52 resultados para Life history. MARK. Population parameters. Neotropical birds


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The poorly known Mimosa splendida Barneby has been rediscovered in the Chapada dos Veadeiros, Brazil, 105 years after its single record in 1895. Data on its habitat description, demography, reproductive parameters, and geographic range are presented. Preliminary results suggest that the rarity of M. splendida in herbarium collections is associated with a narrow geographic range, and a specialized habitat preference on rocky slopes.

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OBJECTIVE: To describe the demographic profile, social functioning, and quality of life of a population of long-stay care patients in a psychiatric hospital. METHODS: A study was carried out in Porto Alegre, Southern Brazil, in 2002. A total of 584 (96%) long-stay patients were assessed by means of the following instruments: the World Health Organization Quality of Life, the Social Behavior Schedule, the Independent Living Skills Survey, the Brief Psychiatric Rating Scale and another instrument for assessing disability (Questionnaire for Assessing Physical Disability). RESULTS: The average hospital stay was 26 years (SD: 15.8) and 46.6% of inpatients had no physical disability. Patients had their social functioning skills and autonomy largely impaired. Few of them (27.7%) answered the instrument for assessing quality of life, and showed significant impairments in all domains. The Brief Psychiatric Rating Scale evidenced a low prevalence of positive symptoms in this population. CONCLUSIONS: The institutionalized population studied presented significantly impaired social functioning, autonomy, and quality of life. These aspects need to be taken into consideration while planning for their deinstitutionalization.

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The population dynamics and the prevalence of chagasic infection of 352 dogs living in 108 rural houses infested by triatomines were studied. The region was divided into three sections according to increasing distances to an urban area. Each animal was identified by means of its particular characteristics and built, and its owners gave information about its habits. By means of xenodiagnosis, serology and ECG studies, prevalences of infection, parasitological-serological correlation, percentage of altered electrocardiographic outlines and percentage of houses with parasitemic dogs, were determined. The rural area showed a characteristic T. cruzi infection pattern and differences in the canine population parameters with respect to the other areas were observed: a higher proportion of puppies than adult dogs, a more sedentary population, higher prevalences of infection, as measured by xenodiagnosis, in dogs, and the highest proportion of bedroom insects infected with T. cruzi. It is assumed that the sedentary characteristics of the human population in that rural area impinge in the blood offer to the triatomine population, and the high percentage of parasitemic dogs of the area, contribute to the rise of "kissing ougs" infected with T. cruzi found in bedrooms.

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Few studies have been conducted to verify how the structure of the forest affects the occurence and abundance of neotropical birds. Our research was undertaken between January 2002 and July 2004 at the Reserva Ducke, near Manaus (02º55',03º01'S; 59º53',59º59'W) in central Amazonia, to verify how the forest structure affects the occurrence and abundance of two bird species: the Plain-brown Woodcreeper Dendrocincla fuliginosa and the White-chinned Woodcreeper Dendrocincla merula. Bird species occurrence was recorded using lines of 20 mist-nets (one sample unit), along 51 1-km transects distributed along 9 pararel 8 km trails covering an area of 6400 ha. Along these transects, we placed 50 x 50m plots where we recorded forest structure components (tree abundance, canopy openness, leaf litter, standing dead trees, logs, proximity to streams, and altitude). We then related these variables to bird occurence and abundance using multiple logistic and multiple linear regression models, respectively. We found that D. fuliginosa frequently used plateau areas; being more abundant in areas with more trees. On the other hand, D. merula occurred more frequently and was more abundant in areas with low tree abundance. Our results suggest that although both species overlap in the reserve (both were recorded in at least 68% of the sampled sites), they differ in the way they use the forest microhabitats. Therefore, local variation in the forest structure may contribute to the coexistence of congeneric species and may help to maintain local alpha diversity.

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Density-dependent responses are an important component of the organism life-history, and the resource allocation theory is a central concept to the life-history theory. When resource allocation varies due to environmental changes, a plant may change its morphology or physiology to cope with the new conditions, a process known as phenotypic plasticity. Our study aimed to evaluate how plant density affects Eichhornia crassipes allocation patterns. A total of 214 individuals in high and low density were collected. The density effect was observed in all plant traits examined including biomass accumulation. All traits of E. crassipes demonstrated higher values in high density conditions, except for biomass of leaves. Density exhibited a high influence on vegetative traits of E. crassipes, but did not influence allocation pattern, since a trade-off among the vegetative traits was not found. The morphological plasticity and the absence of trade-offs were discussed as strategies to overcome neighbor plants in competition situations. In high density conditions, there were clear changes in the morphology of the plants which probably allows for their survival in a highly competitive environment.

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Eight root-knot nematode forms are known to occur in Brazil, namely Meloidogyne exigua, M. incognita, M. j. javanica, M. j. bauruensis, M. inornata, M. hapla, M. arenaria arenaria and M. coffeicola. After presenting a historical resume of the root-knot disease, as well as observations on symptoms, distribution and spread, and life history of the nematodes, a study of the morphological characters used in identification of species is made, a key for separating the forms referred to above being also prepared. As no information on host plants of the coffee root-knot nematode (M. exigua) was available, a few tests were performed, as an attempt to infect several plant species. Pepper (Capsicum annuun) was the only plant attacked by M. exigua, having failed all attempts to infect nine other plants, including tomato var. Rutgers. M. exigua incited formation of galls on roots of cucumber, but no adult female was found in the tissue. In a final chapter dealing with control, a review of all methods available is presented.

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We studied life history traits of females of the lizard Eurolophosaurus nanuzae (Rodrigues, 1981), an endemic species of rock outcrop habitats in southeastern Brazil. During October 2002 and 2003 we sampled three populations in sites that encompass the meridional portion of the geographic range of the species. Clutch size varied from one to three eggs, with most females carrying two eggs. Clutch size did not vary among populations, but was correlated to female body size. Only larger females produced clutches of three eggs. Females of the small-sized E. nanuzae produce eggs as large as those of medium-sized tropidurids, thus investing a considerable amount of energy to produce clutches resulting in high values of relative clutch mass.

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ABSTRACT Male gladiator frogs of Hypsiboas Wagler, 1830 build nests on available substrate surrounding ponds and streams where female spawn eggs during the breeding period. Although gladiator frogs seem to show plasticity in the way they construct their nests, there is no study reporting if these species present preferences about microhabitat conditions for nest-building (mainly under subtropical climate). Predation pressure and environmental conditions have been considered major processes shaping the great diversity of reproductive strategies performed by amphibians, but microhabitat conditions should explain where to build a nest as well as how nest looks. This study aimed to test nest site selection for nest-building by Hypsiboas faber(Wied-Neuwied, 1821), determining which factors are related to nest site selection and nest features. The survey was conducted at margins of two permanent ponds in Southern Brazil. Habitat factors were evaluated in 18 plots with nest and 18 plots in the surrounding without nest (control), describing vegetation structure and heterogeneity, and substrate characteristics. Water temperature was measured inside the nest and in its adjacency. Nest features assessed were area, depth and temperature. Habitat characteristics differed between plots with and without nest. Microhabitat selected for nest-building was characterized by great vegetation cover and height, as well as shallower water and lower cover of organic matter in suspension than in plots without nest. Differences between temperature inside nest and in its adjacency were not observed. No relationship between nest features and habitat descriptors was evidenced. Results revealed that Hypsiboas faber does not build nests anywhere. Males seem to prefer more protected habitats, probably avoiding predation, invasion of conspecific males and inclement weather. Lack of differences between temperature inside- and outside-nest suggest that nest do not improve this condition for eggs and tadpole development. Nest architecture was not related to habitat characteristics, which may be determined by other factors, as nest checking by females before amplexus. Nest site selection should increase offspring survival as well the breeding success of Hypsiboas faber.

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The A. and his co-workers captured in trips in the hinterland of Brazil more tham 17.000 flebotomi from which 35 are new ones, 11 discribed by, him in previous papers. The A. found these insects in groups of species living in different habitats, some ones of them not yet known: ondoors, or outdoors attracted by light or animal baits, without Shannon’s trap, in great or small caves, in the jungle in tree’s holes, holes in stones, holes in the soil habited by animals like armadillos, pacas (Aguti paca), wild rats, cururú toad (Bufo sp.). He observed the life history of 13 species: Flebotomus longipalpis Lutz& Neiva, 1912, Flebotomus intermedius Lutz & Neiva, 1912, Flebotomus avellari Costa Lima, 1932, Flebotomus aragãoi costa Lima, 1932, Flebotomus lutzianus Costa Lima, 1932, Flebotomus limai fonseca, 1935, Flebotomus rickardi Costa Lima, 1936, Flebotomus dasipodogeton Castro, 1939, Flebotomus oswaldoi n. sp., Flebotomus villelai n. sp., Flebotomus triacanthus n. sp., Flebotomus longispinus n. sp. And flebotomus travassosi n. sp. He describes the male of 24 n. sp., explaining the differential diagnose of group or nearly allied species. He inclued F. rooti n. sp. And F. hirsutus n. sp. In the sub-genus Shannonomyia. The first one, very allied to F. davisi Root is different from it, for presenting in the dorsal side of the abdomen bristles and not scales and to have the median claspers longer than his inner appendage and F. hirsutus quite different from the others which show 3 spines on distal segment of the upper clasper and for being the only one who presents the bristles of inner appendage of median clasper longer than it. Only the females of F. amazonensis Root and f. chagasi Costa Lima, are known and then it is possible that they belong to one of the species of this sub-genus from whom only the male have been described. F. choti Floch & Abonnenc, captured also at Pará, F. triacanthus n. sp. F. trispinosus n. sp. And F. equatorialis n. sp. Are very related and to this group the A. proposes the same of Pressatia as sub-genus in honor to whom demonstrated the medical importance of the flebotomi, considering F. triacanthus as the type specie of this sub-genus. In this sub-genus the V papal joint is very long, longer than III + IV, the antennae with geniculated spines without posterior outgrowth. At the genitalia the basal segment of the upper clasper presents two types of bristles ou the inner face, arranged in tuft; the distal segment with 3 spines and 2 thin bristles something difficult to see one of them situated near the apical spine and the other on the base of tubercle where the median spine is articulated; the median clasper is unarmed and compressed; the inferior clasper is also unarmed and longer than de basal segment of the upper clasper; the pompeta is longer than the basal segment of the upper clasper. Following it is presented a key for the determination of the males of the four species of this sub-genus. F. micropygus n. sp., F. minasensis n. sp. e F. dandrophylus n. sp., f. shannoni, F. monticolus, F. pestanai, F. lanei and F. cayenensis constitute a group with many similars characters. F. micropygus is the only American species who present α smaller than β and for that reason and others is allied to. F. minuts and others related species, but presents two terminal spines on the distal segment of the upper clasper. F. micropygus and f. minasensis are quite different because they have very small genitalia, smaller than their heads. F. dendrophylus presents on the median clasper a naked area near the apex and for this and others characters is different from the others of the group. F. flaviscutellatus n. sp., F. oliverioi, F. intermedius and whithmani, are very allied but the first one can be very easily distinguished because it’s scutellum is light. Flebotomus barrettoi n. sp., F. coutinhoi n. sp., F. aragãoi, F. brasiliensis, F. lutzianus, F. texanus, F. pascalei, F. atroclavatus and F. tejeraae are very allied forming a natural group. The two last ones are not well known but the A. A. who have studied them described very long clipeus so long as the head and for that reason can be distinguished from all the others included the two new ones. F. coutinhoi is the only one who presents the apecis of the penis filaments twisted. F. barrettoi n. sp., can be distinguished from aragãoi, texamus and coutinhoi by the length of the penis filaments and from atrocavatus, tejeraae, lutzianus and brasiliensis by the arrangement of the spines of distal segment of the upper clasper. Flebotomus ubiquitalis n. sp., F. auraensis n. sp., F. affinis and F. microps e F. antunesi have many common characters. F. microps n. sp., can be distinguished from any one by the size of the eyes and the presence od well developed genae. This species and other new species are different from F. antunesi by the arrangement of the spines of the distal segment of the upper clasper of the latter. F. ubiquitalis n. sp. can be distinguished from others by the figure of the median clasper. F. auraensis n. sp. Can be distinguished from F. affinis n. sp. By the tuft hairs on the inner face of the basal segment and by arrangement of the spines of the sital segment of the upper clasper. Flebotomus brachipygus n. sp. Seemed to be F. rostrans, specie not well known, by the characters of the genitalia but can not be identified to her by the clypeus size and the palpi’s characters. Flebotomus costalimai, n. sp., f. tupynambai n. sp., and f. castroi Barreto & Coutinho, 1941, are very allied species and the A. proposes to included them the new sub-genus Castromyia, in honor to Dr. G. M. de Oliveira Castro, appointing like typespecies F. castroi with the V joint longer than III + IV; antennae with geniculated spines without posterior prolongation. Genitalia: the basal segment of the upper clasper with a tuft of hairs and the distal segment with 4 spines, one of them at the apex and near it a thin and straight bristle difficult to see; the median clasper with one spinous hair isolated...

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The A. describes the life history of Flebotomus longispinus Mangabeira, 1942, the ova, the larvae of the first, second and fourth stages and the female. For lack of material the larval third stage and the puppae were not described.

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The A. describes the life history of Flebotomus (Brumptomyia) travassosi Mangabeira, 1942. The paper deals with the morphology of the eggs, the larvae in all stages, the pupae and the female. Also gives the differences between the 3 known species of that subgenus (avellari, travassosi and guimarãisi) pointing out the characters in common, principally the presence of only two caudal hairs in all stages. The pupae do not present specifical characters.

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Aedes albifasciatus is a flood water mosquito ocurring in the southern countries of South America. It is a competent vector of the Western Equine Encephalitis (WEE) and causes important losses on milk and beef production in central Argentina. Field work was carried out from December 1990 to March 1993, on a monthly basis during the dry season and biweekly during the rainy season. Larvae were collected using the 'dipping' technique and females with CDC traps baited with CO2. Field collected larvae were used to build laboratory cohorts, from which basic population parameters were estimated. Eggs survived up to six months on dry soil, although there was a linear decrease of viability with time. At 23ºC, larval development time was around nine days, and all adults emerged within one week. The estimation of larval development in the laboratory seems to be very near the development on the field, as larvae have been collected on average eight days after a rainfall. Egg to adult survival was 83%, with the highest mortality on fourth larval instar (6%). In the laboratory studies, sex proportion among the adults was 1:1, females lived longer than males (median 13 and five days, respectively), and adult survival pattern showed a constant number of individuals dying per unit time. Field collected females layed an average of 84 eggs per batch, and completing up to five gonotrophic cycles, suggesting an estimated survival of up to 35-50 days.

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Experiments with Squamatoides trivitattus were carried out in two different controlled temperatures (16±1°C/50-60% RH and 27±1°C/70-80% RH). The viability of larvae and pupae at 27°C was 89.82% and 92.75% respectively. Larvae did not develop at 16°C. Larval development lasted for 20±4 hr, 16±8 hr and 60±7 hr for the first, second and third instars, respectively, completing a total of 96±6 hr. The mean pupal period lasted for 15.7±1.6 days. In longevity tables for the adults, life-expectancy for 50% of the colony submitted to 16°C was of 1.78 weeks for males and 2.42 for females. At 27°C a life-expectancy of 1.15 weeks for males and 0.78 week for females was recorded. The average life-spans for males and females at 16°C were 3.5±2.0 and 3.8±2.6 weeks, respectively, and 1.9±1.2 weeks for both sexes. At 27°C, the longevity recorded was of 2.1±1.3 weeks for males and 1.7±1.1 week for females.

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A statistical evaluation of the population dynamics of Panstrongylus geniculatus is based on a cohort experiment conducted under controlled laboratory conditions. Animals were fed on hen every 15 days. Egg incubation took 21 days; mean duration of 1st, 2nd, 3rd, 4th, and 5th instar nymphs was 25, 30, 58, 62, and 67 days, respectively; mean nymphal development time was 39 weeks and adult longevity was 72 weeks. Females reproduced during 30 weeks, producing an average of 61.6 eggs for female on its lifetime; the average number of eggs/female/week was 2.1. Total number of eggs produced by the cohort was 1379. Average hatch for the cohort was 88.9%; it was not affected by age of the mother. Age specific survival and reproduction tables were constructed. The following population parameters were evaluated, generation time was 36.1 weeks; net reproduction rate was 89.4; intrinsic rate of natural increase was 0.125; instantaneous birth and death rates were 0.163 and 0.039 respectively; finite rate of increase was 1.13; total reproductive value was 1196 and stable age distribution was 31.2% eggs, 64.7% nymphs and 4.1% adults. Finally the population characteristics of P. geniculatus lead to the conclusion that this species is a K strategist.

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A snail-conditioned water experiment was conducted in Pseudosuccinea columella to test the possible role of a chemical interaction between snails on the diminished growth and fecundity rates found for snails raised in pairs compared to those raised in complete isolation. The results permit to discard the hypothesis of an inhibition of growth and reproduction between snails due to factors released into the water.