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Darío C. Colautti Leandro Miranda Mariano Gonzalez-Castro Vanina Villanova Carlos A. Strüssmann Miguel Mancini Tomas Maiztegui Gustavo Berasain Ricardo Hattori Fabian Grosman Pablo Sanzano Ismael Lozano Sabina L. Vegh Victor Salinas Omar Del Ponti Pamela del Fresno Priscila Minotti Yoji Yamamoto Claudio R. M. Baigún 《Journal of fish biology》2020,96(1):202-216
In South America, the order Atheriniformes includes the monophyletic genus Odontesthes with 20 species that inhabit freshwater, estuarine and coastal environments. Pejerrey Odontesthes argentinensis is widely distributed in coastal and estuarine areas of the Atlantic Ocean and is known to foray into estuaries of river systems, particularly in conditions of elevated salinity. However, to our knowledge, a landlocked self-sustaining population has never been recorded. In this study, we examined the pejerrey population of Salada de Pedro Luro Lake (south-east of Buenos Aires Province, Argentina) to clarify its taxonomic identity. An integrative taxonomic analysis based on traditional meristic, landmark-based morphometrics and genetic techniques suggests that the Salada de Pedro Luro pejerrey population represents a novel case of physiological and morphological adaptation of a marine pejerrey species to a landlocked environment and emphasises the environmental plasticity of this group of fishes. 相似文献
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Villar Carlos Stripeikis Jorge Colautti Dario D'Huicque Liliana Tudino Mabel Bonetto Carlos 《Hydrobiologia》2001,457(1-3):225-233
Cd, Cr, Cu and Pb concentrations were measured in the water and these plus Zn were measured in the diet, muscle and liver of the detritivorous fish Prochilodus lineatus and the omnivorous fish Pterodoras granulosus at two sites (Lower Paraná River and Río de la Plata right margin) located upstream and downstream, respectively, from Buenos Aires, an important source of xenobiotics. Cu and Cr concentrations in water were higher in the Río de la Plata coastal waters, while Cd and Pb were below detection limits. The stomach contents of P. lineatus showed a higher metal content at the estuary, attaining concentrations within the range reported for contaminated sediments. However, metals in fish tissue were not higher at the estuary and, except for Cd in liver, were lower than in the organic fraction of the stomach content. Thus, only Cd was accumulated. The P. granulosus diet was composed mainly of river vegetation debris and clams, Corbicula fluminea, at the estuary. Cd, Cu and Pb in liver were higher at the estuary while only Cu was higher in the diet at this site. The different nature of the diet seems associated with a differential bioavailability of its metal content. P. granulosus accumulates Cu at both sites and Cd at the estuary. Both fishes showed higher metal content in liver than in muscle. Cr in liver was below detection limits. No relation was found between metal content and fish size. Overall, metal content in fish tissues were low, except for Cu in P. granulosus and Cd in P. lineatus, similar to those of uncontaminated sites, suggesting that homeostatic mechanisms prevent metal accumulation. 相似文献
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Evolution during biological invasion may occur over contemporary timescales, but the rate of evolutionary change may be inhibited by a lack of standing genetic variation for ecologically relevant traits and by fitness trade-offs among them. The extent to which these genetic constraints limit the evolution of local adaptation during biological invasion has rarely been examined. To investigate genetic constraints on life-history traits, we measured standing genetic variance and covariance in 20 populations of the invasive plant purple loosestrife (Lythrum salicaria) sampled along a latitudinal climatic gradient in eastern North America and grown under uniform conditions in a glasshouse. Genetic variances within and among populations were significant for all traits; however, strong intercorrelations among measurements of seedling growth rate, time to reproductive maturity and adult size suggested that fitness trade-offs have constrained population divergence. Evidence to support this hypothesis was obtained from the genetic variance-covariance matrix (G) and the matrix of (co)variance among population means (D), which were 79.8% (95% C.I. 77.7-82.9%) similar. These results suggest that population divergence during invasive spread of L. salicaria in eastern North America has been constrained by strong genetic correlations among life-history traits, despite large amounts of standing genetic variation for individual traits. 相似文献
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We performed an investigation focusing on the distribution of tumor types responsible for positive pleural effusions in 143 patients who died of malignancy and underwent autopsy. The principal malignant tumors were lung carcinoma (41 cases, 51.2%) and pleural mesothelioma (23 cases, 28.7%) in males and breast carcinoma (24 cases, 38.2%) and lung carcinoma (13 cases, 20.6%) in females. Histologically, most of the cases belonged to the adenocarcinoma category. The first morphologic diagnosis was a cytologic one in 86 cases (60.1%), especially regarding lung cancer. In breast cancer a positive pleural effusion always preceded recurrent disease with a rapidly progressive course, even a long time after the initial surgery. The results of this study, based on both cytomorphologic features and postmortem data on the tumor sites, may be a useful working framework for the cytologist dealing with a positive pleural effusion. 相似文献
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Invasions biologists have frequently debated whether the definition of invasive should include ecological and economic impacts. More recent criticisms posit that objective definitions are impossible in
any absolute sense, while subjectivity is desirable for its flexibility and motivational qualities. We argue that such criticisms
underestimate the extent of subjectivity already present in invasion biology. Ecological questions may be methodological if
they relate directly to other ecological theories and models, or motivational if they focus on issues important to society
as a whole. Motivational questions are important for engaging scientists, improving public understanding of science, and often
have applied benefits. In contrast, methodological questions are constrained by established scientific theories, and are therefore
more efficient for the development of scientific knowledge. Contrary to recent critiques, we suggest that greater objectivity
is both achievable and desirable for the discipline of invasion biology and ecology generally. 相似文献
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Elisabetta Friso Gabrio Roncucci Donata Dei Marina Soncin Clara Fabris Giacomo Chiti Paolo Colautti Juan Esposito Laura De Nardo Carlo Riccardo Rossi Donato Nitti Francesca Giuntini Lara Borsetto Giulio Jori 《Photochemical & photobiological sciences》2006,5(1):39-50
The synthesis of a Zn(ii)-phthalocyanine derivative bearing four 10B-enriched o-carboranyl units (10B-ZnB4Pc) and its natural isotopic abundance analogue (ZnB4Pc) in the peripheral positions of the tetraazaisoindole macrocycle is presented. The photophysical properties of ZnB4Pc, as tested against model biological systems, were found to be similar with those typical of other photodynamically active porphyrin-type photosensitisers, including a singlet oxygen quantum yield of 0.67. The carboranyl-carrying phthalocyanine was efficiently accumulated by B16F1 melanotic melanoma cells in vitro, appeared to be partitioned in at least some subcellular organelles and, upon red light irradiation, induced extensive cell mortality. Moreover, ZnB4Pc, once i.v.-injected to C57BL/6 mice bearing a subcutaneously transplanted pigmented melanoma, photosensitised an important tumour response, provided that the irradiation at 600-700 nm was performed 3 h after the phthalocyanine administration, when appreciable concentrations of ZnB4Pc were still present in the serum. Analogously, irradiation of the 10B-ZnB4Pc-loaded pigmented melanoma with thermal neutrons 24 h after injection led to a 4 day delay in tumour growth as compared with control untreated mice. These results open the possibility to use one chemical compound as both a photosensitising and a radiosensitising agent for the treatment of tumours by the combined application of photodynamic therapy and boron neutron capture therapy. 相似文献
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Invasion genetics of the Eurasian spiny waterflea: evidence for bottlenecks and gene flow using microsatellites 总被引:6,自引:0,他引:6
Colautti RI Manca M Viljanen M Ketelaars HA Bürgi H Macisaac HJ Heath DD 《Molecular ecology》2005,14(7):1869-1879
The Eurasian spiny waterflea (Bythotrephes longimanus) is a predacious zooplankter that has increased its range in Europe and is rapidly invading inland water-bodies throughout North America's Great Lakes region. To examine the genetics of these invasions, we isolated five microsatellite DNA loci with between 5 and 19 alleles per locus. We sampled three populations where B. longimanus has been historically present (Switzerland, Italy, and Finland) as well as an introduced European population (the Netherlands) and three North American populations (Lakes Erie, Superior, Shebandowan). Consistent with a bottleneck during colonization (i.e. founder effect), average heterozygosities of the four European populations ranged from 0.310 to 0.599, and were higher than that of three North American populations (0.151-0.220). Pairwise F(ST) estimates among North American populations (0.002-0.063) were not significantly different from zero and were much lower than among European populations (0.208-0.474). This is consistent with a scenario of high gene flow among North American populations relative to that of European ones. Contrary to an invasion bottleneck, however, Erie and Superior populations contained similar numbers of rare alleles as European populations. Assignment tests identified several migrant genotypes in all introduced populations (the Netherlands, Erie, Superior, Shebandowan), but rarely in native ones (Switzerland, Italy and Finland). A large number of genotypes from North America were assigned to our Italian population suggesting a second, previously unidentified, invasion source somewhere in the region of northern Italy. Together, our results support an invasion bottleneck for North American populations that has been largely offset by gene flow from multiple native sources, as well as gene flow among introduced populations. 相似文献
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Is invasion success explained by the enemy release hypothesis? 总被引:10,自引:0,他引:10
Robert I. Colautti Anthony Ricciardi Igor A. Grigorovich Hugh J. MacIsaac 《Ecology letters》2004,7(8):721-733
A recent trend in invasion ecology relates the success of non‐indigenous species (NIS) to reduced control by enemies such as pathogens, parasites and predators (i.e. the enemy release hypothesis, ERH). Despite the demonstrated importance of enemies to host population dynamics, studies of the ERH are split – biogeographical analyses primarily show a reduction in the diversity of enemies in the introduced range compared with the native range, while community studies imply that NIS are no less affected by enemies than native species in the invaded community. A broad review of the invasion literature implies at least eight non‐exclusive explanations for this enigma. In addition, we argue that the ERH has often been accepted uncritically wherever (i) NIS often appear larger, more fecund, or somehow ‘better’ than either congeners in the introduced region, or conspecifics in the native range; and (ii) known enemies are conspicuously absent from the introduced range. However, all NIS, regardless of their abundance or impact, will lose natural enemies at a biogeographical scale. Given the complexity of processes that underlie biological invasions, we argue against a simple relationship between enemy ‘release’ and the vigour, abundance or impact of NIS. 相似文献
10.
Robert I Colautti Sarah A Bailey Colin D. A. van Overdijk Keri Amundsen Hugh J. MacIsaac 《Biological invasions》2006,8(1):45-59
Biological invasions by nonindigenous species (NIS) can have adverse effects on economically important goods and services,
and sometimes result in an ‘invisible tax’ on natural resources (e.g. reduced yield). The combined economic costs of NIS may
be significant, with implications for environmental policy and resource management; yet economic impact assessments are rare
at a national scale. Impacts of nuisance NIS may be direct (e.g. loss of hardwood trees) or indirect (e.g. alteration of ecosystem
services provided by growing hardwoods). Moreover, costs associated with these effects may be accrued to resources and services
with clear ‘market’ values (e.g. crop production) and to those with more ambiguous, ‘non-market’ values (e.g. aesthetic value
of intact forest). We characterised and projected economic costs associated with nuisance NIS in Canada, through a combination
of case-studies and an empirical model derived from 21 identified effects of 16 NIS. Despite a severe dearth of available
data, characterised costs associated with ten NIS in Canadian fisheries, agriculture and forestry totalled $187 million Canadian
(CDN) per year. These costs were dwarfed by the ‘invisible tax’ projected for sixteen nuisance NIS found in Canada, which
was estimated at between $13.3 and $34.5 billion CDN per year. Canada remains highly vulnerable to new nuisance NIS, but available
manpower and financial resources appear insufficient to deal with this problem.
An erratum to this article is available at . 相似文献