25 documentos corresponden a la consulta.
Palabras contadas: fly: 32
Lombardi, C.M. - Charbuki, M.
Iheringia Ser. Zool. 2002;92(1):105-109
2002
Descripción: A change in bird density within a captive flock of Sicalis flaveola pelzeni (Sclater, 1872) affected the decision to join a group. Ruling out inter-individual differences and maintaining constant the size of a food patch, birds were found to fly more often to the food source and spend a longer time in its environs when kept in greater groups.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Cendra, P.G. - Segura, D. - Allinghi, A. - Cladera, J. - Vilardi, J.
Fla. Entomol. 2007;90(1):147-153
2007
Temas: Anastrepha fraterculus - Genetic control - Longevity - SIT - Survival - comparative study - fly - integrated approach - longevity - sterile release method
Descripción: The South American fruit fly Anastrepha fraterculus (Wiedemann) is one of the most destructive fruit pests in this region, infesting major fruit crops. Implementation of the sterile insect technique (SIT) as part of an area-wide integrated approach against this species requires information on the survival of mass-reared and sterilized insects in the field and their ability to mate with wild females. The survival rates in field cages of both non-irradiated and irradiated laboratory flies were compared with that of wild flies. Both types of laboratory flies survived longer than their wild counterparts over the 8 days under the experimental conditions. The irradiation dose (70 Gy) did not affect survival of the laboratory reared flies. Our results improve the prospect of integrating the SIT into the control of A. fraterculus populations in Argentina.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Tettamanzi, M.C. - Biurrun, F.N. - Cirigliano, A.M.
Z. Naturforsch. Sect. B J. Chem. Sci. 2007;62(4):573-576
2007
Descripción: A new trechonolide-type withanolide, jaborosolactol, possessing a hemiketal ring system and a 5-membered lactol, has been isolated from the aerial parts of Jaborosa lanigera. The structure was elucidated based on spectroscopic and spectrometric methods (ID and 2D NMR, MS). The feeding deterrent activity of the compound against the Mediterranean fruit fly Ceratitis capitata was examined. © 2007 Verlag der Zeitschrift für Naturforschung.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Allinghi, A. - Gramajo, C. - Willink, E. - Vilardi, J.
Fla. Entomol. 2007;90(1):96-102
2007
Temas: Fertility - Pupal age - SIT - South American fruit fly - Sperm transfer - Sterility - adult - age - dose-response relationship - fertility
Descripción: In relation to the application of the sterile insect technique (SIT) for the South American fruit fly Anastrepha fraterculus (Wiedemann), we analyzed the effect on adult fertility of different doses of gamma irradiation and the age of pupae at the time of irradiation. In a first experiment, we applied doses of 50, 70, and 90 Gy to pupae at 24, 48, 72, and 96 h before adult emergence. In a second experiment we irradiated pupae 48 h before emergence with 20, 40, and 60 Gy and estimated male and female fertility and sperm transfer by irradiated males. The results indicated pupal age at irradiation does not significantly affect male fertility. If males irradiated with 60 Gy are crossed to non-irradiated females the fertility is about 1%. Females irradiated with 40 Gy did not lay eggs independently of the male to which they mated. No significant effects of radiation were observed with respect to the ability of males to transfer sperm. A dose of 70 Gy applied 48 h before adult emergence induces 100% sterility in both males and females.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Segura, D.F. - Utgés, M.E. - Liendo, M.C. - Rodríguez, M.F. - Devescovi, F. - Vera, M.T. - Teal, P.E.A. - Cladera, J.L.
J. Appl. Entomol. 2013;137(SUPPL1):19-29
2013
Temas: Juvenile hormone - Sexual maturation - South American fruit fly - Sterile insect technique - copulation - fruit - hormone - juvenile - maturation - pest control
Descripción: Fil:Segura, D.F. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Braberman, V. - Olivero, A. - Schapachnik, F.
Electron. Notes Theor. Comput. Sci. 2005;128(3):3-18
2005
Temas: Distributed Timed Model Checking - Kronos - Load-Balance - Prediction - Reachability - Reconfiguration - Redistribution - Timed Automata - Zeus - Algorithms
Descripción: In this work we present the on-the-fly workload prediction and redistribution techniques used in Zeus [12, 13], a Distributed Model Checker that evolves from the tool Kronos [14]. After reviewing why it is so hard to have good speedups in distributed timed model checking, we present the methods used to get promising results when verifying reachability properties over timed automata [3]. © 2005 Elsevier B.V.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Deans, A.M. - Smith, S.M. - Malcolm, J.R. - Crins, W.J. - Bellocq, M.I.
Environ. Entomol. 2007;36(2):308-318
2007
Temas: Boreal forest - Functional assemblages - Species richness - Syrphidae - Variable retention harvesting - abundance - boreal forest - community composition - community response - coniferous forest
Descripción: Variable retention harvesting (VRH), in which trees are removed at variable intensity and spatial configuration across the landscape, retains greater forest structural heterogeneity than traditional clear-cut harvesting and is being recommended as an alternative for sustainable management of the boreal forest. Little is known about its effects on forest fauna; thus, we studied the influence of one type of VRH (harvesting with advanced regeneration [HARP]) on the Syrphidae (Diptera) community in northern Ontario forests of peatland black spruce (Picea mariana). We examined the effects of varying structural retention (from unharvested through partial retention to clear-cut) on syrphid species richness and abundance, and abundance of functional assemblages. Greater species richness and population abundances were found generally in harvested than in unharvested forests. Overall species richness and the abundance of four species (Platycheirus rosarum, Toxomerus marginatum, Xylota annulifera, and X. tuberculata) and larval predators were all higher in both clear-cut sites and those with structural retention than in unharvested sites. Similarly, overall species richness and the abundance of nine species were higher in clear-cut than in unharvested sites. Species responses are discussed in an ecological context. Differences among the levels of forest retention harvesting were relatively minor compared with those of the clear-cut and unharvested area, suggesting that local habitat characteristics may play a more important role in determining the syrphid community than the landscape configuration. However, a landscape level effect was evident, suggesting that syrphids may be useful in reflecting changes in stand structure at the landscape scale. © 2007 Entomological Society of America.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Allinghi, A. - Calcagno, G. - Petit-Marty, N. - Cendra, P.G. - Segura, D. - Vera, T. - Cladera, J. - Gramajo, C. - Willink, E. - Vilardi, J.C.
Fla. Entomol. 2007;90(1):27-32
2007
Temas: Anastrepha fraterculus - Fruit fly - Irradiation - Mating compatibility - Mating indices - Tephritidae - fly - intraspecific competition - irradiation - laboratory method
Descripción: We evaluated under semi-natural field cage conditions sexual compatibility and competitiveness of a laboratory strain (LAB) compared to a wild population (TUC) of Anastrepha fraterculus (Wiedemann). The LAB strain is produced under semi-mass rearing conditions at the Estación Experimental Agroindustrial Obispo Colombres facility (Tucumán, Argentina). Wild flies were obtained at Horco Molle (Tucumán, Argentina) from infested guava fruits. LAB pupae were irradiated (60Co) 48 h before adult emergence. The tested doses were 0 (control), 40, 70, and 100 Gy. Twenty-five males and 25 females each of TUC and LAB were released into cages and mating pairs collected. Only 1 irradiation dose was considered at a time. Females were separated and allowed to lay eggs into artificial fruits to estimate induced sterility from the corresponding hatching rate. Copulation start time did not differ significantly between strains nor among irradiation treatments. Copulation duration showed highly significant differences among irradiation doses, but no differences between strains. The index of sexual isolation (ISI) and the relative sterility index (RSI) indices indicated that LAB and TUC are fully compatible, males from TUC and LAB did not differ in mating competitiveness, and irradiation within the range tested did not affect these indices. Non-irradiated LAB females exhibited higher mating propensity than TUC ones. However, a significant reduction in the female relative performance index (FRPI) index was observed with increasing irradiation dose. The analysis of induced sterility indicated that treatment with 40 Gy reduces male fertility from about 80% to 0.75%, and higher doses produce total sterility. In females, the 40 Gy dose reduces fertility to about 2% and higher doses prevent egg laying.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Chirino, M.G. - Folgarait, P.J. - Gilbert, L.E. - Lanzavecchia, S. - Papeschi, A.G.
Genet. Mol. Biol. 2009;32(4):740-747
2009
Temas: C-banding - FISH - Fluorescent banding - Karyotype evolution - Pseudacteon - DNA 18S - animal cell - animal experiment - ant - article
Descripción: Pseudacteon flies, parasitoids of worker ants, are being intensively studied as potentially effective agents in the biological control of the invasive pest fire ant genus Solenopsis (Hymenoptera: Formicidae). This is the first attempt to describe the karyotype of P. curvatus Borgmeier, P. nocens Borgmeier and P. tricuspis Borgmeier. The three species possess 2n = 6; chromosomes I and II were metacentric in the three species, but chromosome pair III was subtelocentric in P. curvatus and P. tricuspis, and telocentric in P. nocens. All three species possess a C positive band in chromosome II, lack C positive heterochromatin on chromosome I, and are mostly differentiated with respect to chromosome III. P. curvatus and P. tricuspis possess a C positive band, but at different locations, whereas this band is absent in P. nocens. Heterochromatic bands are neither AT nor GC rich as revealed by fluorescent banding. In situ hybridization with an 18S rDNA probe revealed a signal on chromosome II in a similar location to the C positive band in the three species. The apparent lack of morphologically distinct sex chromosomes is consistent with proposals of environmental sex determination in the genus. Small differences detected in chromosome length and morphology suggests that chromosomes have been highly conserved during the evolutionary radiation of Pseudacteon. Possible mechanisms of karyotype evolution in the three species are suggested. Copyright © 2009, Sociedade Brasileira de Genética.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Segura, D. - Petit-Marty, N. - Sciurano, R. - Vera, T. - Calcagno, G. - Allinghi, A. - Cendra, P.G. - Cladera, J. - Vilardi, J.
Fla. Entomol. 2007;90(1):154-162
2007
Temas: Anastrepha fraterculus - Field cages - Lek - Mating behavior - Morphometric traits - Sexual selection - South American fruit fly - fly - lek - male behavior
Descripción: Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) displays a lek mating system. Males form groups in which they simultaneously display signals (acoustical, visual, or chemical) to attract females with the purpose of mating. Females visit the lek and choose among signaling and courting males to mate. Scarce information is available in A. fraterculus about the main factors involved in female choice and the behavior of displaying males. This information could be important within the context of pest control programs with a sterile insect technique (SIT) component, because departures from normal sexual behavior caused by artificial rearing could affect males' performance in the field. In this study we assessed A. fraterculus male behavior within the leks and analyzed the importance of behavioral and morphological traits on their copulatory success. The existence of preferred places for lek formation was evaluated in field cages with trees inside and analyzed by dividing the trees in sectors according to a 3-dimensional system. Males were individually weighed, marked, and observed every 15 min. Morphometric and behavioral characteristics of successful and unsuccessful males were compared. Most successful males grouped in a region of the tree characterized by the highest light intensity in the first 2 h of the morning. Results showed that pheromone calling activity is positively associated with copulatory success. Copulations were more frequent for males calling inside the lek, indicating that pheromone calling activity and presence in the lek are key factors for copulatory success. A positive association between copulatory success and eye length was found; some characteristics of the face were also associated with copula duration and latency.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Scannapieco, A.C. - Sambucetti, P. - Norry, F.M.
Biol. J. Linn. Soc. 2009;97(4):738-748
2009
Temas: Chill-coma recovery - Cline - Early fecundity - Heat knockdown resistance - Longevity selection - Senescence - Starvation - Trade-off - biological development - cline
Descripción: The possible associations between longevity, early fecundity, and stress-resistance traits were explored using artificial selection on longevity in a laboratory population of Drosophila buzzatii. Three replicated lines were selected for increased lifespan (L lines) and compared with the respective unselected controls (C lines) after the 14th generation of selection. Mean longevity exhibited a significant response to selection. The baseline mortality tended to decrease in the L lines and a negative correlated response to longevity selection was found for early fecundity. Egg-to-adult developmental time increased in L lines. Longevity selection increased stress resistance for both high and low temperatures, as measured by heat knockdown resistance and chill-coma recovery. Starvation resistance also tended to be higher in L than in C lines. The results obtained are consistent with the hypothesis of trade-offs between longevity and early fecundity, and also suggest a trade-off association between adult longevity and developmental time. Correlated selection responses were generally consistent with correlations among the traits previously inferred from altitudinal clines for longevity and stress-resistance phenotypes. © 2009 The Linnean Society of London.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Soto, I.M. - Hasson, E.R. - Manfrin, M.H.
Biol. J. Linn. Soc. 2008;95(4):655-665
2008
Temas: Cactus - Geometric morphometrics - Morphological evolution - Phenotypic plasticity - divergence - evolution - fly - host plant - morphometry - Neotropical region
Descripción: A central issue in evolutionary biology is to understand the mechanisms promoting morphological evolution during speciation. In a previous study, we showed that the Neotropical cactophilic sibling species Drosophila gouveai and Drosophila antonietae can be reared in media prepared with their presumptive natural host plants (Pilosocereus machrisis and Cereus hildmaniannus) and that egg to adult viability is not independent of the cactus host. In the present study, we investigate the effects of ecological and genetic factors on interspecific divergence in wing morphology, in relation to the pattern of wing venation and phenotypic plasticity in D. gouveai and D. antonietae, by means of the comparative analysis of isofemale lines reared in the two cactus hosts. The species differed significantly in wing size and shape, although specific differences were mainly localized in a particular portion of the wing. We detected significant variation in form among lines, which was not independent of the breeding cactus, suggesting the presence of genetic variation for phenotypic plasticity and wing shape variation in both species. We discuss the results considering the plausible role of host plant use in the evolutionary history of cactophilic Drosophila inhabiting the arid zones of South America. © 2008 The Linnean Society of London.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Fernández Iriarte, P.J. - Balanyà, J. - Pascual, M. - Mestres, F. - Hasson, E.R. - Fontdevila, A. - Serra, L.
J. Evol. Biol. 2009;22(3):650-658
2009
Temas: Bottleneck - Colonization - Inversion polymorphism - Lethal genes - Microsatellite loci - microsatellite DNA - allele - biological invasion - colonization - fly
Descripción: Biological invasions are excellent opportunities to study the evolutionary forces leading to the adaptation of a species to a new habitat. Knowledge of the introduction history of colonizing species helps tracking colonizing routes and assists in defining management strategies for invasive species. The Palearctic species Drosophila subobscura is a good model organism for tracking colonizations since it was detected in Chile and western North America three decades ago and later on in the Atlantic coast of Argentina. To unravel the origin of the Argentinean colonizers two populations have been analysed with several genetic markers. Chromosomal arrangements and microsatellite alleles found in Argentina are almost similar to those observed in Chile and USA. The lethal allelism test demonstrates that the lethal gene associated with the O5 inversions in Argentina is identical to that found in Chile and USA, strongly supporting the hypothesis that all the American colonizing populations originated from the same colonization event. A secondary bottleneck is detected in the Argentinean populations and the genetic markers suggest that these populations originated from the invasion of 80-150 founding individuals from Chile. © 2008 European Society For Evolutionary Biology.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Fernández Iriarte, P.J. - Levy, E. - Devincenzi, D. - Rodríguez, C. - Fanara, J.J. - Hasson, E.
Hereditas 1999;131(2):93-99
1999
Temas: animal tissue - article - chromosome inversion - Drosophila - environment - genetic drift - genetic heterogeneity - genetic polymorphism - genetic variability - nonhuman
Descripción: The inversion polymorphism of the cactophilic fly Drosophila buzzatii was studied in two natural populations. We assessed the temporal changes and microspatial population structure. We observed a significant increase in the frequency of arrangement 2J at the expense of 2ST in both populations. These gene arrangements appear to affect the life-history of flies differently. Environmental heterogeneity explains the karyotype coexistence in nature. The analysis of population structure showed that differentiation of inversion frequencies among individual breeding sites, the rotting clacodes of Opuntia vulgaris, was highly significant. The karyotypic frequencies did not depart significantly from Hardy-Weinberg expectations, neither in individual rots nor in the total population. These results suggest that the observed population structure can be easily accounted by random genetic drift.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Briceño, D. - Eberhard, W. - Vilardi, J. - Cayol, J.-P. - Shelly, T.
Fla. Entomol. 2007;90(1):15-18
2007
Temas: Argentina - Costa Rica - Courtship behavior - Geographic differences - Hawaii - Madeira - Medfly - Wild flies - courtship - fly
Descripción: This study documents differences in the courtship behavior of wild strains of Ceratitis capitata (Wiedemann) from Madeira (Portugal), Hawaii (U.S.A.), Costa Rica, and Patagonia (Argentina). Some traits showed large variations and others substantial overlaps. The angle at which the male faced toward the female at the moment of transition from continuous wing vibration and intermittent buzzing changed very little during the course of courtship in all strains, but males from Madeira tended to face more directly toward the female than other males. Females tended to look more, and more directly, toward the males as courtship progressed in all strains. The distance between male and female tended to decrease as courtship proceeded in all strains, but the distances at which males initiated continuous vibration, intermittent buzzing, and jumped onto the female were relatively less variable between strains, except for the strain from Costa Rica. Flies of Madeira courted for longer and the male moved his head and buzzed his wings longer than the other strains.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Sciurano, R. - Segura, D. - Rodriguero, M. - Cendra, P.G. - Allinghi, A. - Cladera, J.L. - Vilardi, J.
Fla. Entomol. 2007;90(1):163-170
2007
Temas: Anastrepha fraterculus - Morphology - Morphometric analysis - Multivariate statistical techniques - Sexual selection - Sterile insect technique - competition (ecology) - fly - male behavior - mating behavior
Descripción: Despite the interest in applying environmentally friendly control methods such as sterile insect technique (SIT) against Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), information about its biology, taxonomy, and behavior is still insufficient. To increase this information, the present study aims to evaluate the performance of wild flies under field cage conditions through the study of sexual competitiveness among males (sexual selection). A wild population from Horco Molle, Tucumán, Argentina was sampled. Mature virgin males and females were released into outdoor field cages to compete for mating. Morphometric analyses were applied to determine the relationship between the multivariate phenotype and copulatory success. Successful and unsuccessful males were measured for 8 traits: head width (HW), face width (FW), eye length (EL), thorax length (THL), wing length (WL), wing width (WW), femur length (FL), and tibia length (TIL). Combinations of different multivariate statistical methods and graphical analyses were used to evaluate sexual selection on male phenotype. The results indicated that wing width and thorax length would be the most probable targets of sexual selection. They describe a nonlinear association between expected fitness and each of these 2 traits. This nonlinear relation suggests that observed selection could maintain the diversity related to body size.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Lavagnino, N.J. - Anholt, R.R.H. - Fanara, J.J.
J. Evol. Biol. 2008;21(4):988-996
2008
Temas: Behaviour - Chemical ecology - Genetic variation - Phenotypic plasticity - Quantitative genetics - chemical ecology - fly - genetic variation - genotype-environment interaction - olfaction
Descripción: Odour-guided behaviour is a quantitative trait determined by many genes that are sensitive to gene-environment interactions. Different natural populations are likely to experience different selection pressures on the genetic underpinnings of chemosensory behaviour. However, few studies have reported comparisons of the quantitative genetic basis of olfactory behaviour in geographically distinct populations. We generated isofemale lines of Drosophila melanogaster from six populations in Argentina and measured larval and adult responses to benzaldehyde. There was significant variation within populations for both larval and adult olfactory behaviour and a significant genotype × sex interaction (GSI) for adult olfactory behaviour. However, there is substantial variation in the contribution of GSI to the total phenotypic variance among populations. Estimates of evolvability are orders of magnitude higher for larvae than for adults. Our results suggest that the potential for evolutionary adaptation to the chemosensory environment is greater at the larval feeding stage than at the adult reproductive stage. © 2008 The Authors.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Corio, C. - Soto, I.M. - Carreira, V. - Padró, J. - Betti, M.I.L. - Hasson, E.
Biol. J. Linn. Soc. 2013;109(2):342-353
2013
Temas: Alkaloids - Cactus - Host shifts - Viability - Wing morphology - adult - alkaloid - cactus - concentration (composition) - evolutionary biology
Descripción: The host-plant environment of phytophagous insects directly affects various aspects of an insect's life cycle. Interestingly, relatively few insect groups have specialized in the exploitation of plants in the Cactaceae family, potentially because of the chemical and ecological challenges imposed by these plants. The cactophilic Drosophila buzzatiiPatterson & Wheeler, 1942 is a well-studied model in evolutionary ecology, partially because of its ability to exploit toxic cactus hosts. Previous studies have shown a negative effect on performance when flies are reared in an alternative columnar cactus host of the genus Trichocereus, relative to its primary cactus host, Opuntia. These observations were attributed to the presence of alkaloids in Trichocereus tissues, a chemical deterrent to herbivores that indirectly affects Drosophila larvae; however, the putative toxic effect of alkaloids has never been tested directly in D. buzzatii. The present study is the first attempt to relate chemical extracts in Trichocereus terscheckii Britton & Rose, 1920 with detrimental effects on D. buzzatii. We assessed the effects of a crude alkaloid extract, rich in phenylethylamines, and a 'non-alkaloid fraction' on viability and adult wing morphology. Our results indicate that rearing larvae on an artificial diet containing different concentrations of the crude alkaloid extract decreased pupal viability and adult size in a concentration-dependent manner. We discuss the role of cactus alkaloids in the evolution of host-plant use in cactophilic flies. © 2013 The Linnean Society of London.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Lanzavecchia, S. - Remis, M. - Cladera, J. - Zandomeni, R.
Entomol. Exp. Appl. 2010;136(1):53-65
2010
Temas: Diptera - EPIC-PCR - Exon priming intron crossing-polymerase chain reaction - Gene flow - Medfly - Migration patterns - Molecular markers - Population genetics - Tephritidae - allele
Descripción: DNA size polymorphisms were utilized in a study of 24 natural populations of Ceratitis capitata Wiedemann (Diptera: Tephritidae) from Argentina. The first intron of alcohol dehydrogenase 1 gene (Adh1) was amplified using exon priming intron crossing-polymerase chain reaction. Three size variants were detected among the 307 samples analyzed. To better differentiate the size variants, further digestion of PCR products with the EcoRI restriction enzyme was carried out. Complete nucleotide sequences of the three-allele variants were obtained and single changes, insertions, deletions, and EcoRI recognition sites were located. Population allele frequencies were analyzed and a global mean heterozygosity (He) of 0.33 was obtained. In most populations, observed allelic frequencies conformed to Hardy-Weinberg expectations. Significant differences between provinces and sampling sites within these provinces, and among some populations were found. The average number of insects exchanged among populations (Nm) was estimated and high values were observed between Argentina and populations from two African countries (Morocco and Kenya), Australia, and Hawaii (Kauai). Pest introduction sources and dispersion patterns in Argentina are discussed based on these results as well as on available bibliographical data. © 2010 The Authors. Journal compilation © 2010 The Netherlands Entomological Society.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
Folguera, G. - Ceballos, S. - Spezzi, L. - Fanara, J.J. - Hasson, E.
Biol. J. Linn. Soc. 2008;95(2):233-245
2008
Temas: Thermal adaptation - Thermal amplitude-clines - adaptation - behavioral response - biological development - brood rearing - cline - fly - invasive species - temperature effect
Descripción: The present study first addressed the question of whether developmental time (DT) and viability (VT) vary clinally along latitudinal and altitudinal gradients in Drosophila buzzatii, an autochthonous specialist and the generalist invasive Drosophila melanogaster. Coincident and positive altitudinal clines across species and, direct and inverse latitudinal clines were observed for DT in D. melanogaster and D. buzzatii, respectively. Opposing latitudinal and altitudinal clines were detected for VT only in D. melanogaster. The patterns observed along altitudinal gradients prompted us to investigate whether flies living at lowland and highland environments may respond differentially to thermal treatments consisting of regimes of constant and alternating temperatures. Flies reared at higher mean temperature developed faster than at lower mean temperature in both species. By contrast, the response in VT differed greatly between species. Highland D. melanogaster were more viable than lowland regardless the treatment, whereas, in D. buzzatii, highland flies were more viable than lowland in alternating thermal regimes and the reverse was true in treatments of constant temperature. The results obtained suggest that thermal amplitude may be an important factor that should be considered in investigations of thermal adaptation. © 2008 The Linnean Society of London.
...ver más Tipo de documento: info:ar-repo/semantics/artículo
< Anteriores
(Resultados 21 - 25)