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1.
Ecology ; 103(2): e03595, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34807455

RESUMO

Flowering plant species and their nectar-feeding vertebrates exemplify some of the most remarkable biotic interactions in the Neotropics. In the Brazilian Atlantic Forest, several species of birds (especially hummingbirds), bats, and non-flying mammals, as well as one lizard feed on nectar, often act as pollinators and contribute to seed output of flowering plants. We present a dataset containing information on flowering plants visited by nectar-feeding vertebrates and sampled at 166 localities in the Brazilian Atlantic Forest. This dataset provides information on 1902 unique interactions among 515 species of flowering plants and 129 species of potential vertebrate pollinators and the patterns of species diversity across latitudes. All plant-vertebrate interactions compiled were recorded through direct observations of visits, and no inferences of pollinators based on floral syndromes were included. We also provide information on the most common plant traits used to understand the interactions between flowers and nectar-feeding vertebrates: plant growth form, corolla length, rate of nectar production per hour in bagged flowers, nectar concentration, flower color and shape, time of anthesis, presence or absence of perceptible fragrance by human, and flowering phenology as well as the plant's threat status by International Union for Conservation of Nature (IUCN) classification. For the vertebrates, status of threat by IUCN classification, body mass, bill or rostrum size are provided. Information on the frequency of visits and pollen deposition on the vertebrate's body is provided from the original source when available. The highest number of unique interactions is recorded for birds (1771) followed by bats (110). For plants, Bromeliaceae contains the highest number of unique interactions (606), followed by Fabaceae (242) and Gesneriaceae (104). It is evident that there was geographical bias of the studies throughout the southeast of the Brazilian Atlantic Forest and that most effort was directed to flower-hummingbird interactions. However, it reflects a worldwide tendency of more plants interacting with birds compared with other vertebrate species. The lack of similar protocols among studies to collect basic data limits the comparisons among areas and generalizations. Nevertheless, this dataset represents a notable effort to organize and highlight the importance of vertebrate pollinators in this hotspot of biodiversity on Earth and represents the data currently available. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or scientific events.


Assuntos
Néctar de Plantas , Polinização , Animais , Aves , Flores , Florestas , Humanos , Mamíferos
2.
Ecol Evol ; 9(14): 7903-7913, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31380059

RESUMO

Cacao agroforestry have been considered as biodiversity-friendly farming practices by maintaining habitats for a high diversity of species in tropical landscapes. However, little information is available to evaluate whether this agrosystem can maintain functional diversity, given that agricultural changes can affect the functional components, but not the taxonomic one (e.g., species richness). Thus, considering functional traits improve the understanding of the agricultural impacts on biodiversity. Here, we measured functional diversity (functional richness-FD, functional evenness-FEve, and functional divergence-Rao) and taxonomic diversity (species richness and Simpson index) to evaluate changes of bird diversity in cacao agroforestry in comparison with nearby mature forests (old-growth forests) in the Brazilian Atlantic Forest. We used data from two landscapes with constraining areas of mature forest (49% Una and 4.8% Ilhéus) and cacao agroforestry cover (6% and 82%, respectively). To remove any bias of species richness and to evaluate assembly processes (functional overdispersion or clustering), all functional indices were adjusted using null models. Our analyses considered the entire community, as well as separately for forest specialists, habitat generalists, and birds that contribute to seed dispersal (frugivores/granivores) or invertebrate removal (insectivores). Our findings showed that small cacao agroforestry in the forested landscape sustains functional diversity (FD and FEve) as diverse as nearby forests when considering the entire community, forest specialist, and habitat generalists. However, we observed declines for frugivores/granivores and insectivores (FD and Rao). These responses of bird communities differed from those observed by taxonomic diversity, suggesting that even species-rich communities in agroforestry may capture lower functional diversity. Furthermore, communities in both landscapes showed either functional clustering or neutral processes as the main driver of functional assembly. Functional clustering may indicate that local conditions and resources were changed or lost, while neutral assemblies may reveal high functional redundancy at the landscape scale. In Ilhéus, the neutral assembly predominance suggests an effect of functional homogenization between habitats. Thus, the conservation value of cacao agroforestry to harbor species-rich communities and ecosystem functions relies on smallholder production with reduced farm management in a forested landscape. Finally, we emphasize that seed dispersers and insectivores should be the priority conservation targets in cacao systems.

3.
Ecology ; 100(6): e02647, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845354

RESUMO

Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data are not always available for many species at the local or regional scale, we are limited in our understanding of intra- and interspecies spatial morphological variation. Here, we present the ATLANTIC BIRD TRAITS, a data set that includes measurements of up to 44 morphological traits in 67,197 bird records from 2,790 populations distributed throughout the Atlantic forests of South America. This data set comprises information, compiled over two centuries (1820-2018), for 711 bird species, which represent 80% of all known bird diversity in the Atlantic Forest. Among the most commonly reported traits are sex (n = 65,717), age (n = 63,852), body mass (n = 58,768), flight molt presence (n = 44,941), molt presence (n = 44,847), body molt presence (n = 44,606), tail length (n = 43,005), reproductive stage (n = 42,588), bill length (n = 37,409), body length (n = 28,394), right wing length (n = 21,950), tarsus length (n = 20,342), and wing length (n = 18,071). The most frequently recorded species are Chiroxiphia caudata (n = 1,837), Turdus albicollis (n = 1,658), Trichothraupis melanops (n = 1,468), Turdus leucomelas (n = 1,436), and Basileuterus culicivorus (n = 1,384). The species recorded in the greatest number of sampling localities are Basileuterus culicivorus (n = 243), Trichothraupis melanops (n = 242), Chiroxiphia caudata (n = 210), Platyrinchus mystaceus (n = 208), and Turdus rufiventris (n = 191). ATLANTIC BIRD TRAITS (ABT) is the most comprehensive data set on measurements of bird morphological traits found in a biodiversity hotspot; it provides data for basic and applied research at multiple scales, from individual to community, and from the local to the macroecological perspectives. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching and educational activities.

4.
Proc Biol Sci ; 283(1824)2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26842573

RESUMO

Ecological communities that experience stable climate conditions have been speculated to preserve more specialized interspecific associations and have higher proportions of smaller ranged species (SRS). Thus, areas with disproportionally large numbers of SRS are expected to coincide geographically with a high degree of community-level ecological specialization, but this suggestion remains poorly supported with empirical evidence. Here, we analysed data for hummingbird resource specialization, range size, contemporary climate, and Late Quaternary climate stability for 46 hummingbird-plant mutualistic networks distributed across the Americas, representing 130 hummingbird species (ca 40% of all hummingbird species). We demonstrate a positive relationship between the proportion of SRS of hummingbirds and community-level specialization, i.e. the division of the floral niche among coexisting hummingbird species. This relationship remained strong even when accounting for climate, furthermore, the effect of SRS on specialization was far stronger than the effect of specialization on SRS, suggesting that climate largely influences specialization through species' range-size dynamics. Irrespective of the exact mechanism involved, our results indicate that communities consisting of higher proportions of SRS may be vulnerable to disturbance not only because of their small geographical ranges, but also because of their high degree of specialization.


Assuntos
Distribuição Animal , Aves/fisiologia , Ecossistema , Magnoliopsida/fisiologia , Simbiose , Animais , América Central , Clima , América do Norte , América do Sul
5.
Biosci. j. (Online) ; 30(5): 1587-1587, sept./oct. 2014. tab, ilus
Artigo em Português | LILACS | ID: biblio-946714

RESUMO

Na Chapada Diamantina, porção norte da Cadeia do Espinhaço, ainda é escasso o conhecimento sobre as comunidades de beija-flores e das plantas que visitam, sendo que os registros disponíveis são de áreas de campo rupestre e caatinga. Este estudo objetivou identificar a troquilofauna de uma área de cerrado ralo da Chapada Diamantina, Bahia, reportando sua sazonalidade e interações agonísticas, além das espécies de plantas que exploram, considerando seus atributos florais e sua fenologia de floração. Os dados foram coletados no município de Mucugê, de outubro de 2005 a agosto de 2006, durante expedições bimestrais em área de cerrado ralo, denominado localmente como "Gerais de Mucugê" (13º 07'15,7"S; 41º 34'53,6"W). Foram registradas quais as espécies de beija-flores ocorrem, sua sazonalidade, suas interações agonísticas inter e intraespecíficas, quais as espécies de plantas visitam, seus atributos florais (morfometria floral, tipo e coloração da flor, concentração de néctar) e seu período de floração. Oito espécies de beija-flores foram registradas: Phaethornis pretrei, Chlorostilbon lucidus, Heliactin bilophus, Eupetomena macroura, Colibri serrirostris, Calliphlox amethystina, Chrysolampis mosquitus e Anopetia gounellei - as três primeiras, residentes na área. Apenas 21 interações agonísticas foram observadas, nas quais Heliactin bilophus esteve envolvido em 12 delas. Esta espécie de beijaflor forrageou o maior número de espécies de plantas (nove espécies), das quais cinco espécies são ornitófilas, e foi considerada a espécie organizadora desta guilda de polinizadores nesta área. Onze espécies de plantas foram utilizadas por beija-flores, das quais sete ornitófilas. O padrão fenológico de floração estimado foi sequencial e contínuo, garantindo recursos aos beija-flores residentes durante todo o ano.


In the northern portion of the Espinhaço Range, records of hummingbird communities and their plants are restricted to rocky fields ("campo rupestre") and dry lands ("caatinga") habitats. This study aimed to identify the flower resources used by hummingbirds in a savannah area at Chapada Diamantina. With this purpose we described hummingbirds' seasonality and agonistic interactions, and floral attributes and flowering phenology of their plant resources. The surveys were carried out at "Gerais de Mucugê" (13º 07'15,7"S; 41º 34'53,6"W) in Chapada Diamantina, municipality of Mucugê, state of Bahia, Brazil. Twelve expeditions were undertaken on a bi-monthly basis between October, 2005 and August, 2007 at an open savannah area. Field activities included observations of hummingbird species, their behavior, and the frequency of their visits; as well as the plant species they visited, their floral attributes, size of corollas, and the flowering period. Eight species of hummingbirds were recorded: Phaethornis pretrei, Chlorostilbon lucidus, Heliactin bilophus, Eupetomena macroura, Colibri serrirostris, Calliphlox amethystina, Chrysolampis mosquitus and Anopetia gounellei - the first three species were residents. We observed 21 agonistic interactions, in which Heliactin bilophus was involved in 12 of them. This species of hummingbird visited the largest number of plant species (nine species), most of which were considered ornithophilous (five species), and it was considered the organizer of the pollinator's guild of the study area. Eleven species of plants were used by hummingbirds, of which seven were considered ornithophilous. The plant community presented a continuous flowering, providing year-round resource for resident hummingbirds.


Assuntos
Plantas , Aves , Pradaria , Flores
6.
J Ethnobiol Ethnomed ; 10: 55, 2014 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25012812

RESUMO

BACKGROUND: Studies on popular names of birds help to understand the relationship between human beings and birds and it also contributes to the field of ornithology. METHODS: This study aims to register the ethnotaxonomy of birds in the village of Pedra Branca, Santa Teresinha municipality, Bahia State, Brazil, by cataloguing and identifying their popular names, besides understanding the ethnoclassification system of local bird species. The ethno-ornithological data were obtained by means of semi-structured open interviews, and projective tests. RESULTS: We interviewed 48 residents and, in order to identify species, we chose five informants with a more detailed knowledge on local avifauna. We registered 139 common names, distributed into 108 ethnospecies and 33 synonyms, referring to 117 species. Nomenclatural criteria more frequently used were vocalization and coloring patterns. Following Berlin's principles of ethnobiological classification, three hierarchical levels were registered: life form, generic and specific, with three types of correspondence between Linnaean and folk classification systems. The bird life form ("pássaro" in Portuguese) was associated only to wild species. CONCLUSIONS: The ethno-ornithological research in Pedra Branca Village has contributed with new information on popular nomenclature of birds and their etymology, showing that folk knowledge on birds is conveyed within the community.


Assuntos
Aves/classificação , Animais , Brasil , Etnologia
7.
Biosci. j. (Online) ; 29(5): 1328-1338, sept./oct. 2013. ilus
Artigo em Português | LILACS | ID: biblio-946939

RESUMO

O presente estudo investigou a fenologia de floração, a biologia floral e os visitantes florais de Calathe acrocata. Os dados foram coletados no sub-bosque de um fragmento de Mata Atlântica no município de Igrapiúna, Bahia. Expedições mensais ocorreram de julho de 2009 a agosto de 2011. Mensalmente foram registrados dados da fenologia de floração de C. crocata. Foram obtidos dados de morfometria floral, de volume e concentração de néctar, além de registrado os atributos florais de C. crocata. As espécies de beija-flores visitantes florais foram registradas durante observações indivíduo-focal em plantas floridas, da aurora ao crepúsculo, determinando a frequência e o comportamento de forrageio. Testes de polinização natural e autopolinização foram realizados, além da eficiência na liberação do estilete. A floração desta espécie é anual e tem duração intermediária, possuindo correlação negativa com a temperatura. Calatheacrocata é uma espécie ornitófila; suas flores são tubulosas, com corola amarela, com comprimento médio de 24,3mm e abertura de 2,6mm. O néctar tem concentração média de 21% de açúcares, com volume médio produzido de 9,4µl. As flores foram visitadas legitimamente por quatro espécies de beija-flores, com frequência de 0,69 visitas por inflorescência/hora, sendo Phaethornis ruber eficiente no disparo do gatilho. O principal vetor de pólen de C. crocata foi Phaethornis ruber. Calathea crocata é uma espécie alógama e não se autopoliniza espontaneamente: somente houve produção de frutos no teste de polinização natural. Características mais pontuais, como a redução do gatilho, presentes nessa espécie, podem ser um indício da evolução da melitofilia para a ornitofilia, já observada na família Marantaceae, porém ainda pouco evidenciada no gênero.


The study goals were to investigate the flowering phenology, the floral biology, and the floral visitors of Calathea crocata. The data was collected in an understory fragment of Atlantic Forest at Igrapiúna city, state of Bahia. Field expeditions were conducted by month from July 2009 to August 2011. Every month flowering phenology data was documented. Besides floral morphometry, volume and concentration of nectar data, the floral attributes of C. crocata were collected. Hummingbird species that visited the plant was registered by focal observations in breeding plants from sunrise to sunrise, establishing the frequency and forage behavior. Natural pollination and self-pollination tests were conducted, in addition to trigger efficiency. The breeding season is annual, and has intermediate duration, being negatively correlated with the temperature. Calathea crocata is an ornithophilous species; its flowers are tubular, with yellow corollas of 24,3mm of length average, and 2,6mm of aperture average. The nectar has a sugar's concentration average of 21%, and a volume's average production of 9,4 µl. The flowers were visited legitimately by four hummingbird species. The visits frequency was 0,69 visits per inflorescence/hour, all of them were able to release the trigger. Phaethornis ruber was the mainly pollen vector of C. crocata. Calathea crocata is an allogamous species, and is not capable of spontaneous selfpollination: just the natural pollination test produced fruits. More specific features, as the trigger reduction, visible in this species, can be an evolutionary evidence from melitophily to ornithophily already seen in Marantaceae family, but not too noted on the genre.


Assuntos
Aves , Marantaceae , Flores , Floresta Úmida
8.
PLoS One ; 6(10): e25891, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21998716

RESUMO

Large-scale geographical patterns of biotic specialization and the underlying drivers are poorly understood, but it is widely believed that climate plays an important role in determining specialization. As climate-driven range dynamics should diminish local adaptations and favor generalization, one hypothesis is that contemporary biotic specialization is determined by the degree of past climatic instability, primarily Quaternary climate-change velocity. Other prominent hypotheses predict that either contemporary climate or species richness affect biotic specialization. To gain insight into geographical patterns of contemporary biotic specialization and its drivers, we use network analysis to determine the degree of specialization in plant-hummingbird mutualistic networks sampled at 31 localities, spanning a wide range of climate regimes across the Americas. We found greater biotic specialization at lower latitudes, with latitude explaining 20-22% of the spatial variation in plant-hummingbird specialization. Potential drivers of specialization--contemporary climate, Quaternary climate-change velocity, and species richness--had superior explanatory power, together explaining 53-64% of the variation in specialization. Notably, our data provides empirical evidence for the hypothesized roles of species richness, contemporary precipitation and Quaternary climate-change velocity as key predictors of biotic specialization, whereas contemporary temperature and seasonality seem unimportant in determining specialization. These results suggest that both ecological and evolutionary processes at Quaternary time scales can be important in driving large-scale geographical patterns of contemporary biotic specialization, at least for co-evolved systems such as plant-hummingbird networks.


Assuntos
Biodiversidade , Aves , Mudança Climática , Plantas , Chuva , Animais , Geografia
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