anim Ecol ; 91(8): 1651-1665, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35668666

RESUMO

Substantial global data show that many taxa are shifting their phenologies in response to climate change. For birds, migration arrival dates in breeding regions have been shifting earlier, and there is evidence that both evolutionary adaptation and behavioural flexibility influence these shifts. As more efficient flyers may be able to demonstrate more flexibility to respond to changing conditions during migratory flight, we hypothesize that differences among passerine species in flight efficiency, as reflected by morphology, may be associated with the magnitude of shifts in arrival date in response to climate warming. We applied a logistic model to 18 years of eBird data to estimate mean arrival date for 44 common passerines migrating to northeast North America. We then used linear mixed-effects models to estimate changes in mean arrival date and compared these changes to morphological proxies for flight efficiency and migratory distance using phylogenetic generalized least squares models. On average, passerine species shifted their arrival dates 0.120 days earlier each year, with 27 of the 44 species shifting to significantly earlier arrival times, and two shifting to significantly later ones. Of the 15 species with non-significant shifts, 13 trended toward earlier arrivals. Longer migration distances and higher wing aspect ratios were associated with greater shifts toward earlier arrivals. Migration distance and aspect ratio were also significantly correlated to each other. This suggests that changes in arrival date are affected by factors pertaining to migratory flight over long distances namely, flight efficiency and migration distance. These traits may be able predict the magnitude of arrival date shift, and by extension identify species that are most at risk to climate change due to inflexible arrival timing.


Assuntos
Migração Animal , Aves/fisiologia , Mudança Climática , Voo Animal/fisiologia , Asas de Animais/anatomia & histologia , Animais , Evolução Biológica , Aves/anatomia & histologia , Aves/classificação , Filogenia , Estações do Ano , Fatores de Tempo , Asas de Animais/fisiologia
18.
PLoS One ; 17(4): e0266557, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35395028

RESUMO

Acoustic monitoring has been tested as an alternative to the traditional, human-based approach of surveying birds, however studies examining the effectiveness of different acoustic methods sometimes yield inconsistent results. In this study we examined whether bird biodiversity estimated by traditional surveys of birds differs to that obtained through soundscape surveys in meadow habitats that are of special agricultural importance, and whether acoustic monitoring can deliver reliable indicators of meadows and farmland bird biodiversity. We recorded soundscape and simultaneously surveyed birds by highly skilled human-observers within a fixed (50 m and 100 m) and unlimited radius using the point-count method twice in the breeding season at 74 recording sites located in meadows, in order to compare differences in (1) bird biodiversity estimation of meadow, farmland, songbird, and all bird species and (2) the detection rate of single bird species by these two methods. We found that recorders detected more species in comparison to the human-observers who surveyed birds within a fixed radius (50 and 100 m) and fewer when detection distance for human-observers was unlimited. We did not find significant differences in the number of meadow and farmland bird species detected by recorders and observers within a 100 m radius-the most often used fixed radius in traditional human based point-counts. We also showed how detection rate of 48 the most common bird species in our study differ between these two methods. Our study showed that an acoustic survey is equally effective as human observers surveying birds within a 100 m radius in estimation of farmland and meadow bird biodiversity. These groups of species are important for agricultural landscape and commonly used as indicators of habitat quality and its changes. Even though recorders rarely detect species that remain mostly silent during the observation periods, or species that are further distant than 100 m away, we recommend using acoustic soundscape recording methods as an equally effective and more easily standardised alternative for monitoring of farmland and meadow bird biodiversity. We propose adaptation of acoustic approach to long-term, large-scale monitoring by collecting acoustic data by non-specialists, including landowners and volunteers, and analysing them in a standardised way by units supervising monitoring of agriculture landscape.


Assuntos
Acústica , Biodiversidade , Aves/classificação , Aves/fisiologia , Pradaria , Vocalização Animal/classificação , Agricultura , Animais , Ecossistema , Humanos , Voluntários
19.
PLoS One ; 17(2): e0263504, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35196342

RESUMO

As ecosystems face disruption of community dynamics and habitat loss, the idea of determining ahead of time which species can become extinct is an important subject in conservation biology. A species' vulnerability to extinction is dependent upon both intrinsic (life-history strategies, genetics) and extrinsic factors (environment, anthropogenic threats). Studies linking intrinsic traits to extinction risk have shown variable results, and to our knowledge, there has not been a systematic analysis looking at how demographic patterns in stage-specific survival and reproductive rates correlate to extinction risk. We used matrix projection models from the COMPADRE and COMADRE matrix databases and IUCN Red List status as our proxy of extinction risk to investigate if some demographic patterns are more vulnerable to extinction than others. We obtained data on demographic rates, phylogeny, and IUCN status for 159 species of herbaceous plants, trees, mammals, and birds. We calculated 14 demographic metrics related to different aspects of life history and elasticity values and analyzed whether they differ based on IUCN categories using conditional random forest analysis and phylogenetic generalized least square regressions. We mapped all species within the database, both with IUCN assessment and without, and overlaid them with biodiversity hotspots to investigate if there is bias within the assessed species and how many of the non-assessed species could use the demographic information recorded in COMPADRE and COMADRE for future IUCN assessments. We found that herbaceous perennials are more vulnerable when they mature early and have high juvenile survival rates; birds are more vulnerable with high progressive growth and reproduction; mammals are more vulnerable when they have longer generation times. These patterns may be used to assess relative vulnerability across species when lacking abundance or trend data.


Assuntos
Aves , Espécies em Perigo de Extinção , Extinção Biológica , Características de História de Vida , Mamíferos , Árvores , Animais , Viés , Aves/classificação , Conservação dos Recursos Naturais , Bases de Dados Factuais , Mamíferos/classificação , Modelos Biológicos , Filogenia , Reprodução , Árvores/classificação
20.
Sci Rep ; 12(1): 713, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027664

RESUMO

The composition of gut bacterial communities is strongly influenced by the host diet in many animal taxa. For birds, the effect of diet on the microbiomes has been documented through diet manipulation studies. However, for wild birds, most studies have drawn on literature-based information to decipher the dietary effects, thereby, overlooking individual variation in dietary intake. Here we examine how naturally consumed diets influence the composition of the crop and cloacal microbiomes of twenty-one tropical bird species, using visual and metabarcoding-based identification of consumed diets and bacterial 16S rRNA microbiome sequencing. We show that diet intakes vary markedly between individuals of the same species and that literature-based dietary guilds grossly underestimate intraspecific diet variability. Furthermore, despite an effect of literature-based dietary guild assignment of host taxa, the composition of natural diets does not align with crop and cloacal microbiome similarity. However, host-taxon specific gut bacterial lineages are positively correlated with specific diet items, indicating that certain microbes associate with different diet components in specific avian hosts. Consequently, microbiome composition is not congruent with the overall consumed diet composition of species, but specific components of a consumed diet lead to host-specific effects on gut bacterial taxa.


Assuntos
Aves/microbiologia , Aves/fisiologia , Dieta , Ingestão de Alimentos/fisiologia , Microbioma Gastrointestinal/fisiologia , Microbiota/fisiologia , Clima Tropical , Animais , Aves/classificação
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