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81.
Urbanisation of wildlife populations is a process with significant conservation and management implications. While urban areas can provide habitat for wildlife, some urbanised species eventually come into conflict with humans. Understanding the process and drivers of wildlife urbanisation is fundamental to developing effective management responses to this phenomenon. In Australia, flying-foxes (Pteropodidae) are a common feature of urban environments, sometimes roosting in groups of tens of thousands of individuals. Flying-foxes appear to be becoming increasingly urbanised and are coming into increased contact and conflict with humans. Flying-fox management is now a highly contentious issue. In this study we used monitoring data collected over a 15 year period (1998–2012) to examine the spatial and temporal patterns of association of spectacled flying-fox (Pteropus conspicillatus) roost sites (camps) with urban areas. We asked whether spectacled flying-foxes are becoming more urbanised and test the hypothesis that such changes are associated with anthropogenic changes to landscape structure. Our results indicate that spectacled flying-foxes were more likely to roost near humans than might be expected by chance, that over the period of the study the proportion of the flying-foxes in urban-associated camps increased, as did the number of urban camps. Increased urbanisation of spectacled flying-foxes was not related to changes in landscape structure or to the encroachment of urban areas on camps. Overall, camps tended to be found in areas that were more fragmented, closer to human habitation and with more urban land cover than the surrounding landscape. This suggests that urbanisation is a behavioural response rather than driven by habitat loss. 相似文献
82.
Background
Monitoring the functional connectivity between brain regions is becoming increasingly important in elucidating brain functionality in normal and disease states. Current methods of detecting networks in the recorded electroencephalogram (EEG) such as correlation and coherence are limited by the fact that they assume stationarity of the relationship between channels, and rely on linear dependencies. In contrast to diseases of the brain cortex (e.g. Alzheimer's disease), with motor disorders such as Parkinson's disease (PD) the EEG abnormalities are most apparent during performance of dynamic motor tasks, but this makes the stationarity assumption untenable. 相似文献83.
The importance of phenotypic plasticity and local adaptation in driving intraspecific variability in thermal niches of marine macrophytes 下载免费PDF全文
Climate change is driving the redistribution of species at a global scale and documenting and predicting species' responses to warming is a principal focus of contemporary ecology. When interpreting and predicting their responses to warming, species are generally treated as single homogenous physiological units. However, local adaptation and phenotypic plasticity can result in intraspecific differences in thermal niche. Therefore, population loss may also not only occur from trailing edges. In species with low dispersal capacity this will have profound impacts for the species as a whole, as local population loss will not be offset by immigration of warm tolerant individuals. Recent evidence from terrestrial forests has shown that incorporation of intraspecific variation in thermal niche is vital to accurately predicting species responses to warming. However, marine macrophytes (i.e. seagrasses and seaweeds) that form some of the world's most productive and diverse ecosystems have not been examined in the same context. We conducted a literature review to determine how common intraspecific variation in thermal physiology is in marine macrophytes. We find that 90% of studies identified (n = 42) found clear differences in thermal niche between geographically separated populations. Therefore, non‐trailing edge populations may also be vulnerable to future warming trends and given their limited dispersal capacity, such population loss may not be offset by immigration. We also explore how next generation sequencing (NGS) is allowing unprecedented mechanistic insight into plasticity and adaptation. We conclude that in the ‘genomic era’ it may be possible to link understanding of plasticity and adaptation at the genetic level through to changes in populations providing novel insights on the redistribution of populations under future climate change. 相似文献
84.
Integrated genetic and morphological data support eco‐evolutionary divergence of Angolan and South African populations of Diplodus hottentotus 下载免费PDF全文
M. P. Gwilliam A. C. Winkler W. M. Potts C. V. Santos W. H. H. Sauer P. W. Shaw N. J. McKeown 《Journal of fish biology》2018,92(4):1163-1176
The genus Diplodus presents multiple cases of taxonomic conjecture. Among these the D. cervinus complex was previously described as comprising three subspecies that are now regarded as separate species: Diplodus cervinus, Diplodus hottentotus and Diplodus omanensis. Diplodus hottentotus exhibits a clear break in its distribution around the Benguela Current system, prompting speculation that Angolan and South African populations flanking this area may be isolated and warrant formal taxonomic distinction. This study reports the first integrated genetic [mitochondrial (mt)DNA and nuclear microsatellite] and morphological (morphometric, meristic and colouration) study to assess patterns of divergence between populations in the two regions. High levels of cytonuclear divergence between the populations support a prolonged period of genetic isolation, with the sharing of only one mtDNA haplotype (12 haplotypes were fully sorted between regions) attributed to retention of ancestral polymorphism. Fish from the two regions were significantly differentiated at a number of morphometric (69·5%) and meristic (46%) characters. In addition, Angolan and South African fish exhibited reciprocally diagnostic colouration patterns that were more similar to Mediterranean and Indian Ocean congeners, respectively. Based on the congruent genetic and phenotypic diversity we suggest that the use of hottentotus, whether for full species or subspecies status, should be restricted to South African D. cervinus to reflect their status as a distinct species‐like unit, while the relationship between Angolan and Atlantic–Mediterranean D. cervinus will require further demo‐genetic analysis. This study highlights the utility of integrated genetic and morphological approaches to assess taxonomic diversity within the biogeographically dynamic Benguela Current region. 相似文献
85.
Fleur S. van Dijk Eline H. Zwikstra Sander R. Piersma Connie R. Jimenez Alice C. Morsman Mirjam H.H. van Roij Jonathan I.M.L. Verbeke Nick J. Shaw Carole McKeown Ann Dalton Gerard Pals 《American journal of human genetics》2009,85(4):521-527
Deficiency of cartilage-associated protein (CRTAP) or prolyl 3-hydroxylase 1(P3H1) has been reported in autosomal-recessive lethal or severe osteogenesis imperfecta (OI). CRTAP, P3H1, and cyclophilin B (CyPB) form an intracellular collagen-modifying complex that 3-hydroxylates proline at position 986 (P986) in the α1 chains of collagen type I. This 3-prolyl hydroxylation is decreased in patients with CRTAP and P3H1 deficiency. It was suspected that mutations in the PPIB gene encoding CyPB would also cause OI with decreased collagen 3-prolyl hydroxylation. To our knowledge we present the first two families with recessive OI caused by PPIB gene mutations. The clinical phenotype is compatible with OI Sillence type II-B/III as seen with COL1A1/2, CRTAP, and LEPRE1 mutations. The percentage of 3-hydroxylated P986 residues in patients with PPIB mutations is decreased in comparison to normal, but it is higher than in patients with CRTAP and LEPRE1 mutations. This result and the fact that CyPB is demonstrable independent of CRTAP and P3H1, along with reported decreased 3-prolyl hydroxylation due to deficiency of CRTAP lacking the catalytic hydroxylation domain and the known function of CyPB as a cis-trans isomerase, suggest that recessive OI is caused by a dysfunctional P3H1/CRTAP/CyPB complex rather than by the lack of 3-prolyl hydroxylation of a single proline residue in the α1 chains of collagen type I. 相似文献
86.
Summary To study the role of phagocytosis in periodontal tissues, internalization of fibronectin-coated latex beads by Gin-1 fibroblast populations was investigated. Demonstration of phagocytosis by internalization of beads was confirmed by immunofluorescence microscopy, electron microscopy, and flow-cytometry. The percent of cells phagocytosing beads measured by flow-cytometry was negligible at 4° and 23°C, but increased to approximately 17% at 37°C. As measured by automated image analysis, the percentage of phagocytosing cells increased linearly from 8 to 22 with increasing fibronectin concentration of the incubation solution from 30 ng to 300 g/ml. Similar linear increases in the percentage of phagocytosing cells were observed when beads were incubated with cells for periods ranging from 2 h to 2 days. To examine the role of the Arg-Gly-Asp receptor in mediating phagocytosis, fibronectin-coated beads were first coated with either Gly-Arg-Gly-Asp-Ser-Pro or Gly-Arg-Gly-Glu-Ser-Pro peptides at concentrations of 0.125, 0.5, and 1 mg/ml, or with control vehicle, and then incubated with cells. Phagocytosis was completely blocked at 1 mg/ml of the Gly-Arg-Gly-Asp-Ser-Pro peptide, but the Gly-Arg-Gly-Glu-Ser-Pro peptide showed no significant inhibition compared to control values. Blocking antibodies to the cell attachment domain of the fibronectin molecule also reduced the percentage of phagocytosing cells significantly. The data show that these phagocytic assays are sensitive enough to detect the influence of incubation temperature and time, cellular heterogeneity, ligand type, and ligand concentration on the percentage of phagocytosing cells. Further, the mechanisms which determine internalization of fibronectin-coated beads rely in part on the initial binding of ligand to the Arg-Gly-Asp receptor present on fibroblasts. 相似文献
87.
C C Vinson M Kanashiro A M Sebbenn T CR Williams S A Harris D H Boshier 《Heredity》2015,115(2):130-139
The impact of logging and subsequent recovery after logging is predicted to vary depending on specific life history traits of the logged species. The Eco-gene simulation model was used to evaluate the long-term impacts of selective logging over 300 years on two contrasting Brazilian Amazon tree species, Dipteryx odorata and Jacaranda copaia. D. odorata (Leguminosae), a slow growing climax tree, occurs at very low densities, whereas J. copaia (Bignoniaceae) is a fast growing pioneer tree that occurs at high densities. Microsatellite multilocus genotypes of the pre-logging populations were used as data inputs for the Eco-gene model and post-logging genetic data was used to verify the output from the simulations. Overall, under current Brazilian forest management regulations, there were neither short nor long-term impacts on J. copaia. By contrast, D. odorata cannot be sustainably logged under current regulations, a sustainable scenario was achieved by increasing the minimum cutting diameter at breast height from 50 to 100 cm over 30-year logging cycles. Genetic parameters were only slightly affected by selective logging, with reductions in the numbers of alleles and single genotypes. In the short term, the loss of alleles seen in J. copaia simulations was the same as in real data, whereas fewer alleles were lost in D. odorata simulations than in the field. The different impacts and periods of recovery for each species support the idea that ecological and genetic information are essential at species, ecological guild or reproductive group levels to help derive sustainable management scenarios for tropical forests. 相似文献
88.
Neural crest cells are highly migratory cells that give rise to many derivatives including peripheral ganglia, craniofacial structures and melanocytes. Neural crest cells migrate along defined pathways to their target sites, interacting with each other and their environment as they migrate. Cell adhesion molecules are critical during this process. In this review we discuss the expression and function of cell adhesion molecules during the process of neural crest migration, in particular cadherins, integrins, members of the immunoglobulin superfamily of cell adhesion molecules, and the proteolytic enzymes that cleave these cell adhesion molecules. The expression and function of these cell adhesion molecules and proteases are compared across neural crest emigrating from different axial levels, and across different species of vertebrates. 相似文献
89.
Cryptic species and parallel genetic structuring in Lethrinid fish: Implications for conservation and management in the southwest Indian Ocean 下载免费PDF全文
Amy J. E. Healey Niall J. McKeown Amy L. Taylor Jim Provan Warwick Sauer Gavin Gouws Paul W. Shaw 《Ecology and evolution》2018,8(4):2182-2195
Analysis of genetic variation can provide insights into ecological and evolutionary diversification which, for commercially harvested species, can also be relevant to the implementation of spatial management strategies and sustainability. In comparison with other marine biodiversity hot spots, there has been less genetic research on the fauna of the southwest Indian Ocean (SWIO). This is epitomized by the lack of information for lethrinid fish, which support socioeconomically important fisheries in the region. This study combines comparative phylogeographic and population genetic analyses with ecological niche modeling to investigate historical and contemporary population dynamics of two species of emperor fish (Lethrinus mahsena and Lethrinus harak) across the SWIO. Both species shared similarly shallow phylogeographic patterns and modeled historical (LGM) habitat occupancies. For both species, allele frequency and kinship analyses of microsatellite variation revealed highly significant structure with no clear geographical pattern and nonrandom genetic relatedness among individuals within samples. The genetic patterns for both species indicate recurrent processes within the region that prevent genetic mixing, at least on timescales of interest to fishery managers, and the potential roles of recruitment variability and population isolation are discussed in light of biological and environmental information. This consistency in both historical and recurrent population processes indicates that the use of model species may be valuable in management initiatives with finite resources to predict population structure, at least in cases wherein biogeographic and ecological differences between taxa are minimized. Paradoxically, mtDNA sequencing and microsatellite analysis of samples from the Seychelles revealed a potential cryptic species occurring in sympatry with, and seemingly morphologically identical to, L. mahsena. BLAST results point to the likely misidentification of species and incongruence between voucher specimens, DNA barcodes, and taxonomy within the group, which highlights the utility and necessity of genetic approaches to characterize baseline biodiversity in the region before such model‐based methods are employed. 相似文献
90.