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Michael J. Somers - One of the best experts on this subject based on the ideXlab platform.
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Diet of Otters (Lutra lutra) in various habitat types in the Pannonian biogeographical region compared to other regions of Europe.
PeerJ, 2016Co-Authors: József Lanszki, István Lehoczky, Antoinette Kotze, Michael J. SomersAbstract:Knowledge of the effect of habitat type and region on diet and feeding behaviours of a species facilitates a better understanding of factors impacting populations, which contributes to effective conservation management. Using spraint analysis and relative frequency of occurrence data from the literature, we described the dietary patterns of Eurasian Otters (Lutra lutra) in 23 study sites within the Pannonian biogeographical region in Hungary. Our results indicated that diet composition varied by habitat type and is therefore context dependant. The differences among habitat types were however lower than expected. We noticed a decline in the fish consumption with a concomitant increase in trophic niche breadth and amphibian consumption in rivers, ponds (fish farms), backwaters, marshes and small watercourses. The main differences in diet were not attributed to the consumption of primary and secondary food types (fish and amphibians), but rather to differences in other, less important food types (mammals, birds). Using hierarchical cluster analysis, rivers and ponds could clearly be separated from other habitat types. We found the main fish diet of Otters in most of these areas consisted of small (
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diet of Otters lutra lutra in various habitat types in the pannonian biogeographical region compared to other regions of europe
PeerJ, 2016Co-Authors: József Lanszki, István Lehoczky, Antoinette Kotze, Michael J. SomersAbstract:Knowledge of the effect of habitat type and region on diet and feeding behaviours of a species facilitates a better understanding of factors impacting populations, which contributes to effective conservation management. Using spraint analysis and relative frequency of occurrence data from the literature, we described the dietary patterns of Eurasian Otters (Lutra lutra) in 23 study sites within the Pannonian biogeographical region in Hungary. Our results indicated that diet composition varied by habitat type and is therefore context dependant. The differences among habitat types were however lower than expected. We noticed a decline in the fish consumption with a concomitant increase in trophic niche breadth and amphibian consumption in rivers, ponds (fish farms), backwaters, marshes and small watercourses. The main differences in diet were not attributed to the consumption of primary and secondary food types (fish and amphibians), but rather to differences in other, less important food types (mammals, birds). Using hierarchical cluster analysis, rivers and ponds could clearly be separated from other habitat types. We found the main fish diet of Otters in most of these areas consisted of small (<100 g), eurytopic, littoral and non-native, mostly invasive species. Dietary studies from 91 sites in six European biogeographical regions showed that fish are consumed most frequently in the Atlantic and Boreal, less in the Continental and Pannonian, and least in the Alpine and Mediterranean regions. Comparative analysis indicated that the Mediterranean region (with frequent crayfish consumption) and Alpine region (frequent amphibian consumption) cluster separate from the other regions.
Larry Wos - One of the best experts on this subject based on the ideXlab platform.
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Otter proofs in Tarskian geometry
2015Co-Authors: Michael Beeson, Larry WosAbstract:Abstract. We report on a project to use Otter to find proofs of the theorems in Tarskian geometry proved in Szmielew’s part (Part I) of [9]. These theorems start with fundamental properties of betweenness, and end with the development of geometric definitions of addition and multiplication that permit the representation of models of geometry as planes over Euclidean fields, or over real-closed fields in the case of full continuity. They include the four challenge problems left unsolved by Quaife, who two decades ago found some Otter proofs in Tarskian geometry (solving challenges issued in [15]). Quaife’s four challenge problems were: every line segment has a midpoint; every segment is the base of some isosceles triangle; the outer Pasch ax-iom (assuming inner Pasch as an axiom); and the first outer connectivity property of betweenness. These are to be proved without any parallel ax-iom and without even line-circle continuity. These are difficult theorems, the first proofs of which were the heart of Gupta’s Ph. D. thesis under Tarski. Otter proved them all in 2012. Our success, we argue, is due to improvements in techniques of automated deduction, rather than to increases in computer speed and memory. The theory of Hilbert (1899) can be translated into Tarski’s language, in-terpreting lines as pairs of distinct points, and angles as ordered triples of non-collinear points. Under this interpretation, the axioms of Hilbert ei-ther occur among, or are easily deduced from, theorems in the first 11 (of 16) chapters of Szmielew. We have found Otter proofs of all of Hilbert’s axioms from Tarski’s axioms (i.e. through Satz 11.49 of Szmielew, plus Satz 12.11). Narboux and Braun have recently checked these same proofs in Coq.
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Otter proofs in tarskian geometry
International Joint Conference on Automated Reasoning, 2014Co-Authors: Michael Beeson, Larry WosAbstract:We report on a project to use Otter to find proofs of the theorems in Tarskian geometry proved in Szmielew’s part (Part I) of [9]. These theorems start with fundamental properties of betweenness, and end with the development of geometric definitions of addition and multiplication that permit the representation of models of geometry as planes over Euclidean fields, or over real-closed fields in the case of full continuity. They include the four challenge problems left unsolved by Quaife, who two decades ago found some Otter proofs in Tarskian geometry (solving challenges issued in [15]).
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Otter the cade 13 competition incarnations
Journal of Automated Reasoning, 1997Co-Authors: William Mccune, Larry WosAbstract:This article discusses the two incarnations of Otter entered in the CADE-13 Automated Theorem Proving System Competition. Also presented are some historical background, a summary of applications that have led to new results in mathematics and logic, and a general discussion of Otter.
József Lanszki - One of the best experts on this subject based on the ideXlab platform.
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Diet of Otters (Lutra lutra) in various habitat types in the Pannonian biogeographical region compared to other regions of Europe.
PeerJ, 2016Co-Authors: József Lanszki, István Lehoczky, Antoinette Kotze, Michael J. SomersAbstract:Knowledge of the effect of habitat type and region on diet and feeding behaviours of a species facilitates a better understanding of factors impacting populations, which contributes to effective conservation management. Using spraint analysis and relative frequency of occurrence data from the literature, we described the dietary patterns of Eurasian Otters (Lutra lutra) in 23 study sites within the Pannonian biogeographical region in Hungary. Our results indicated that diet composition varied by habitat type and is therefore context dependant. The differences among habitat types were however lower than expected. We noticed a decline in the fish consumption with a concomitant increase in trophic niche breadth and amphibian consumption in rivers, ponds (fish farms), backwaters, marshes and small watercourses. The main differences in diet were not attributed to the consumption of primary and secondary food types (fish and amphibians), but rather to differences in other, less important food types (mammals, birds). Using hierarchical cluster analysis, rivers and ponds could clearly be separated from other habitat types. We found the main fish diet of Otters in most of these areas consisted of small (
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diet of Otters lutra lutra in various habitat types in the pannonian biogeographical region compared to other regions of europe
PeerJ, 2016Co-Authors: József Lanszki, István Lehoczky, Antoinette Kotze, Michael J. SomersAbstract:Knowledge of the effect of habitat type and region on diet and feeding behaviours of a species facilitates a better understanding of factors impacting populations, which contributes to effective conservation management. Using spraint analysis and relative frequency of occurrence data from the literature, we described the dietary patterns of Eurasian Otters (Lutra lutra) in 23 study sites within the Pannonian biogeographical region in Hungary. Our results indicated that diet composition varied by habitat type and is therefore context dependant. The differences among habitat types were however lower than expected. We noticed a decline in the fish consumption with a concomitant increase in trophic niche breadth and amphibian consumption in rivers, ponds (fish farms), backwaters, marshes and small watercourses. The main differences in diet were not attributed to the consumption of primary and secondary food types (fish and amphibians), but rather to differences in other, less important food types (mammals, birds). Using hierarchical cluster analysis, rivers and ponds could clearly be separated from other habitat types. We found the main fish diet of Otters in most of these areas consisted of small (<100 g), eurytopic, littoral and non-native, mostly invasive species. Dietary studies from 91 sites in six European biogeographical regions showed that fish are consumed most frequently in the Atlantic and Boreal, less in the Continental and Pannonian, and least in the Alpine and Mediterranean regions. Comparative analysis indicated that the Mediterranean region (with frequent crayfish consumption) and Alpine region (frequent amphibian consumption) cluster separate from the other regions.
Michael J. Murray - One of the best experts on this subject based on the ideXlab platform.
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Aquatic Adaptation and Depleted Diversity: A Deep Dive into the Genomes of the Sea Otter and Giant Otter
Molecular biology and evolution, 2019Co-Authors: Annabel C. Beichman, Michael J. Murray, Klaus-peter Koepfli, William J. Murphy, Pasha Dobrynin, Sergei Kliver, M. T. Tinker, Jeremy Johnson, Kerstin Lindblad-tohAbstract:Despite its recent invasion into the marine realm, the sea Otter (Enhydra lutris) has evolved a suite of adaptations for life in cold coastal waters, including limb modifications and dense insulating fur. This uniquely dense coat led to the near-extinction of sea Otters during the 18th-20th century fur trade and an extreme population bottleneck. We used the de novo genome of the southern sea Otter (E. l. nereis) to reconstruct its evolutionary history, identify genes influencing aquatic adaptation, and detect signals of population bottlenecks. We compared the genome of the southern sea Otter with the tropical freshwater-living giant Otter (Pteronura brasiliensis) to assess common and divergent genomic trends between Otter species, and with the closely related northern sea Otter (E. l. kenyoni) to uncover population-level trends. We found signals of positive selection in genes related to aquatic adaptations, particularly limb development and polygenic selection on genes related to hair follicle development. We found extensive pseudogenization of olfactory receptor genes in both the sea Otter and giant Otter lineages, consistent with patterns of sensory gene loss in other aquatic mammals. At the population level, the southern sea Otter and the northern sea Otter showed extremely low genomic diversity, signals of recent inbreeding, and demographic histories marked by population declines. These declines may predate the fur trade and appear to have resulted in an increase in putatively deleterious variants that could impact the future recovery of the sea Otter.
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Veterinary Medicine and Sea Otter Conservation
Sea Otter Conservation, 2015Co-Authors: Michael J. MurrayAbstract:Veterinarians and veterinary medicine, in general, have historically played, and continue to play, an important role in the efforts to understand sea Otters and assure the conservation of free-ranging sea Otter populations. There are, however, important differences between the “traditional” doctor–patient–client relationship paradigm associated with the health management of individual animals, and the manner in which health and disease are evaluated and interpreted in populations of animals. It comes as no surprise that animals in the wild die from one or combinations of a myriad of causes. Therefore, if one examines a large enough number of animals, you will find some that are, in fact, critically ill and dying. It is important to recognize that the veterinarian’s role in conservation medicine is not to “cure every sick sea Otter,” but rather to provide insight into the etiopathogenesis, the epidemiology, and the implications of these diseases. This information may then be integrated into the bigger population picture involving wildlife ecology, natural history, environmental factors, and demography, all of which are critically important in the understanding, and therefore the preservation, of sea Otter populations.
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Gene transcription in sea Otters (Enhydra lutris); development of a diagnostic tool for sea Otter and ecosystem health.
Molecular ecology resources, 2011Co-Authors: Lizabeth Bowen, B E Ballachey, James L. Bodkin, Michael J. Murray, Martin Haulena, A. Keith Miles, Judy Tuttle, William Van Bonn, Lance Adams, James A. EstesAbstract:Gene transcription analysis for diagnosing or monitoring wildlife health requires the ability to distinguish pathophysiological change from natural variation. Herein, we describe methodology for the development of quantitative real-time polymerase chain reaction (qPCR) assays to measure differential transcript levels of multiple immune function genes in the sea Otter (Enhydra lutris); sea Otter-specific qPCR primer sequences for the genes of interest are defined. We establish a ‘reference’ range of transcripts for each gene in a group of clinically healthy captive and free-ranging sea Otters. The 10 genes of interest represent multiple physiological systems that play a role in immuno-modulation, inflammation, cell protection, tumour suppression, cellular stress response, xenobiotic metabolizing enzymes, antioxidant enzymes and cell‐cell adhesion. The cycle threshold (CT) measures for most genes were normally distributed; the complement cytolysis inhibitor was the exception. The relative enumeration of multiple gene transcripts in simple peripheral blood samples expands the diagnostic capability currently available to assess the health of sea Otters in situ and provides a better understanding of the state of their environment.
John K. Wenburg - One of the best experts on this subject based on the ideXlab platform.
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Characterization of eight microsatellite loci in Sea Otter, Enhydra lutris, and cross-species amplification in other Mustelidae
Conservation Genetics, 2008Co-Authors: Eric J. Kretschmer, Jeffrey B. Olsen, John K. WenburgAbstract:Herein we describe the development of eight microsatellite markers for the northern sea Otter, Enhydra lutris kenyoni. A total of 45 primer pairs were developed and screened from enriched AAAT, CATC, TACA, and TAGA libraries derived from genomic DNA of E. lutris kenyoni. Of these, eight amplified successfully. The average observed heterozygosity, expected heterozygosity, and number of alleles per locus was 0.506, 0.537, and 3.4, respectively. These eight loci were tested across three additional genra; Vulpes lagopus, Martes americana, and Mustela nivalis. Based on the success of our results these loci will be useful for future studies across all sub-species of E. lutris.
