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1.
Rev. biol. trop ; 72(1): e52860, ene.-dic. 2024. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1559315

RESUMO

Abstract Introduction: Aquatic birds (AB) are usually associated with wetlands, which provide refuge, food, and/or nesting sites for resident and migratory species. Despite their ecological importance, there is little knowledge on AB in some tropical environments, such as those found on the Colima coast. Objective: To investigate the spatial and temporal composition of the AB community in Juluapan Lagoon, Colima, Central Mexican Pacific. Methods: Monthly counts were conducted between June 2017 and May 2018 during low-tide conditions to record habitat use by AB. Species richness and bird counts were obtained to compare sampling areas; mean richness and number of individuals were compared between seasons. Results: We detected 53 species and 5 750 individuals. The highest species richness and relative abundance values were obtained in winter at the lagoon area farthest from the connection with the marine system, where anthropogenic activity is lower. Diversity was greater in zones 2 and 3 in spring, summer, and fall. Muddy flats were the most used environment, and the most frequent activity was resting. Nesting activity was only recorded in the middle of the lagoon at the mangrove during spring. "Shorebirds" and "waders" were the most dominant groups in the bird community of the Juluapan lagoon. Conclusions: This coastal wetland is a site of great biological importance for aquatic birds; thus, conservation measures should be implemented, and there should be a continuous study of the effects of anthropogenic pressure.


Resumen Introducción: Las aves acuáticas (AA) son usualmente relacionadas a los humedales debido a que éstos funcionan como sitios de refugio, alimentación y anidación de diferentes especies residentes y migratorias. Sin embargo, el conocimiento sobre las aves acuáticas en algunos humedales es nulo. Objetivo: Investigar la composición espacio-temporal de la comunidad de AA en la laguna Juluapan, Colima, en el Pacífico Central Mexicano. Métodos: Entre junio de 2017 y mayo de 2018 se llevaron a cabo conteos mensuales en condiciones de marea baja para registrar el uso de hábitat de las AA. Se obtuvieron valores de riqueza de especies y número de individuos para realizar comparaciones entre zonas de muestreo, así como el promedio del número de especies y número de individuos para comparaciones entre temporadas. Resultados: Se registraron un total de 53 especies y 5 750 individuos. Los valores de riqueza de especies y densidad de individuos fueron más altos durante invierno, en la zona más alejada al ambiente marino, donde la actividad antropogénica es menor. La diversidad tuvo valores más altos en la zona 2 y 3, durante primavera, verano y otoño. El ambiente más explotado por las aves fueron las planicies lodosas; y el descanso fue la actividad más frecuente. Asimismo, la actividad de anidación sólo se registró en el manglar de la zona media durante primavera. Las "aves playeras" y "aves zancudas" fueron los grupos más predominantes en la comunidad de aves de la laguna Juluapan. Conclusiones: Este humedal costero es un sitio de gran importancia biológica para aves acuáticas, por lo que resulta necesario la implementación de medidas de conservación, así como el estudio de los efectos por la presión antropogénica.


Assuntos
Animais , Aves/classificação , Fauna Aquática , Estudos de Amostragem , México
2.
Rev. biol. trop ; 72(1): e49359, ene.-dic. 2024. graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1559319

RESUMO

Abstract Introduction: A recent revision of the generic classification of the Trochilidae based on DNA sequences revealed many inconsistencies with the current generic classification, largely based on plumage characters subject to homoplasy, especially in the Trochilini, the largest tribe. A thorough generic reorganization brought the classification into accord with the phylogeny, but due to lack of genetic data, two species remained unclassified. One of these was the Mangrove Hummingbird, "Amazilia" boucardi, endemic to Costa Rica and included in the IUCN red list of threatened species. Objective: To obtain molecular evidence to clarify the generic relationships of "A." boucardi. Methods: We isolated DNA from tissues of this species and amplified 4 nuclear and 4 mitochondrial fragments and compared these with homologous fragments from 56 species in the Trochilini, constructing phylogenetic trees with maximum likelihood and Bayesian methods. Results: Our phylogenetic analyses confirmed the placement of boucardi in the Trochilini and definitely excluded it from Amazilia but placed it with high confidence in the genus Chrysuronia Bonaparte, 1850, within which its closest relative is C. coeruleogularis, which also inhabits mangroves. Conclusions: Our genetic data based on nuclear and mitochondrial regions clearly indicate the relationship of A. boucardi and L. coeruleogularis. Moreover, it is also supported by their habitat distribution in the mangroves of the Pacific coast of Costa Rica and Western Panama. Therefore, we suggested to exclude A. boucardi as "incertae sedis".


Resumen Introducción: Una revisión reciente de la clasificación de la familia Trochilidae con base en secuencias de ADN demostró muchas incongruencias con la clasificación genérica previa, que había sido hecho con base en caracteres del plumaje muy sujetos a homoplasia, especialmente en la tribu más grande, Trochillini. Una reorganización de los géneros logró llevar su clasificación genérica a la concordancia con la filogenia, pero debido a la ausencia de datos genéticos, dos especies permanecieron sin clasificar. Una de estas fue el colibrí de manglar Amazilia boucardi, una especie endémica de Costa Rica, considerada como amenazada en la lista roja de la UICN. Objetivo: Obtener evidencia molecular para esclarecer las relaciones genéricas de A. boucardi. Métodos: Se aisló ADN de tejidos de esta especie y se amplificaron 4 fragmentos de ADN del núcleo y 5 de la mitocondria, y se compararon con fragmentos homólogos de 56 especies en la tribu Trochillini, generando árboles filogenéticos con métodos de máxima verosimilitud y bayesiano. Resultados: Los análisis filogénticos obtenidos confirmaron la ubicación de boucardi en Trochilini y definitivamente la excluyó del género Amazilia, pero la ubicó con un alto grado de confianza en el género Chrysuronia Bonaparte, 1850, dentro los cuales su pariente más cercano es C. coeruleogularis, que también habita manglares. Conclusiones: Nuestros datos genéticos basados en regiones nucleares y mitocondriales indican claramente la relación entre A. boucardi and L. coeruleogularis. Es más, lo anterior se sustenta por su distribución en los manglares de la costa Pacífica de Costa Rica y oeste de Panamá. Por lo tanto, sugerimos excluir a A. boucardi como "incertae sedis".


Assuntos
Animais , Aves/classificação , DNA/análise , Filogenia , Costa Rica , Genes Mitocondriais
3.
Ying Yong Sheng Tai Xue Bao ; 35(7): 1979-1987, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39233428

RESUMO

We assessed the diversity, composition, and distribution of bird species in patches of semi-humid evergreen broad-leaved forest by selecting eight natural forest communities in the central Yunnan Plateau, which is a representative distribution area of semi-humid broad-leaved evergreen forest. Field observations were conducted from April to August 2023 by the sample line and sample point method, and eight survey routes of 3-4 km in length were established. The results showed that 1) A total of 1286 birds were recorded, belonging to 102 species in 7 orders and 30 families. The three most abundant families were Muscicapidae (14 species), Leiothrichidae (9 species), and Phylloscopidae (7 species); 2) Species of Oriental origin, Palaearctic origin, and widespread species accounted for 81.4%, 4.9%, and 13.7% of observations, respectively; 3) The average number of bird species surveyed in forest patches was 32.0±3.5; the Shannon index of birds was lower in secondary, semi-humid evergreen broad-leaved forests (1.536±0.110) than in primary forest communities (2.037±0.100); 4) Species composition exhibited considerable variation between patches, with the presence of dominant and common species, and the difference in rare species; 5) Considering the ecological groups of birds based on diet, invertebrate-eating and omnivorous birds, herbivorous birds, and carnivorous birds accounted for 84.3%, 11.8%, and 3.9%, respectively. The coexistence of birds with similar diets was maintained by diluting interspecific competition, mainly through partitioning of the vertical feeding space. For the conservation of bird species diversity and rare species, all patches of native semi-humid evergreenbroad-leaved forest are of conservation value.


Assuntos
Biodiversidade , Aves , Florestas , Animais , China , Aves/classificação , Árvores/crescimento & desenvolvimento , Árvores/classificação , Conservação dos Recursos Naturais
4.
PLoS One ; 19(8): e0308066, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39116162

RESUMO

The European Roller (Coracias garrulus), a long-distance migratory bird, faced a considerable decline in breeding pairs throughout Europe at the end of the 20th century. Due to conservation efforts and the installation of nesting boxes, the population of the European Roller in Serbia has made a remarkable recovery. Here, we used the variability of nucleotide sequences of the mitochondrial DNA (mtDNA) control region and 10 microsatellite loci to assess the genetic diversity and structuring, phylogeographic patterns and demographic history of this species using 224 individuals from Serbia. Our results showed moderate level of genetic diversity (HO = 0.392) and a slightly elevated level of inbreeding and homozygosity (FIS = 0.393). Genetic structuring based on microsatellite data indicated three genetic clusters, but without a clear spatial pattern. High haplotype diversity (Hd = 0.987) of the mtDNA control region sequences was detected, and neutrality tests indicated a recent demographic expansion. The phylogeographic analysis, which also included previously published sequences of the mtDNA control region, supported the subdivision into two distinct European and Asian haplogroups (ΦST = 0.712). However, the results of our study showed that a larger number of haplotypes sampled in Serbia are clustered in the Asian haplogroup as compared to previous studies, indicating a historically continuous distribution of this species and possibly a wider distribution of the subspecies Coracias garrulus semenovwi. Our results suggest that the European Roller population in Serbia is genetically stable, with no evidence of recent bottlenecks, and emphasize the importance of artificial nest boxes for promoting and maintaining population dynamics of European Rollers.


Assuntos
DNA Mitocondrial , Variação Genética , Haplótipos , Repetições de Microssatélites , Filogeografia , Sérvia , DNA Mitocondrial/genética , Animais , Repetições de Microssatélites/genética , Aves/genética , Aves/classificação , Genética Populacional , Filogenia
5.
PLoS One ; 19(8): e0305708, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39133732

RESUMO

The classification of bird species is of significant importance in the field of ornithology, as it plays an important role in assessing and monitoring environmental dynamics, including habitat modifications, migratory behaviors, levels of pollution, and disease occurrences. Traditional methods of bird classification, such as visual identification, were time-intensive and required a high level of expertise. However, audio-based bird species classification is a promising approach that can be used to automate bird species identification. This study aims to establish an audio-based bird species classification system for 264 Eastern African bird species employing modified deep transfer learning. In particular, the pre-trained EfficientNet technique was utilized for the investigation. The study adapts the fine-tune model to learn the pertinent patterns from mel spectrogram images specific to this bird species classification task. The fine-tuned EfficientNet model combined with a type of Recurrent Neural Networks (RNNs) namely Gated Recurrent Unit (GRU) and Long short-term memory (LSTM). RNNs are employed to capture the temporal dependencies in audio signals, thereby enhancing bird species classification accuracy. The dataset utilized in this work contains nearly 17,000 bird sound recordings across a diverse range of species. The experiment was conducted with several combinations of EfficientNet and RNNs, and EfficientNet-B7 with GRU surpasses other experimental models with an accuracy of 84.03% and a macro-average precision score of 0.8342.


Assuntos
Aves , Aprendizado Profundo , Animais , Aves/fisiologia , Aves/classificação , Redes Neurais de Computação , Vocalização Animal/fisiologia , Espectrografia do Som/métodos
6.
An Acad Bras Cienc ; 96(3): e20230932, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39016353

RESUMO

The lowland Atlantic Forest, at altitudes of below 500 m, is highly fragmented, and is home to many threatened species of birds. The Brazilian state of Rio de Janeiro has a high concentration of threatened birds in the Americas and is an important residual of the dense ombrophilous formations of the Atlantic Forest, which includes the Reserva Biológica União, a high priority area for conservation of Atlantic Forest birds. This study compiled empirical and secondary records of threatened birds in this reserve and discusses potential factors determining their local occurrence. Since 2008, regular observations, including transect surveys and mist-netting, in addiction to secondary data, have provided records of 306 bird species, of which 49 appear on red lists at some level (state, national or global), including 34 listed as endangered, of which 13 are listed globally, eight of them dependent on well-conserved lowland rainforest. Future studies should include new areas of the reserve, with the aim of confirming the presence of additional threatened species. The long-term conservation of this fauna will depend not only on the adequate management of the reserve, but also the reestablishment of its connectivity with adjacent forest fragments and upland areas in the state.


Assuntos
Aves , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Florestas , Animais , Brasil , Aves/classificação , Aves/fisiologia , Densidade Demográfica , Biodiversidade
7.
PLoS One ; 19(7): e0278737, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39078833

RESUMO

Despite making up one of the most ecologically diverse groups of living birds, comprising soaring, diving and giant flightless taxa, the evolutionary relationships and ecological evolution of Anseriformes (waterfowl) remain unresolved. Although Anseriformes have a comparatively rich, global Cretaceous and Paleogene fossil record, morphological datasets for this group that include extinct taxa report conflicting relationships for all known extinct taxa. Correct placement of extinct taxa is necessary to understand whether ancestral anseriform feeding ecology was more terrestrial or one of a set of diverse aquatic ecologies and to better understand avian evolution around the K-T boundary. Here, we present a new morphological dataset for Anseriformes that includes more extant and extinct taxa than any previous anseriform-focused dataset and describe a new anseriform species from the early Eocene Green River Formation of North America. The new taxon has a mediolaterally narrow bill which is rarely found in previously described anseriform fossils. The matrix created to assess the placement of this taxon comprises 41 taxa and 719 discrete morphological characters describing skeletal morphology, musculature, syringeal morphology, ecology, and behavior. We additionally combine the morphological dataset with published sequences using Bayesian methods and perform ancestral state reconstruction for select morphological, ecological and behavioral characters. We recover the new Eocene taxon as the sister taxon to (Anseranatidae+Anatidae) across all analyses, and find that the new taxon represents a novel ecology within known Anseriformes and the Green River taxa. Results provide insight into avian evolution during and following the K-Pg mass extinction and indicate that Anseriformes were likely ancestrally aquatic herbivores with rhamphothecal lamellae..


Assuntos
Anseriformes , Evolução Biológica , Fósseis , Filogenia , Animais , Fósseis/anatomia & histologia , Anseriformes/anatomia & histologia , Anseriformes/classificação , Anseriformes/genética , Aves/anatomia & histologia , Aves/classificação
8.
Naturwissenschaften ; 111(4): 40, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017742

RESUMO

The visual field of a bird defines the amount of information that can be extracted from the environment around it, using the eyes. Previous visual field research has left large phylogenetic gaps, where tropical bird species have been comparatively understudied. Using the ophthalmoscopic technique, we measured the visual fields of seven tropical seabird species, to understand what are the primary determinants of their visual fields. The visual field topographies of the seven seabird species were relatively similar, despite the two groups of Terns (Laridae) and Shearwaters (Procellariidae) being phylogenetically distant. We propose this similarity is due to their largely similar foraging ecology. These findings support previous research that foraging ecology rather than relatedness is the key determining factor behind a bird's visual field topography. Some bird species were identified to have more limited binocular fields, such as Brown Noddies (Anous stolidus) where binocularity onsets lower down within the visual field, resulting in a larger blind area about the head.


Assuntos
Aves , Clima Tropical , Campos Visuais , Animais , Campos Visuais/fisiologia , Aves/fisiologia , Aves/classificação , Especificidade da Espécie , Filogenia
9.
Dokl Biol Sci ; 517(1): 82-87, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38861069

RESUMO

Paleolandscapes of the first half of MIS 2 or the Last Glacial Maximum (LGM) were reconstructed based on the study of the first mammoth fauna locality found in the Abakan River valley and a comparison with other localities of the South Minusinsk Basin. Sediments of the Uytag geological section under study included silt interlayers underlain and overlain by sandstone rock slack fragments and were interpreted as weakly eroded diluvium. Studies of the Uytag locality made it possible to clarify the time and range of distribution in southern Siberia for several mammals (Ovis ammon, Equus ferus, Marmota baibacina, Sicista subtilis, Lagurus lagurus, and Microtus gregalis) and the Pleistocene bird Aquila chrysaetos. The age of the locality was confirmed by radiocarbon dating. The species composition of the Uytag fauna was similar to that of other localities of the same age and region. All known localities and single finds of faunal remains indicate that open steppe landscapes were widely developed in the South Minusinsk Basin during the LGM.


Assuntos
Fósseis , Sibéria , Animais , Aves/classificação , Mamutes/genética
10.
Sensors (Basel) ; 24(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38894478

RESUMO

Identification of different species of animals has become an important issue in biology and ecology. Ornithology has made alliances with other disciplines in order to establish a set of methods that play an important role in the birds' protection and the evaluation of the environmental quality of different ecosystems. In this case, the use of machine learning and deep learning techniques has produced big progress in birdsong identification. To make an approach from AI-IoT, we have used different approaches based on image feature comparison (through CNNs trained with Imagenet weights, such as EfficientNet or MobileNet) using the feature spectrogram for the birdsong, but also the use of the deep CNN (DCNN) has shown good performance for birdsong classification for reduction of the model size. A 5G IoT-based system for raw audio gathering has been developed, and different CNNs have been tested for bird identification from audio recordings. This comparison shows that Imagenet-weighted CNN shows a relatively high performance for most species, achieving 75% accuracy. However, this network contains a large number of parameters, leading to a less energy efficient inference. We have designed two DCNNs to reduce the amount of parameters, to keep the accuracy at a certain level, and to allow their integration into a small board computer (SBC) or a microcontroller unit (MCU).


Assuntos
Aves , Redes Neurais de Computação , Vocalização Animal , Animais , Aves/fisiologia , Aves/classificação , Vocalização Animal/fisiologia , Aprendizado de Máquina , Internet das Coisas , Inteligência Artificial , Aprendizado Profundo , Algoritmos
11.
Biol Rev Camb Philos Soc ; 99(5): 1831-1847, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38705863

RESUMO

Plant-hummingbird interactions are considered a classic example of coevolution, a process in which mutually dependent species influence each other's evolution. Plants depend on hummingbirds for pollination, whereas hummingbirds rely on nectar for food. As a step towards understanding coevolution, this review focuses on the macroevolutionary consequences of plant-hummingbird interactions, a relatively underexplored area in the current literature. We synthesize prior studies, illustrating the origins and dynamics of hummingbird pollination across different angiosperm clades previously pollinated by insects (mostly bees), bats, and passerine birds. In some cases, the crown age of hummingbirds pre-dates the plants they pollinate. In other cases, plant groups transitioned to hummingbird pollination early in the establishment of this bird group in the Americas, with the build-up of both diversities coinciding temporally, and hence suggesting co-diversification. Determining what triggers shifts to and away from hummingbird pollination remains a major open challenge. The impact of hummingbirds on plant diversification is complex, with many tropical plant lineages experiencing increased diversification after acquiring flowers that attract hummingbirds, and others experiencing no change or even a decrease in diversification rates. This mixed evidence suggests that other extrinsic or intrinsic factors, such as local climate and isolation, are important covariables driving the diversification of plants adapted to hummingbird pollination. To guide future studies, we discuss the mechanisms and contexts under which hummingbirds, as a clade and as individual species (e.g. traits, foraging behaviour, degree of specialization), could influence plant evolution. We conclude by commenting on how macroevolutionary signals of the mutualism could relate to coevolution, highlighting the unbalanced focus on the plant side of the interaction, and advocating for the use of species-level interaction data in macroevolutionary studies.


Assuntos
Evolução Biológica , Aves , Polinização , Animais , Polinização/fisiologia , Aves/fisiologia , Aves/classificação , Plantas/classificação , Plantas/genética , Fenômenos Fisiológicos Vegetais
12.
Genome ; 67(9): 307-315, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38722237

RESUMO

Avian genomes are characterized as being more compact than other amniotes, with less diversity and density of transposable elements (TEs). In addition, birds usually show bimodal karyotypes, exhibiting a great variation in diploid numbers. Some species present unusually large sex chromosomes, possibly due to the accumulation of repetitive sequences. Avian retrotransposon-like element (AviRTE) is a long interspersed nuclear element (LINE) recently discovered in the genomes of birds and nematodes, and it is still poorly characterized in terms of chromosomal mapping and phylogenetic relationships. In this study, we mapped AviRTE isolated from the Trogon surrucura genome into the T. surrucura (TSU) karyotype. Furthermore, we analyzed the phylogenetic relationships of this LINE in birds and other vertebrates. Our results showed that the distribution pattern of AviRTE is not restricted to heterochromatic regions, with accumulation on the W chromosome of TSU, yet another species with an atypical sex chromosome and TE hybridization. The phylogenetic analysis of AviRTE sequences in birds agreed with the proposed phylogeny of species in most clades, and allowed the detection of this sequence in other species, expanding the distribution of the element.


Assuntos
Aves , Mapeamento Cromossômico , Cariótipo , Filogenia , Retroelementos , Cromossomos Sexuais , Animais , Aves/genética , Aves/classificação , Cromossomos Sexuais/genética , Masculino , Feminino , Elementos Nucleotídeos Longos e Dispersos
13.
An Acad Bras Cienc ; 96(1): e20220691, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808806

RESUMO

We evaluated the bird composition, forest dependence, trophic guilds and avian representativeness associated with 7, 10 and 15 years old reforestations and mature forest patches in order to verify the successional process and avian contribution to the forest restoration. Analyses revealed a segregation of bird composition with a gradual increasing in forest dependent species from 7 years to mature forest. Detrended Correspondence Analysis ranged from those birds often present in semi-open habitats to forest birds, canopy frugivorous and understory insectivorous as the successional stages progressed from the most recent reforestation to the most mature. Although 7 and 10 years of reforestation had the largest composition range, the more generalist, granivorous and forest independent birds, three years were enough to have different bird diversity between them. Avifauna of 15 years patches resembled most closely that of mature forest but still lacked 18 species. In this way, we addressed: 1) planting of herbaceous/shrub and freshy-fruited species in reforestations and; 2) establish riparian forest corridors along the Paraná river to connect these reforestation patches with mature forest. These measures will allow higher avian beta-diversity to maximize the diaspores dispersed by birds to expand and accelerate the rehabilitation of this threatened for forest.


Assuntos
Biodiversidade , Aves , Conservação dos Recursos Naturais , Florestas , Animais , Aves/fisiologia , Aves/classificação , Brasil , Fatores de Tempo , Dinâmica Populacional
14.
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
15.
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
16.
G3 (Bethesda) ; 14(7)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38626302

RESUMO

The accessibility of genomic tools in evolutionary biology has allowed for a thorough exploration of various evolutionary processes associated with adaptation and speciation. However, genomic studies in natural systems present numerous challenges, reflecting the inherent complexities of studying organisms in their native habitats. The utilization of museum specimens for genomics research has received increased attention in recent times, facilitated by advancements in ancient DNA techniques. In this study, we have utilized a museum genomics approach to analyze historic specimens of Woolly-necked storks (Ciconia spp.) and examine their genetic composition and taxonomic status and explore the evolutionary and adaptive trajectories of populations over the years. The Woolly-necked storks are distributed in Asia and Africa with a taxonomic classification that has been a matter of ambiguity. Asian and African Woollynecks were recently recognized as different species based on their morphological differences; however, their genomic validation was lacking. In this study, we have used ∼70-year-old museum samples for whole-genome population-scale sequencing. Our study has revealed that Asian and African Woollynecks are genetically distinct, consistent with the current taxonomic classification based on morphological features. However, we also found a high genetic divergence between the Asian subspecies Ciconia episcopus neglecta and Ciconia episcopus episcopus, suggesting this classification requires a detailed examination to explore processes of ongoing speciation. Because taxonomic classification directly impacts conservation efforts, and there is evidence of declining populations of Asian Woollynecks in Southeast Asia, our results highlight that population-scale studies are urgent to determine the genetic, ecological, and phylogenetic diversity of these birds.


Assuntos
Aves , Genômica , Museus , Filogenia , Animais , Genômica/métodos , Aves/genética , Aves/classificação , Evolução Biológica , Genoma , Evolução Molecular , Variação Genética
17.
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
18.
Nature ; 629(8013): 851-860, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38560995

RESUMO

Despite tremendous efforts in the past decades, relationships among main avian lineages remain heavily debated without a clear resolution. Discrepancies have been attributed to diversity of species sampled, phylogenetic method and the choice of genomic regions1-3. Here we address these issues by analysing the genomes of 363 bird species4 (218 taxonomic families, 92% of total). Using intergenic regions and coalescent methods, we present a well-supported tree but also a marked degree of discordance. The tree confirms that Neoaves experienced rapid radiation at or near the Cretaceous-Palaeogene boundary. Sufficient loci rather than extensive taxon sampling were more effective in resolving difficult nodes. Remaining recalcitrant nodes involve species that are a challenge to model due to either extreme DNA composition, variable substitution rates, incomplete lineage sorting or complex evolutionary events such as ancient hybridization. Assessment of the effects of different genomic partitions showed high heterogeneity across the genome. We discovered sharp increases in effective population size, substitution rates and relative brain size following the Cretaceous-Palaeogene extinction event, supporting the hypothesis that emerging ecological opportunities catalysed the diversification of modern birds. The resulting phylogenetic estimate offers fresh insights into the rapid radiation of modern birds and provides a taxon-rich backbone tree for future comparative studies.


Assuntos
Aves , Evolução Molecular , Genoma , Filogenia , Animais , Aves/genética , Aves/classificação , Aves/anatomia & histologia , Encéfalo/anatomia & histologia , Extinção Biológica , Genoma/genética , Genômica , Densidade Demográfica , Masculino , Feminino
19.
Mol Ecol ; 33(11): e17353, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38613250

RESUMO

Effective population size (Ne) is a particularly useful metric for conservation as it affects genetic drift, inbreeding and adaptive potential within populations. Current guidelines recommend a minimum Ne of 50 and 500 to avoid short-term inbreeding and to preserve long-term adaptive potential respectively. However, the extent to which wild populations reach these thresholds globally has not been investigated, nor has the relationship between Ne and human activities. Through a quantitative review, we generated a dataset with 4610 georeferenced Ne estimates from 3829 populations, extracted from 723 articles. These data show that certain taxonomic groups are less likely to meet 50/500 thresholds and are disproportionately impacted by human activities; plant, mammal and amphibian populations had a <54% probability of reaching N ̂ e = 50 and a <9% probability of reaching N ̂ e = 500. Populations listed as being of conservation concern according to the IUCN Red List had a smaller median N ̂ e than unlisted populations, and this was consistent across all taxonomic groups. N ̂ e was reduced in areas with a greater Global Human Footprint, especially for amphibians, birds and mammals, however relationships varied between taxa. We also highlight several considerations for future works, including the role that gene flow and subpopulation structure plays in the estimation of N ̂ e in wild populations, and the need for finer-scale taxonomic analyses. Our findings provide guidance for more specific thresholds based on Ne and help prioritise assessment of populations from taxa most at risk of failing to meet conservation thresholds.


Assuntos
Anfíbios , Conservação dos Recursos Naturais , Genética Populacional , Mamíferos , Densidade Demográfica , Animais , Anfíbios/genética , Anfíbios/classificação , Mamíferos/genética , Mamíferos/classificação , Fluxo Gênico , Aves/genética , Aves/classificação , Humanos , Endogamia , Deriva Genética , Plantas/genética , Plantas/classificação , Atividades Humanas
20.
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
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