ABSTRACT
Abstract Nasal mites are commonly found in hummingbirds (Apodiformes). In most cases, endoparasitic mites were reported to parasitize the respiratory system, particularly the anterior nasal chambers, larynx, trachea, lungs, and the air and conjunctival sacs. However, some mites are only carried by hummingbirds, because flowers serving as a nutrient source for these small mites, such as for Apodiformes, a tropical nectar-feeding in their natural habitat. From August 2012 to May 2014, humminbirds were captured using mist nets, and examined for the presence of nasal mites (identified according to specific keys) in the Pantanal, and Cerrado biomes, from the Mato Grosso state, midwestern Brazil. Overall, 76 Apodiform specimens, from the Trochilidae family were captured, and 20 female nasal mites, identified as being from the Rhinoseius genus, were collected from eight hosts (10.5%), of the following species: Amazilia fimbriata, Amazilia versicolor, Eupetonema macroura, and Thalurania furcata. The Rhinoseius spp. has been reported on, in many ecosystems in the Americas, including Brazil, however, this is the first report on Apodiformes from the Pantanal biome. Phoretic mites are not responsible for direct damage to the population of Apodiformes, as they are not pathogenic. However, they compete for food with hummingbirds and decrease the quantity of food available in the environment. They also affect the reproductive dynamics of plants, feed on pollen, and interfere with the intricacies of the biodiversity where they live.
Resumo Os ácaros nasais são comumente encontrados em beija-flores (Apodiformes). Na maioria dos casos, os ácaros foram relatados como endoparasitas, parasitando o sistema respiratório, particularmente as câmaras nasais anteriores, a laringe, a traqueia, os pulmões e os sacos aéreos e conjuntivais. No entanto, alguns ácaros são transportados apenas por beija-flores, pois flores servem como fonte de nutrientes para esses pequenos ácaros, assim como para Apodiformes tropicais alimentados de néctar em seu habitat natural. De agosto de 2012 a maio de 2014, beija-flores foram capturadas com redes de neblina e examinadas quanto à presença de ácaros nasais (identificados de acordo com chaves específicas) nos biomas Pantanal e Cerrado, no estado do Mato Grosso, Centro-Oeste do Brasil. No total, 76 exemplares Apodiformes da família Trochilidae foram capturados e 20 fêmeas de ácaros nasais, identificados como pertencentes ao gênero Rhinoseius, foram coletados de oito hospedeiros (10,5%), das seguintes espécies: Amazilia fimbriata, Amazilia versicolor, Eupetonema macroura e Thalurania furcata. Rhinoseius spp. foi relatado em muitos ecossistemas nas Américas, incluindo o Brasil, no entanto, este é o primeiro relato em Apodiformes do bioma Pantanal. Os ácaros foréticos não são responsáveis por danos diretos à população de Apodiformes, pois não são patogênicos. No entanto, eles competem por comida com beija-flores e diminuem a quantidade de comida disponível no ambiente. Eles também afetam a dinâmica reprodutiva das plantas, se alimentam de pólen e interferem nas interações da biodiversidade em que vivem.
Subject(s)
Animals , Female , Mites , Birds , Brazil , Ecosystem , Plant NectarABSTRACT
In tropical trees, forest fragmentation has been shown to affect mating and gene flow patterns. Mobile dispersal vectors should be less sensitive to fragmented landscapes and may ameliorate the genetic effects of forest fragmentation on plant populations. To test this hypothesis, we analyzed gene flow patterns in Symphonia globulifera, a tropical tree species with highly mobile pollinators and seed dispersers in the Osa Peninsula in southern Costa Rica. We used microsatellites to study genetic diversity and realized gene flow patterns between a continuous forest and a forest fragment. We found high levels of genetic diversity in adults and seedlings at both sites. Parentage analyses suggest near-neighbor matings and frequent long-distance gene flow events. Half the progeny beneath an adult was not sired by that tree and the majority of established seedlings were the result of long-distance gene dispersal. Gene flow from the forest into the fragment was more common than from the fragment into the continuous forests. Despite long distance gene flow events, seedling spatial genetic structure was stronger and extended further in the forest fragment likely due to limited seed dispersal. We conclude that fragmentation affects gene flow in this tropical tree and may compromise its genetic diversity in forest fragments even for a species with mobile pollen and seed vectors.
En árboles tropicales se ha demostrado que la fragmentación del bosque afecta los patrones de apareamiento y reduce el flujo génico. Las especies forestales cuyos dispersores y polinizadores son capaces de moverse largas distancias sobre ambientes alterados, serán menos sensibles a los efectos de la fragmentación y podrán intercambiar genes regularmente entre fragmentos. Para probar esta hipótesis, en la Península de Osa en el sur de Costa Rica, estudiamos los patrones de flujo génico de Symphonia globulifera, una especie de árbol tropical con polinizadores y dispersores de semillas altamente móviles. Utilizamos microsatélites para estudiar la diversidad genética y los patrones de flujo génico entre un bosque continuo y un fragmento de bosque. Encontramos altos niveles de diversidad genética tanto en adultos como en plántulas. Los análisis de parentesco indican apareamiento entre vecinos cercanos, sin embargo el flujo génico a larga distancia es frecuente. La mitad de la progenie debajo de un adulto no es engendrada por ese árbol y la mayoría de las plántulas establecidas son el resultado del flujo génico a larga distancia. El flujo de genes desde el bosque continuo hacia el fragmento era más frecuente que el movimiento inverso. A pesar del flujo génico a larga distancia, hay diferencias en frecuencias alélicas entre plántulas y la estructura espacial era más fuerte y se extendía a mayor distancia en el fragmento, probablemente por una dispersión limitada de semillas. Concluimos que la fragmentación afecta los patrones de flujo génico en esta especie de árbol tropical y puede afectar su diversidad genética en paisajes fragmentados, inclusive para una especies con polinizadores y dispersores con alta movilidad.
ABSTRACT
AbstractPitcairnioideae is the second most diverse subfamily of bromeliads (Bromeliaceae), a group exclusive to tropical regions of the New World. Pitcairnioid bromeliads have floral traits assumed to promote outcrossing through biotic pollination systems; however, the reproductive biology of most of the species of this group has not been documented. Pitcairnia heterophylla is an epiphytic (seldom saxicolous) bromeliad occurring from Southern Mexico, into the Northern Andes. We studied the pollination and breeding system of P. heterophylla in an epiphytic population at a mountain forest in Costa Rica from January to April 2013. We performed hand pollination experiments (agamospermy, autonomous self-pollination, hand self-pollination and hand cross-pollination) on 89 flowers from 23 individuals (3-6 flowers per individual) in 2013 flowering season. Nectar production was measured on 18 unvisited flowers of six individuals with a hand-held refractometer. Simultaneously, floral visitors were recorded on eight individuals with trail cameras for a total of 918 hours (115 ± 52 hours per individual, mean ± SE). Under natural conditions, seed set (540.4 ± 55.2) was similar to manually selfed flowers (516.3 ± 41.5) and autonomously selfed flowers (521.1 ± 29.0), but lower to manually outcrossed flowers (670.2 ± 31.3). The flowers of P. heterophylla are self-compatible, capable of autonomous pollination, and non-agamospermous. Intrafloral self-pollination is facilitated by adichogamy and lack of floral herkogamy. The scentless red flowers of P. heterophylla with tubular corollas and nectar production suggested ornithophilic pollination which was confirmed by video recording of 46 hummingbird visits. The most common floral visitor was the short-billed hummingbird Lampornis calolaemus which accounted for 78 % of the visits. However, the visitation rate during the flowering season was low (0.6 visits per day per plant). Selfing in P. heterophylla might be explained as a mechanism of reproductive assurance and to reduce interspecific pollen flow with taxonomically unrelated plants.
ResumenLa subfamilia Pitcairnioideae es la segunda más diversa de las bromelias (Bromeliaceae), un grupo exclusivo de la región Neotropical. Las bromelias pitcairnioideas poseen rasgos florales que se asume promueven el exo-cruzamiento a través de sistemas de polinización biótica; sin embargo, la biología reproductiva de la mayoría de especies de este grupo no se ha documentado. Pitcairnia heterophylla es una bromelia epífita (raramente saxícola) que se encuentra en el sur de México, América Central y el norte de los Andes. Se estudió la polinización y el sistema de apareamiento de una población P. heterophylla en un bosque montano en Costa Rica entre enero y abril 2013. Se realizaron cuatro experimentos de polinización (agamospermia, auto-polinización espontánea, auto-polinización manual, exo-polinización manual) en 89 flores de 23 individuos (3-6 flores por individuo). Se cuantificó la producción de néctar de 18 flores en seis individuos con un refractómetro. Simultáneamente, se registraron los visitantes florales de ocho individuos en el campo con ayuda de cámaras trampa por un total de 918 horas (115 ± 52 horas por individuo, promedio ± ES). Bajo condiciones naturales la producción de semillas fue similar (540.4 ± 55.2) a la producción de las flores auto-polinizadas manualmente (516.3 ± 41.5) y las flores auto-polinizadas espontáneamente (521.1 ± 29.0), pero fue menor a las flores exo-cruzadas (670.2 ± 31.3). Las flores de P. heterophylla son auto-compatibles, con alta capacidad de polinización espontánea y sin capacidad de agamospermia. La auto-polinización intra-floral es facilitada por la ausencia de dicogamia y hercogamia floral. Las flores rojas, sin aroma, con corola tubular y con producción de néctar sugirieron polinización por ornitofilia, lo que se confirmó con el registro de 46 visitas por colibríes (Apodiformes: Trochilidae). El visitante floral más común fue Lampornis calolaemus (78 % de las visitas). A pesar de esto, la tasa de visitas durante el periodo de estudio fue baja (0.6 visitas por día por planta). La capacidad de autofecundación de P. heterophylla puede ser explicada como un mecanismo de aseguramiento reproductivo, así como para reducir el flujo de polen inter-específico de plantas taxonómicamente no relacionadas.
ABSTRACT
Abstract Nasal mites are commonly found in hummingbirds (Apodiformes). In most cases, endoparasitic mites were reported to parasitize the respiratory system, particularly the anterior nasal chambers, larynx, trachea, lungs, and the air and conjunctival sacs. However, some mites are only carried by hummingbirds, because flowers serving as a nutrient source for these small mites, such as for Apodiformes, a tropical nectar-feeding in their natural habitat. From August 2012 to May 2014, humminbirds were captured using mist nets, and examined for the presence of nasal mites (identified according to specific keys) in the Pantanal, and Cerrado biomes, from the Mato Grosso state, midwestern Brazil. Overall, 76 Apodiform specimens, from the Trochilidae family were captured, and 20 female nasal mites, identified as being from the Rhinoseius genus, were collected from eight hosts (10.5%), of the following species: Amazilia fimbriata, Amazilia versicolor, Eupetonema macroura, and Thalurania furcata. The Rhinoseius spp. has been reported on, in many ecosystems in the Americas, including Brazil, however, this is the first report on Apodiformes from the Pantanal biome. Phoretic mites are not responsible for direct damage to the population of Apodiformes, as they are not pathogenic. However, they compete for food with hummingbirds and decrease the quantity of food available in the environment. They also affect the reproductive dynamics of plants, feed on pollen, and interfere with the intricacies of the biodiversity where they live.
Resumo Os ácaros nasais são comumente encontrados em beija-flores (Apodiformes). Na maioria dos casos, os ácaros foram relatados como endoparasitas, parasitando o sistema respiratório, particularmente as câmaras nasais anteriores, a laringe, a traqueia, os pulmões e os sacos aéreos e conjuntivais. No entanto, alguns ácaros são transportados apenas por beija-flores, pois flores servem como fonte de nutrientes para esses pequenos ácaros, assim como para Apodiformes tropicais alimentados de néctar em seu habitat natural. De agosto de 2012 a maio de 2014, beija-flores foram capturadas com redes de neblina e examinadas quanto à presença de ácaros nasais (identificados de acordo com chaves específicas) nos biomas Pantanal e Cerrado, no estado do Mato Grosso, Centro-Oeste do Brasil. No total, 76 exemplares Apodiformes da família Trochilidae foram capturados e 20 fêmeas de ácaros nasais, identificados como pertencentes ao gênero Rhinoseius, foram coletados de oito hospedeiros (10,5%), das seguintes espécies: Amazilia fimbriata, Amazilia versicolor, Eupetonema macroura e Thalurania furcata. Rhinoseius spp. foi relatado em muitos ecossistemas nas Américas, incluindo o Brasil, no entanto, este é o primeiro relato em Apodiformes do bioma Pantanal. Os ácaros foréticos não são responsáveis por danos diretos à população de Apodiformes, pois não são patogênicos. No entanto, eles competem por comida com beija-flores e diminuem a quantidade de comida disponível no ambiente. Eles também afetam a dinâmica reprodutiva das plantas, se alimentam de pólen e interferem nas interações da biodiversidade em que vivem.
ABSTRACT
We present a case of a 71-year-old male Chamorro patient from Guam who presented with progressive supranuclear palsy (PSP)-Richardson’s syndrome. Considering his strong family history of parkinsonism and a PSP phenotype, he was clinically diagnosed with Guam parkinsonism-dementia complex (PDC). Magnetic resonance imaging (MRI) of the brain revealed prominent midbrain atrophy with preserved pontine volume, forming the ‘hummingbird’ sign, which has not been described before in Guam PDC. Molecular analysis of the chromosome 9 open reading frame 72 gene (C9orf72) showed only 6 GGGGCC repeats. We discuss the clinico-pathological similarities and differences between PSP and Guam PDC, and highlight the topography of neuropathological changes seen in Guam PDC to explain the appearance of the ‘hummingbird’ sign on MRI.
Subject(s)
Aged , Humans , Male , Atrophy , Brain , Chromosomes, Human, Pair 9 , Guam , Magnetic Resonance Imaging , Mesencephalon , Open Reading Frames , Parkinsonian Disorders , Phenotype , Supranuclear Palsy, ProgressiveABSTRACT
Floral mechanisms that ensure seed production via autogamy are more likely to occur in species growing in environments where pollination is scarce. Amasonia obovata was studied in the State of Mato Grosso-Brazil, from 2009 to 2012, to analyze the morphological and reproductive characteristics, aside from investigating the association of the reproductive success with the pollinator frequency and identity. The flowering and fruiting of A. obovata was concentrated in a period of five months during the rainy season. The dichogamy in flowers of A. obovata is not clearly defined, since the sexual functions were overlapped in the male and female phases. The species is self-compatible and not apomictic. The fruiting percentage obtained by hand self-pollination did not differ from cross-breeding (F = 0.74, P =0.39). In the observations from 2010 to 2012, a hummingbird (Thalurania furcata) legitimate visited 20-100% of the flowers in the male and female phases on different A. obovata plants. Due to the high frequency, this hummingbird was considered the single potential pollinator of the species. These findings show that a limited availability of pollinators may select for floral traits and plant mating strategies that lead to a system of self-fertilization.
Mecanismos florais que garantem produção de sementes via autogamia, são mais prováveis de ocorrer em espécies que crescem em habitats onde a polinização é escassa. Amasonia obovata foi estudada na região sudoeste do estado de Mato Grosso, durante os anos de 2009 a 2012, e o estudo teve por objetivo analisar as características morfológicas, morfométricas e reprodutivas, além de associar o sucesso reprodutivo à frequência de polinizadores. A. obovata concentrou a floração e frutificação em um período de cinco meses, durante a estação chuvosa. A dicogamia em flores de A. obovata não está claramente demarcada, já que as funções sexuais se sobrepõem nas fases masculina e feminina. A espécie é autocompatível e não apomítica. Os valores percentuais de frutificação obtidos na autopolinização manual não diferiram dos valores obtidos na polinização cruzada (F= 0,74; P=0,39). Em observações realizadas nos anos de 2010 a 2012, o beija-flor (Thalurania furcata) realizou de 20 a 100% de visitas legítimas às flores nas fases masculina e feminina, de diferentes indivíduos de A. obovata e, devido à sua frequência, foi considerado o potencial polinizador da espécie. Os resultados mostram que a limitada disponibilidade de polinizadores pode selecionar plantas de características florais e estratégias de reprodução que levam a um sistema reprodutivo autogâmico.
ABSTRACT
Infection with Helicobacter pylori cagA-positive strains is associated with gastroduodenal diseases. The CagA protein is injected into gastric epithelial cells and supposedly induces morphological changes termed the ‘hummingbird phenotype’, which is associated with scattering and increased cell motility. The molecular mechanisms leading to the CagA-dependent morphological changes are only partially known. The present study was carried out to investigate the effect of CagA variants on the magnitude of gastric epithelial cell morphological changes. Recombinant 3’ terminal domains of cagA were cloned and expressed in a gastric epithelial cell line and the hummingbird phenotype was quantifi ed by microscopy. The 3’ region of the cagA gene of Malaysian H. pylori isolates showed six sub-genotypes that differed in the structural organization of the EPIYA repeat sequences. The percentage of hummingbird cells induced by CagA increased with duration of transfection. The hummingbird phenotype was observed to be more pronounced when CagA with 4 EPIYA motifs rather than 3 or 2 EPIYA motifs was produced. The activity of different CagA variants in the induction of the hummingbird phenotype in gastric epithelial cells depends at least in part on EPIYA motif variability. The difference in CagA genotypes might infl uence the potential of individual CagAs to cause morphological changes in host cells. Depending on the relative exposure of cells to CagA genotypes, this may contribute to the various disease outcomes caused by H. pylori infection in different individuals.
ABSTRACT
The aim of this work was to observe and describe the feeding habits and available food resources of the swallow-tailed hummingbird, Eupetomena macroura. The study was carried out in a municipal park located in the city of Taubaté, in the state of São Paulo. The observations took place between December 2003 and October 2004, recording the following variables: 1) the plant species visited for feeding and territorial defense; 2) the kinds of food resources; and 3) the kinds of flight to procure and obtain food. E. macroura visited 12 plant species. For territorial defense, Mangifera indica was the most visited, whereas Malvaviscus arboreus was most visited for feeding. The foliage was the plant part that received the most frequent visits. In order to obtain nectar, the only species visited was M. arboreus; to obtain arthropods, the species most visited were Mangifera indica and Hymenaea stilbocarpa. In the dry season, the hummingbirds visited flowers, whereas in the rainy season they visited leaves to acquire food. The arthropod groups most frequently found on leafy branches were Homoptera and Psocoptera. Finally, the results of the type of flight analysis showed that flight used to capture food was more often observed than were flights to search for food. In conclusion, these observations suggest that E. macroura shows plasticity in feeding behavior, which can help it to persist in urban areas.
O objetivo deste trabalho foi observar e descrever o hábito alimentar do Beija-flor Tesourão, Eupetomena macroura. O estudo foi realizado em um parque municipal, situado na cidade de Taubaté, Estado de São Paulo. As observações ocorreram entre dezembro de 2003 e outubro de 2004, período em que foram observadas as seguintes variáveis: 1) as espécies de plantas visitadas para alimentação e defesa territorial; 2) o tipo de recurso alimentar; e 3) a freqüência de vôo para busca e obtenção de alimento. Foram registradas 12 espécies de plantas visitadas pelo E. macroura, visto que Mangifera indica e Malvaviscus arboreus foram as mais utilizadas para defesa territorial e para alimentação, respectivamente. O maior índice de flores visitadas foi observada para Malvaviscus arboreus. Mangifera indica e Hymenaea stilbocarpa foram as espécies que apresentaram maior freqüência de visita em folhas e ramos. Na estação seca, o beija-flor tesourão visitou flores para obtenção de alimento, já na estação úmida a maior parte do alimento foi adquirida entre folhas e ramos. Quando analisados as folhas e ramos visitados pelos indivíduos quanto à presença de artrópodes, os resultados obtidos indicaram que os grupos mais abundantes foram Homoptera e Psocoptera. Finalmente, pela análise do tipo de vôo, observou-se que o vôo que representa captura de alimento foi mais vezes observado do que aquele que é utilizado para procura de alimento. Os resultados sugerem uma flexibilidade trófica do E. macroura, fato que pode auxiliar na permanência da espécie em áreas urbanas.
Subject(s)
Animals , Feeding Behavior/physiology , Swallows/physiology , Brazil , Seasons , Urban PopulationABSTRACT
The pollination of Passiflora coccinea by the hummingbird Phaethornis superciliosus was studied in Central Amazon, Brazil. We hypothesized that a greater nectar secretion rate (NSR) increases the pollination success of single flowers through Ph. superciliosus visiting behavior. For control flowers, NSR was an increasing function of flower base diameter (FBD). The total number of Ph. superciliosus probes per flower was an increasing function of FBD. Additionally, deposition of pollen on stigmas increased with the cumulative number of Ph. superciliosus probes. Our results show that larger P. coccinea flowers secrete nectar at higher rates, are probed more times during each hummingbird visit and are more successful at pollination. This seems to be the first non-manipulative study describing such an effect of NSR on the pollination of single flowers in nature.
Estudamos a polinização de Passiflora coccinea por beija-flores Phaethornis superciliosus na Amazônia Central, Brasil. Nossa hipótese é que maiores taxas de secreção de néctar (TSN) aumentam o sucesso da polinização de flores individuais através do comportamento de visitas de Ph. superciliosus. Para flores controladas, a TSN foi uma função positiva do diâmetro da base da flor (DBF). O número total de visitas de Ph. superciliosus por flor foi uma função positiva do DBF. Adicionalmente, a deposição de pólen sobre os estigmas aumentou com o aumento do número acumulado de visitas de Ph. superciliosus. Nossos resultados indicam que flores maiores de P. coccinea secretam néctar em taxas mais altas, são visitadas mais vezes pelos beija-flores, e apresentam maior sucesso de polinização. Este parece ser o primeiro estudo não-manipulativo que descreve este efeito da TSN sobre o sucesso de polinização de flores individuais na natureza.