13 research outputs found

    Morphometric differences in the grasshopper Cornops aquaticum (Bruner, 1906) from South America and South Africa

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    The semi-aquatic grasshopper Cornops aquaticum is native to South America and inhabits lowlands from southern Mexico to Central Argentina and Uruguay. It is host-specific to aquatic plants in the genera Eichhornia and Pontederia. A quarantine population has existed in South Africa for 10 y, and it is planned to release it there as a biological control agent of water hyacinth, E. crassipes. Various studies of C. aquaticum are coordinated under HICWA (www.mpil-ploen.mpg.de). This paper compares the morphometry of the release population and 11 native populations in South America. We tested four hypotheses: 1) South African and South American populations of C. aquaticum differ in morphology; 2) the South African laboratory population is more similar to other isolated populations in South America than to nonisolated populations; 3) morphology differs across sites; 4) morphology differs with host plant. South African populations differed from continental nonisolated populations, but not from continental isolated ones. Isolated populations presented smaller individuals than nonisolated, but there was also a change in male morphology: while in nonisolated populations male wing length was similar to their body length, in isolated populations, male wings were smaller than body length. Females were larger when on Eicchornia azurea than on E. crassipes, while males presented larger wings than their body on E. azurea, and similar lengths on E. crassipes. These morphological changes may have resulted from phenotypic plasticity, selection for small size, or because of a loss of genetic diversity in quantitative traits.Fil: Adis, Joachim. Institute for Limnology; AlemaniaFil: Sperber, Carlos F. Universidade Federal de Viçosa; BrasilFil: Brede, Edward G. Institute for Limnology; AlemaniaFil: Capello, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Franceschini, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Hill, Martin. Rhodes University; SudáfricaFil: Lhano, Marcos G. Universidade Federal de Viçosa; BrasilFil: Marques, Marinê. A;z M.. Universidade Federal de Mato Grosso; BrasilFil: Nunes, Ana L.. Muséu Paraense Emílio Goeldi; BrasilFil: Polar, Perry. CAB International; Trinidad y Tobag

    Financial Systems and Industrial Policy in Germany and Great Britain: The Limits of Convergence

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    Significant benefits of AIP testing and clinical screening in familial isolated and young-onset pituitary tumors

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    Context Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are responsible for a subset of familial isolated pituitary adenoma (FIPA) cases and sporadic pituitary neuroendocrine tumors (PitNETs). Objective To compare prospectively diagnosed AIP mutation-positive (AIPmut) PitNET patients with clinically presenting patients and to compare the clinical characteristics of AIPmut and AIPneg PitNET patients. Design 12-year prospective, observational study. Participants & Setting We studied probands and family members of FIPA kindreds and sporadic patients with disease onset ≤18 years or macroadenomas with onset ≤30 years (n = 1477). This was a collaborative study conducted at referral centers for pituitary diseases. Interventions & Outcome AIP testing and clinical screening for pituitary disease. Comparison of characteristics of prospectively diagnosed (n = 22) vs clinically presenting AIPmut PitNET patients (n = 145), and AIPmut (n = 167) vs AIPneg PitNET patients (n = 1310). Results Prospectively diagnosed AIPmut PitNET patients had smaller lesions with less suprasellar extension or cavernous sinus invasion and required fewer treatments with fewer operations and no radiotherapy compared with clinically presenting cases; there were fewer cases with active disease and hypopituitarism at last follow-up. When comparing AIPmut and AIPneg cases, AIPmut patients were more often males, younger, more often had GH excess, pituitary apoplexy, suprasellar extension, and more patients required multimodal therapy, including radiotherapy. AIPmut patients (n = 136) with GH excess were taller than AIPneg counterparts (n = 650). Conclusions Prospectively diagnosed AIPmut patients show better outcomes than clinically presenting cases, demonstrating the benefits of genetic and clinical screening. AIP-related pituitary disease has a wide spectrum ranging from aggressively growing lesions to stable or indolent disease course

    Genetic diversity, population structure and gene flow in native populations of a proposed biocontrol agent (Cornops aquaticum)

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    The semiaquatic grasshopper Cornops aquaticum is native to South America, with a distribution as far south as the Argentinean pampas and as far north as the Gulf of Mexico. This grasshopper is being proposed as a form of biological control agent for the invasive aquatic macrophyte (Eichhornia crassipes) in South Africa. The results of a molecular study (six microsatellite loci) conducted on 11 C. aquaticum populations is presented. Unlike in contiguous mainland South American populations, we found genetic diversity to be lowest in a South African quarantine population, with reduced values in two other isolated populations from South America. In addition, F-st/R-st/analysis of molecular variance and Bayesian cluster analysis suggested high levels of connectivity between mainland populations. The implications of these findings and their relationship to those of a recent morphological study suggest that the suitability of C. aquaticum as a form of biocontrol might be unpredictable at best

    Large variations in the ratio of effective breeding and census population sizes between two species of pond-breeding anurans

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    The viability of wild populations is frequently assessed by monitoring adult census sizes (N-c). This approach is particularly useful for pond-breeding amphibians, because assemblages during the breeding season are relatively easy to detect and count. However, it is the genetic effective population size (N-e) or surrogates such as effective breeding population size (N-b) that are of primary importance for long-term viability. Although N-c estimates of one anuran amphibian (Bufo bufo) in Britain were much larger than those of another (Rana temporaria) at the same sites, the ratios of N-b to N-c were much smaller in B. bufo than in R. temporaria. These differences were sufficiently great as to reverse the effective size order at one site, such that N-b for R. temporaria was larger than that for B. bufo. Differences in adult sex ratios at breeding sites probably contributed to lower N-b values in B. bufo populations compared with those of R. temporaria. The relationship of N-b to N-c can therefore vary dramatically even between similar species, to the extent that just monitoring N-c can give misleading impressions of relative effective breeding sizes and thus of population viability. It will be increasingly important to estimate N-e or N-b in wildlife populations for assessment of conservation prioritie

    Consistently different levels of genetic variation across the European ranges of two anurans, Bufo bufo and Rana temporaria

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    We compared the genetic diversities across eight microsatellite loci of two widespread anurans, Bufio bufo and Rana temporaria, at multiple sites across their western and central European ranges. Bufo bufo consistently exhibited less genetic diversity than R. temporaria. Our evidence infers that this difference is unlikely to be a feature of the specific marker loci used, nor is it a probable consequence of the different phylogeographic histories of B. bufo and R. temporaria. No recent bottlenecks were observed in B. bufo or R. temporaria populations. Both species showed similar levels of differentiation across their European range as estimated by F-statistics, but whereas R. temporaria exhibited isolation by distance effects, B. bufo did not. We suggest that distinct autecological features of the two species are the most likely explanation of the diversity differences, especially more limited historical gene flow among Bufio compared with Rana populations

    Polymerase chain reaction primers for microsatellite loci in the Common Toad Bufo bufo

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    The Common Toad Bufo bufo is a wide-ranging species, with a distribution encompassing much of Europe and Asia. Few molecular studies have been undertaken on this species, and only one polymorphic microsatellite locus has been identified. Therefore, little is known about the genetic variability within and between B. bufo populations. The value of such information is essential for monitoring the species and its environment. This paper reports the characterization of 15 B. bufo microsatellite loci using individuals from a Spanish and UK sample

    PCR primers for microsatellite loci in a Madagascan waterbird, the Sakalava Rail (Amaurornis olivieri)

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    We isolated 76 microsatellite loci from the Sakalava rail (Amaurornis olivieri) genome. These were tested in 30 individuals from six sites (in three regions) across the species’ range in Madagascar. Thirty-four of the 76 loci produced unambiguous polymorphic markers, with mean H e = 0.544 (range 0.0678–0.885), mean H o = 0.430 (range 0.0400–0.767) and mean N a = 4.59 (range 2–10). In addition, we tested all primers for amplification in the Wood rail, Canirallus kioloides (N = 3) and the Bemaraha rail, Canirallus sp. nov (N = 3). Twelve of the loci produced successful amplification with eight loci showing polymorphism

    Data from: Contrasting genetic diversity and population structure among three sympatric Madagascan shorebirds: parallels with rarity, endemism, and dispersal

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    Understanding the relative contributions of intrinsic and extrinsic factors to population structure and genetic diversity is a central goal of conservation and evolutionary genetics. One way to achieve this is through comparative population genetic analysis of sympatric sister taxa, which allows evaluation of intrinsic factors such as population demography and life history while controlling for phylogenetic relatedness and geography. We used ten conserved microsatellites to explore the population structure and genetic diversity of three sympatric and closely related plover species in southwestern Madagascar: Kittlitz's plover (Charadrius pecuarius), white-fronted plover (C. marginatus), and Madagascar plover (C. thoracicus). Bayesian clustering revealed strong population structure in the rare and endemic Madagascar plover, intermediate population structure in the white-fronted plover, and no detectable population structure in the geographically widespread Kittlitz's plover. In contrast, allelic richness and heterozygosity were highest for the Kittlitz's plover, intermediate for the white-fronted plover and lowest for the Madagascar plover. No evidence was found in support of the “watershed mechanism” proposed to facilitate vicariant divergence of Madagascan lemurs and reptiles, which we attribute to the vagility of birds. However, we found a significant pattern of genetic isolation by distance among populations of the Madagascar plover, but not for the other two species. These findings suggest that interspecific variation in rarity, endemism, and dispersal propensity may influence genetic structure and diversity, even in highly vagile species
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