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41.
ADRIANE P. WANDENESS KAI H. GEORGE PAULO J. P. SANTOS 《Zoological Journal of the Linnean Society》2009,156(1):52-78
New species assignable to the formerly monotypic genus Echinopsyllus (Copepoda, Harpacticoida, Ancorabolidae) are described from the continental slope of Campos Basin off Brazil in the south‐western Atlantic. Echinopsyllus brasiliensis sp. nov. , Echinopsyllus nogueirae sp. nov. , and Echinopsyllus grohmannae sp. nov. differ from Echinopsyllus normani Sars, 1909 in the cephalothorax having two instead of three pairs of lateral processes, first pair of dorsal cephalothoracic processes being smaller than second pair, second pair of dorsal cephalothoracic processes branched, and segmentation and setation of the swimming legs. The discovery of new species of Echinopsyllus extends the distributional range of the genus to the southern hemisphere and is further evidence for the formerly unexpected wide genus‐level distribution of Ancorabolidae in the world's oceans. The phylogenetic position of Echinopsyllus within Ancorabolinae is discussed. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 52–78. 相似文献
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A. P. ALMEIDA H. D. ROSA O. S. PAULO E. G. CRESPO 《Journal of Zoological Systematics and Evolutionary Research》2002,40(2):57-64
The genetic structure and relationships of five populations of the Iberian group of Iberolacerta (sensu 6 ) were analysed by protein electrophoresis. In this study we confirmed the differentiation between the group of populations from Galicia/Cantabrian/S. Estrela versus the group of populations from de Spanish Central System, Gredos and Guadarrama that are included in the two different species by Arribas (Herpetozoa 9(1/2), 31–56, 1996; Russian J. Herpetol. 6, 1–22, 1999), Iberolacerta (I.) monticola and Iberolacerta (I.) cyreni, respectively. However, the differentiation level is not high enough to clearly prove their specific discrimination. On the other hand, we did not confirm the subspecific discrimination of the Gredos –Iberolacerta (I.) cyreni castiliana, and Guadarrama –Iberolacerta (I.) cyreni cyreni populations, proposed by 5 ). These two populations are genetically almost homogeneous. Interestingly, we found an unexpected high genetic similarity between the Galician and the Serra da Estrela populations, presently included into two different subspecies, Iberolacerta (I.) monticola cantabrica and Iberolacerta (I.) monticola monticola, respectively. Their genetic similarity is even higher than that between the populations of Galicia and the Cantabrian Mountains, which are both included in the same subspecies, cantabrica. This result suggests that the populations of Galicia and Serra da Estrela would have maintained contacts, possibly through the north of Portugal, until relatively recent times. Their separation is thus probably post‐glacial. Some evidence also points to the existence of relatively recent contacts between the population of Serra da Estrela and those of the Central System, particularly, with the neighbouring Peña de Francia population. With the cautions imposed by the reduced sample size of our analysis, the significant differentiation of the populations from Galicia and the Cantabrian Mountains allow us to suggest that this last population may not be the result of a recent expansion of the Galician population as 5 ) suggests, but, more likely, the result of a fragmentation process of a more ancient and wider north‐eastern distribution area of this group of rock‐lizards. 相似文献
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ALEXANDRA SÁ‐PINTO STUART J. E. BAIRD CATARINA PINHO PAULO ALEXANDRINO MADALENA BRANCO 《Biological journal of the Linnean Society. Linnean Society of London》2010,100(1):154-169
Previous studies have reported the occurrence of three differentiated mtDNA lineages within Patella rustica in the Mediterranean Sea. Two hypotheses have been proposed to explain these observations: (1) the maintenance of ancestral polymorphism within a single species; (2) the occurrence of cryptic species not identified previously. To distinguish between these hypotheses, we screened the genetic variability at nine allozyme loci, an intron from the α‐amylase gene and a mitochondrial gene for 187 individuals of P. rustica sampled from seven Mediterranean localities. Eight additional localities were screened for the last two markers to place the differentiated lineages in a clear geographic context. Our results demonstrate that the three mtDNA lineages correspond to three distinct nuclear genotype clusters and provide further details on their distribution: the cluster corresponding to the mtDNA lineage from the Atlantic and western Mediterranean extends as far as the south coast of Italy, whereas the remaining two clusters occur in sympatry in the eastern Mediterranean. One of the eastern Mediterranean clusters is highly differentiated and seems to be reproductively isolated from the codistributed form; we therefore suggest that it corresponds to a new species. The remaining two clusters are less differentiated and form a contact zone across south Italian shores. This three‐way contact zone constitutes an interesting model for the study of speciation in the marine realm. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100 , 154–169. 相似文献
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PAULO SILVEIRA JORGE PAIVA N. MARCOS SAMANIEGO 《Botanical journal of the Linnean Society. Linnean Society of London》2001,135(3):299-303
A new species, Arubis beirunu P. Silveira, Paiva & N. Marcos, from central Portugal is described and illustrated. A list of diagnostic differences between Arabis beirana and the closely related species A. sadina and A. stenocarpa is provided 相似文献
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YADVINDER MALHI LUIZ EDUARDO O. C. ARAGÃO DANIEL B. METCALFE ROMILDA PAIVA‡ CARLOS A. QUESADA§ SAMUEL ALMEIDA¶ LIANA ANDERSON PAULO BRANDO JEFFREY Q. CHAMBERS†† ANTONIO C. L. da COSTA‡‡ LUCY R. HUTYRA§§ PAULO OLIVEIRA‡‡ SANDRA PATIÑO¶¶ ELIZABETH H. PYLE AMANDA L. ROBERTSON†† LILIANE M. TEIXEIRA‡ 《Global Change Biology》2009,15(5):1255-1274
The allocation and cycling of carbon (C) within forests is an important component of the biospheric C cycle, but is particularly understudied within tropical forests. We synthesise reported and unpublished results from three lowland rainforest sites in Amazonia (in the regions of Manaus, Tapajós and Caxiuanã), all major sites of the Large‐Scale Biosphere–Atmosphere Programme (LBA). We attempt a comprehensive synthesis of the C stocks, nutrient status and, particularly, the allocation and internal C dynamics of all three sites. The calculated net primary productivities (NPP) are 10.1±1.4 Mg C ha−1 yr−1 (Manaus), 14.4±1.3 Mg C ha−1 yr−1 (Tapajós) and 10.0±1.2 Mg C ha−1 yr−1 (Caxiuanã). All errors bars report standard errors. Soil and leaf nutrient analyses indicate that Tapajós has significantly more plant‐available phosphorus and calcium. Autotrophic respiration at all three sites (14.9–21.4 Mg C ha yr−1) is more challenging to measure, with the largest component and greatest source of uncertainty being leaf dark respiration. Comparison of measured soil respiration with that predicted from C cycling measurements provides an independent constraint. It shows general good agreement at all three sites, with perhaps some evidence for measured soil respiration being less than expected. Twenty to thirty percent of fixed C is allocated belowground. Comparison of gross primary productivity (GPP), derived from ecosystem flux measurements with that derived from component studies (NPP plus autotrophic respiration) provides an additional crosscheck. The two approaches are in good agreement, giving increased confidence in both approaches to estimating GPP. The ecosystem carbon‐use efficiency (CUEs), the ratio of NPP to GPP, is similar at Manaus (0.34±0.10) and Caxiuanã (0.32±0.07), but may be higher at Tapajós (0.49±0.16), although the difference is not significant. Old growth or infertile tropical forests may have low CUE compared with recently disturbed and/or fertile forests. 相似文献
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Seed survival and dispersal of an endemic Atlantic forest palm: the combined effects of defaunation and forest fragmentation 总被引:3,自引:0,他引:3
MAURO GALETTI CAMILA I. DONATTI ALEXANDRA S. PIRES PAULO R. GUIMARÃES JR PEDRO JORDANO 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(1):141-149
About 45 palm species occur in the Atlantic forest of Brazil, and most of them are affected by loss of seed dispersers resulting from forest fragmentation and hunting. Here we report the effects of habitat loss and defaunation on the seed dispersal system of an endemic palm, Astrocaryum aculeatissimum . We evaluated seed removal, insect and rodent seed predation, and scatter-hoarding in nine sites, ranging from 19 ha to 79 000 ha. We report the seedling, juvenile and adult palm densities in this range of sites. Endocarps remaining beneath the parent palm had a higher probability of being preyed upon by insects in small, mostly fragmented and more defaunated sites. The frequency of successful seed removal, scatter-hoarding and consumption by rodents increased in the larger, less defaunated sites. Successful removal and dispersal collapsed in small (< 1000 ha), highly defaunated sites and frequently resulted in low densities of both seedlings and juveniles. Our results indicate that a large fraction of Atlantic forest palms that rely on scatter-hoarding rodents may become regionally extinct due to forest fragmentation and defaunation. Current management practices including palm extraction and hunting pressure have a lasting effect on Atlantic forest palm regeneration by severely limiting successful recruitment of prereproductive individuals. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 141–149. 相似文献
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ABSTRACT Nestling begging behaviour has long been seen as a signal by which nestlings solicit care from parents and most of the existing evidence provides some support for it being an honest signal. Begging is a multicomponent signal in which both sound and vision components are usually important. Although it is known that begging encodes information about nestling hunger the present knowledge about the specific behavioural features that convey the information is still scarce. The aim of this study was to describe begging calls of Iberian Azure-winged Magpie Cyanopica (cyana) cooki nestlings and examine how information on nestling hunger might be encoded in the begging calls. Nestlings were experimentally submitted to different periods of food deprivation and the call variation within individuals was studied. The young were individually tested and stimulated to beg by simulating parental visits. When subject to increasing food deprivation periods, nestlings increased the response level to simulated parental visits. The study also found that for the studied size differences, nestlings did not differ in their response level. Results confirmed that information on nestlings' hunger might be encoded in parameters of the calling behaviour. When the food deprivation periods increased, nestlings tended to start begging earlier, begged more often, extended their calling bout and increased the call duration, changing both at the level of the call and vocal begging bout. Overall the results support the view of begging as an honest signal, namely that begging should reflect nestling hunger and that only some call features might encode information about hunger. 相似文献
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MILTON L. WAINBERG KAREN MCKINNON KATHERINE ELKINGTON PAULO E. MATTOS CLAUDIO GRUBER MANN DIANA DE SOUZA PINTO LAURA OTTO-SALAJ FRANCINE COURNOS AND THE INVESTIGATORS OF PRISSMA 《World psychiatry》2008,7(3):166-172
We conducted the first study to examine rates of sexual activity, sexual risk behaviors, sexual protective behaviors, injection drug use (IDU), needle sharing, and knowledge about HIV/AIDS among outpatients with severe mental illness (SMI) in Rio de Janeiro, Brazil. Using a measure with demonstrated reliability, we found that 42% of 98 patients engaged in vaginal or anal sex within the past three months. Comorbid substance use disorder was significantly associated with sexual activity. Only 22% of sexually active patients used condoms consistently, despite having better HIV knowledge than those who were sexually abstinent. Overall, 45% of patients reported not engaging in any HIV protective behaviors. There were no reports of drug injection. Adults with SMI in Brazil are in need of efficacious HIV prevention programs and policies that can sustain these programs within mental health treatment settings. 相似文献
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