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51.
B. Hausdorf 《Journal of Biogeography》2000,27(2):379-390
Aim Reconstruction of the historical biogeography of the Limacoidea sensu lato (including the Staffordiidae, Dyakiidae, Gastrodontoidea, Parmacelloidea, Zonitidae, Helicarionoidea and Limacoidea). Evaluation of the relative importance of dispersal and its consequences. Location World‐wide. Methods Weighted ancestral area analysis. Results The ancestral areas of the individual clades have been delimited using weighted ancestral area analysis and a sequence of possible vicariance and dispersal events has been suggested. The results of the ancestral area analysis have tentatively been correlated with Cretaceous and Tertiary palaeogeography. The widely overlapping distribution patterns of several families of the Limacoidea testify to extensive dispersal events. Dispersal capacity of land snails is correlated with body size. The significant negative correlation between body size and distribution area size corroborates the importance of passive dispersal for the evolution of the distribution patterns. Main conclusions The existence of extensive dispersal events of poor active dispersers like land snails diminishes the importance of recent distribution patterns for the reconstruction of palaeogeography. On the other hand, dispersal ensures that biogeographical data reflect the geographical configurations at a given time and renders the use of palaeobiogeographic data for the reconstruction of palaeogeographic configurations of the respective age possible. 相似文献
52.
Caio Maximino 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2008,194(11):939-944
The fast-start is an ecologically relevant behavior pattern in fishes. The present article analyses the distribution of five
continuous kinematic traits (latency for response initiation, time to maximum angular velocity, time to maximum displacement
velocity, maximum angular velocity, and maximum displacement velocity) in eight of the eleven species described in Eaton (66:65–81,
1977). Phylogenetic generalized least square estimation of ancestor states demonstrated evolutionary changes in maximum angular
velocity and maximum displacement velocity, consistent with species differences in the same variables. These changes in maximum
velocity are also correlated (phylogenetically independent contrasts) with the mean body sizes of all species, pointing to
the possibility that body size was an evolutionary constraint on maximum velocities. The conservation of the other traits
suggest that they are mainly constrained by neural control, and a trade-off between neural and body size-constraints is proposed
ex hypothesi.
An erratum to this article can be found at 相似文献
53.
Future uses of pollen analysis must include plant macrofossils 总被引:8,自引:0,他引:8
54.
55.
Traditional medicine markets are provided with medicinal plant material throughout the year, however, internal (e.g. plant age, genetic variability and differential expression of genes) and external factors (e.g. water and nutrient availability, rainfall, photoperiod and herbivory), affect secondary metabolite production in plants. In this study, seasonal variability in metabolite production in Curtisia dentata trees from two geographically separated regions in South Africa are compared. NMR analysis of C. dentata stem bark samples yielded spectral data which were processed in MestReNova to perform multivariate data analysis using Soft Independent Modeling of Class Analogy (SIMCA) software. This study shows that there are not only seasonal, regional and yearly differences in secondary metabolite production in C. dentata trees, but that production patterns of hydrophilic and lipophilic chemical compounds in individual trees also vary. Sucrose, isoeugenol and betulinic acid have been used in a targeted analysis to show the variation in individual compounds in the individual trees as a response to seasonal and geographical differences. Therefore, the season and year, as well as the region, harvesting site and specific trees from which plant material is collected affect the concentrations of chemical compounds extracted from C. dentata stem bark for the preparation of remedies. 相似文献
56.
SHARON BARUCH-MORDO STEWART W. BRECK KENNETH R. WILSON DAVID M. THEOBALD 《The Journal of wildlife management》2008,72(8):1853-1862
Abstract: Management and conservation of large carnivores increasingly includes conflicts with humans. Consequently, a greater understanding of spatiotemporal trends of conflicts is needed to efficiently allocate resources and apply targeted management. Therefore, we examined spatial and temporal distribution of American black bear (Ursus americanus; hereafter, bear)-human conflicts in Colorado, USA, related to 3 conflict types (agriculture operations, human development, and road kills). We used the Getis-Ord Gi* spatial clustering statistic to describe location and assess magnitude of bear-human conflicts in Colorado during 1986–2003 and investigated temporal trends of bear-human conflicts by type. Bear-human conflicts showed distinct spatial clustering by type, and areas of high clustering overlapped conflict types. Clustering for agriculture operations conflicts had the largest overall Gi* value and overlapped counties with high sheep production. Both human development and road-kill conflict clusters were high in areas of high-quality oak (Quercus spp.)—shrub habitat in the central and southern portions of Colorado's Front Range region and near the city of Durango in southwestern Colorado. Bear-human conflicts varied by year and type but overall increased during the 18 years. Summed across years, most conflicts were related to agriculture (32%), followed by road kills (27%) and human development (24%). The greatest proportion of agriculture operations-related conflicts (76%), human development-related conflicts (36%), and road kills (47%) occurred in 1988, 1999, and 2003, respectively. Considering that bear-human conflicts in Colorado increased over time and will likely continue to increase, we suggest wildlife managers improve data collection by obtaining detailed location data, categorizing conflict types uniformly, and applying conflict regulations consistently to strengthen inference of similar analyses. We also suggest that managers target efforts to mitigate damage by focusing on areas with high clustering of conflicts. 相似文献
57.
D. Pangallo K. Chovanov H. Drahovska F. De Leo C. Urzì 《International biodeterioration & biodegradation》2009,63(7):868-872
The aim of this work was the evaluation of fluorescence ITS-PCR (f-ITS) as a molecular tool to analyze the microbial community involved in the biodeterioration of cultural heritage surfaces. As a case study we analyzed by f-ITS ninety-two bacterial strains isolated from a medieval fresco and the surrounding air environment. The internal transcribed spacer between the 16S and 23S rRNA genes was amplified, and then the fluorescently labeled PCR products were separated by capillary electrophoresis. Bacterial strains were identified by 16S rDNA sequencing. The f-ITS electropherograms showed different profiles coherent with the affiliation of the strains at the genus and species levels. Among the isolates obtained from the fresco surface, those belonging to the genus Bacillus were the most prevailing exhibiting 8 different f-ITS profiles. The airborne bacilli exhibited only 2 of these 8 profiles. Staphylococcus were mostly isolated from air and produced 4 different profiles. Pseudomonas isolates presented 3 different profiles, and one of them was typical of Pseudomonas putida. Members of the other genera produced their distinctive profiles. Our results show that f-ITS is a promising molecular tool for the rapid selection and clustering of strains isolated from different sources. 相似文献
58.
F. MONTEALEGRE‐Z 《Journal of evolutionary biology》2009,22(2):355-366
Male katydids (Orthoptera: Tettigoniidae) produce mating calls by rubbing the wings together, using specialized structures in their forewings (stridulatory file, scraper and mirror). A large proportion of species (ca. 66%) reported in the literature produces ultrasonic signals as principal output. Relationships among body size, generator structures and the acoustic parameters carrier frequency (fc) and pulse duration (pd), were studied in 58 tropical species that use pure‐tone signals. A comparative analysis, based on the only available katydid phylogeny, shows how changes in sound generator form are related to changes in fc and pd. Anatomical changes of the sound generator that might have been selected via fc and pd are mirror size, file length and number of file teeth. Selection for structures of the stridulatory apparatus that enhance wing mechanics via file‐teeth and scraper morphology was crucial in the evolution of ultrasonic signals in the family Tettigoniidae. 相似文献
59.
Contrary to theoretical predictions, female 2‐spot ladybirds (Adalia bipunctata) mate many more times than necessary to maintain high fertilisation success and may gain through the acquisition of material or genetic benefits. In order to investigate this mating system in detail, microsatellite markers have been isolated using a modified enrichment technique. Thirty‐nine loci were successfully amplified by polymerase chain reaction (PCR), of which only two were monomorphic. Detailed characterization of ten loci revealed very high levels of polymorphism. These markers are likely to be invaluable tools with which to study population genetics and patterns of paternity in this species. 相似文献
60.
This paper examines family resemblance for five anthropometric measurements (height, weight, triceps skinfold, upper arm circumference relaxed [UACR] and flexed [UACF] and for systolic and diastolic blood pressure in a group of adult Caribbean islanders of primarily African ancestry. Six hypotheses about family resemblance are tested by using path analysis and likelihood ratios. Significant intergenerational transmission is found only for height and UACR. For weight, UACF, and diastolic blood pressure, non-transmissible sibling resemblance is the primary component of family resemblance, although significant marital resemblance exists for diastolic blood pressure. Triceps skinfold and systolic blood pressure show no evidence of any family resemblance. Although results for highly heritable traits such as height are comparable to reports from other populations, measurements with a large contribution from common family environment or residual environmental effects, such as triceps skinfold or blood pressure, have much lower family resemblance in this population than in other populations. We hypothesize that this difference is due to the fact that adult children and their parents do not share a common household in this culture and to the presence of major nonfamilial environmental factors contributing to obesity and hypertension in this population. 相似文献