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111.
JOSÉ ARTURO ALCÁNTARA‐RODRÍGUEZ JORGE CIROS‐PÉREZ ELIZABETH ORTEGA‐MAYAGOITIA CARMEN R. SERRANIA‐SOTO ELÍAS PIEDRA‐IBARRA 《Freshwater Biology》2012,57(4):728-740
1. Salinity is a strong selective force for many aquatic organisms, affecting both ecological and evolutionary processes. Most of our knowledge on the effects of salinity on rotifers in the Brachionus plicatilis species complex is based mainly on populations from waterbodies that experience broad environmental changes both seasonally and annually. We tested the hypothesis that, despite the supposedly high potential for gene flow among rotifers inhabiting neighbouring environments, constant salinity has promoted local adaptation, genetic population divergence and even cryptic speciation in B. plicatilis complex populations from three deep maar lakes of distinct salinities [1.1, 6.5 and 9.0 g L?1 total dissolved solids (TDS)] in Central Mexico. 2. To look for local adaptation, we performed common garden experiments to test the effect of different salinities on population density and intrinsic growth rate (r). Then, we evaluated the genetic divergence by sequencing the cytochrome c oxidase subunit I (COI) gene and performed reproductive trials to assess the potential gene flow among the three populations and with other closely related B. plicatilis complex species. 3. We confirmed that the rotifer populations have phenotypic plasticity in tolerance of salinity, but only rotifers from the least saline lake are adapted to low salinity. Among the populations, sequence divergence at COI was very low (just a single haplotype was found), suggesting a persistent founder effect from a relatively recent single colonisation event and a subsequent dispersal from one lake to the others, and a very restricted immigration rate. In the phylogenetic analysis, rotifers from this area of Mexico clustered in the same clade with the middle‐sized species Brachionus ibericus and B. sp. ‘Almenara’. Mexican rotifers showed successful recognition, copulation and formation of hybrids among them, but interpopulation breeding with the Spanish B. ibericus and B. sp. ‘Almenara’ was unsuccessful. 4. We conclude that the B. plicatilis complex populations from these three lakes belong to a new biological species not yet described (presently named B. sp. ‘Mexico’). To our knowledge, this is the first report of local adaptation of a natural B. plicatilis complex population living in freshwater conditions (1.1 g L?1 TDS). 相似文献
112.
A. L. T. MELO R. WITTER T. F. MARTINS T. A. PACHECO A. S. ALVES C. S. CHITARRA V. DUTRA L. NAKAZATO R. C. PACHECO M. B. LABRUNA D. M. AGUIAR 《Medical and veterinary entomology》2016,30(1):112-116
Tick and blood samples collected from domestic dogs in the Brazilian Pantanal were tested by molecular methods for the presence of tick‐borne protozoa and bacteria. Among 320 sampled dogs, 3.13% were infected by Babesia vogeli (Piroplasmida: Babesiidae), 8.75% by Hepatozoon canis (Eucoccidiorida: Hepatozoidae), 7.19% by Anaplasma platys (Rickettsiales: Anaplasmataceae), and 0.94% by an unclassified Anaplasma sp. In three tick species collected from dogs, the following tick‐borne agents were detected: (a) B. vogeli, An. platys and Ehrlichia canis (Rickettsiales: Anaplasmataceae), infecting Rhipicephalus sanguineus sensu lato (Ixodida: Ixodidae) ticks; (b) H. canis, an unclassified Anaplasma sp. and Rickettsia amblyommii (Rickettsiales: Rickettsiaceae), infecting Amblyomma cajennense sensu lato (Ixodida: Ixodidae) ticks, and (c) Rickettsia sp. strain Atlantic rainforest, an emerging human pathogen, infecting Amblyomma ovale ticks. Molecular analysis, based on a mitochondrial gene, revealed that the Am. cajennense s.l. ticks of the present study corresponded to Amblyomma sculptum, a member of the Am. cajennense species complex, and that Rh. sanguineus s.l. belonged to the tropical lineage. Whereas dogs are exposed to a number of tick‐borne bacterial and protozoan agents in the Pantanal biome, humans are potentially exposed to infection by spotted fever group rickettsiae (e.g. R. amblyommii and Rickettsia sp. strain Atlantic rainforest) because both Am. sculptum and Am. ovale are among the most important human‐biting ticks in Brazil. 相似文献
113.
Abstract: Eight fossil (Cretaceous) insect cocoons were discovered within the infillings of a broken dinosaur egg of a clutch from a Patagonian locality. Cocoons are considered to be in situ based on detailed preservation of thin, delicate walls with surface texture, infillings that are similar to the surrounding rock matrix and the clustered distribution of cocoons in only one egg out of the clutch of five eggs. According to the shape, size, and thin wall with surface texture, the cocoons are interpreted as having been produced by wasps. The wasps may have been attracted to the egg because of the presence of scavenging insects feeding on the decaying organic matter, or they may have been attracted to spiders feeding on the scavenging insects. In either scenario, after attacking the insects or spiders inside the sand infillings of the egg, the wasp larvae produced the cocoons described herein. The presence of wasps, which are at the top of the scavenging food webs, suggests that a complex community of invertebrates would have developed around rotten dinosaur eggs. 相似文献
114.
EDUARDO G. MARTINS SCOTT G. HINCH DAVID A. PATTERSON MERRAN J. HAGUE STEVEN J. COOKE KRISTINA M. MILLER MICHAEL F. LAPOINTE KARL K. ENGLISH ANTHONY P. FARRELL 《Global Change Biology》2011,17(1):99-114
Mean summer water temperatures in the Fraser River (British Columbia, Canada) have increased by ~1.5 °C since the 1950s. In recent years, record high river temperatures during spawning migrations of Fraser River sockeye salmon (Oncorhynchus nerka) have been associated with high mortality events, raising concerns about long‐term viability of the numerous natal stocks faced with climate warming. In this study, the effect of freshwater thermal experience on spawning migration survival was estimated by fitting capture–recapture models to telemetry data collected for 1474 adults (captured in either the ocean or river between 2002 and 2007) from four Fraser River sockeye salmon stock‐aggregates (Chilko, Quesnel, Stellako‐Late Stuart and Adams). Survival of Adams sockeye salmon was the most impacted by warm temperatures encountered in the lower river, followed by that of Stellako‐Late Stuart and Quesnel. In contrast, survival of Chilko fish was insensitive to the encountered river temperature. In all stocks, in‐river survival of ocean‐captured sockeye salmon was higher than that of river‐captured fish and, generally, the difference was more pronounced under warm temperatures. The survival–temperature relationships for ocean‐captured fish were used to predict historic (1961–1990) and future (2010–2099) survival under simulated lower river thermal experiences for the Quesnel, Stellako‐Late Stuart and Adams stocks. A decrease of 9–16% in survival of all these stocks was predicted by the end of the century if the Fraser River continues to warm as expected. However, the decrease in future survival of Adams sockeye salmon would occur only if fish continue to enter the river abnormally early, towards warmer periods of the summer, as they have done since 1995. The survival estimates and predictions presented here are likely optimistic and emphasize the need to consider stock‐specific responses to temperature and climate warming into fisheries management and conservation strategies. 相似文献
115.
IGNACIO M. PÉREZ-RAMOS TEODORO MARAÑÓN JORGE M. LOBO JOSÉ R. VERDÚ 《Ecological Entomology》2007,32(4):349-356
Abstract. 1. Plant–animal interactions, and in particular the processes of seed predation and dispersal, are crucial for tree regeneration and forest dynamics. A novel and striking case of interaction between a dung beetle ( Thorectes lusitanicus ) and two Quercus species ( Q. suber and Q. canariensis ) in forests of southern Spain is presented here.
2. During the autumn, T. lusitanicus beetles (endemic to the southern Iberian Peninsula) bury and feed on single-seeded fruits (acorns) of Quercus , with important ecological implications.
3. Field experiments found differences in the removal rate of acorns by T. lusitanicus , depending on the type of microsite within the forest, the species of oak, the exclosure of large herbivores, and the forest site.
4. Acorn consumption by T. lusitanicus was studied under laboratory conditions, confirming for the first time that this dung beetle is a legitimate seed predator.
5. In addition, some buried acorns can be abandoned partially predated or even intact, and emerge as seedlings; thus, T. lusitanicus also has a potential role as secondary seed disperser. 相似文献
2. During the autumn, T. lusitanicus beetles (endemic to the southern Iberian Peninsula) bury and feed on single-seeded fruits (acorns) of Quercus , with important ecological implications.
3. Field experiments found differences in the removal rate of acorns by T. lusitanicus , depending on the type of microsite within the forest, the species of oak, the exclosure of large herbivores, and the forest site.
4. Acorn consumption by T. lusitanicus was studied under laboratory conditions, confirming for the first time that this dung beetle is a legitimate seed predator.
5. In addition, some buried acorns can be abandoned partially predated or even intact, and emerge as seedlings; thus, T. lusitanicus also has a potential role as secondary seed disperser. 相似文献
116.
JERONI GALMÉS JOAN MANUEL OCHOGAVÍA JORGE GAGO EMILIO JOSÉ ROLDÁN JOSEP CIFRE MIQUEL ÀNGEL CONESA 《Plant, cell & environment》2013,36(5):920-935
In a previous study, important acclimation to water stress was observed in the Ramellet tomato cultivar (TR) from the Balearic Islands, related to an increase in the water‐use efficiency through modifications in both stomatal (gs) and mesophyll conductances (gm). In the present work, the comparison of physiological and morphological traits between TR accessions grown with and without water stress confirmed that variability in the photosynthetic capacity was mostly explained by differences in the diffusion of CO2 through stomata and leaf mesophyll. Maximization of gm under both treatments was mainly achieved through adjustments in the mesophyll thickness and porosity and the surface area of chloroplasts exposed to intercellular airspace (Sc). In addition, the lower gm/Sc ratio for a given porosity in drought‐acclimated plants suggests that the decrease in gm was due to an increased cell wall thickness. Stomatal conductance was also affected by drought‐associated changes in the morphological properties of stomata, in an accession and treatment‐dependent manner. The results confirm the presence of advantageous physiological traits in the response to drought stress in Mediterranean accessions of tomato, and relate them to particular changes in the leaf anatomical properties, suggesting specific adaptive processes operating at the leaf anatomical level. 相似文献
117.
NATALIA LILIANA CLEMENTE ALICIA NOEMÍ LÓPEZ MARÍA GLORIA MONTERUBBIANESI NÉSTOR JORGE CAZZANIGA PABLO LUIS MANETTI 《Invertebrate reproduction & development.》2013,57(1-2):23-30
Summary In the southeast of Buenos Aires Province (Argentina), slugs cause reductions in crop yield by killing seeds and seedlings, by destroying stems and growing points, and by reducing leaf area. Deroceras reticulatum (Müller, 1774) was introduced into Argentina a long time ago, but the biology and ecology of this species in this country are still unknown. The aim of this study was to determine how temperature affects growth rate, reproduction and survival of D. reticulatum and also to assess the seasonal phenology of this species. The life cycle of D. reticulatum was investigated at 12°C, 20°C and at a temperature which alternated between 12°C for 16 h and 20°C for 8 h. The light/dark regime during the experiment was LD: 8/16 h. Slug populations were sampled from grassland located at the Experimental Station of INTA Balcarce. Eggs hatched after 16.3 to 39.8 days and fertility varied between 83.9% and 91.1%. The mean time from hatching to oviposition was longer and fecundity lower at 20°C than 12°C and 12/20°C (p <0.05). The net reproductive rate was 1.49 to 70.53 and the mean generation time varied between the 27 and 30 weeks. In natural conditions, eggs of D. reticulatum were found from early winter until the end of the spring, when soil temperature was 8–15°C and humidity was above 15%. These results indicate that D. reticulatum has one generation per year, univoltine phenology, with peak densities of slugs from the beginning of winter to the end of spring, which coincides with the sowing and emergence of winter and summer crops. 相似文献
118.
SÉRGIO P. ÁVILA P. J. MELO ANA LIMA ANDRÉ AMARAL A. M. DE FRIAS MARTINS ARMINDO RODRIGUES 《Invertebrate reproduction & development.》2013,57(1-2):31-40
Summary The reproductive cycle of an Alvania species is studied for first time. Alvania mediolittoralis Gofas, 1989 is an endemic Azorean rissoid very common in sheltered places and particularly abundant among the algal turf covering the lower half of the intertidal and upper subtidal rocky shores. This species reproduces throughout the year, with two spawning peaks, one during early spring and the other in late autumn. In an attempt to relate to current paleobiogeographical studies, inferences are made regarding the ecological advantages of species with a continuous type of reproduction, on Azorean shores, during glacial episodes. 相似文献
119.
NORMAN SARTORIUS WOLFGANG GAEBEL HELEN‐ROSE CLEVELAND HEATHER STUART TSUYOSHI AKIYAMA JULIO ARBOLEDA‐FLÓREZ ANJA E. BAUMANN OYE GUREJE MIGUEL R. JORGE MARIANNE KASTRUP YURIKO SUZUKI ALLAN TASMAN 《World psychiatry》2010,9(3):131-144
In 2009 the WPA President established a Task Force that was to examine
available evidence about the stigmatization of psychiatry and psychiatrists
and to make recommendations about action that national psychiatric societies
and psychiatrists as professionals could do to reduce or prevent the stigmatization
of their discipline as well as to prevent its nefarious consequences. This
paper presents a summary of the Task Force’s findings and recommendations.
The Task Force reviewed the literature concerning the image of psychiatry
and psychiatrists in the media and the opinions about psychiatry and psychiatrists
of the general public, of students of medicine, of health professionals other
than psychiatrists and of persons with mental illness and their families.
It also reviewed the evidence about the interventions that have been undertaken
to combat stigma and consequent discrimination and made a series of recommendations
to the national psychiatric societies and to individual psychiatrists. The
Task Force laid emphasis on the formulation of best practices of psychiatry
and their application in health services and on the revision of curricula
for the training of health personnel. It also recommended that national psychiatric
societies establish links with other professional associations, with organizations
of patients and their relatives and with the media in order to approach the
problems of stigma on a broad front. The Task Force also underlined the role
that psychiatrists can play in the prevention of stigmatization of psychiatry,
stressing the need to develop a respectful relationship with patients, to
strictly observe ethical rules in the practice of psychiatry and to maintain
professional competence. 相似文献
120.