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101.
The rich get richer: Invasion risk across North America from the aquarium pathway under climate change 下载免费PDF全文
Aim
To evaluate how the establishment risk of freshwater fish species from the aquarium trade will change under a climate change scenario forecast for the year 2050.Location
North America.Methods
In order to estimate changes in the magnitude of risk across geography and across different species in the aquarium pathway, we considered an integrated approach to modelling the probability of establishment, which simultaneously included proxies of propagule pressure, environmental variables, species traits and interactions between environment and traits. We then used the parameters of our model to predict how the risk of establishment will change under a scenario of climate change forecast for the year 2050.Results
Our joint model performed better than submodels, suggesting that combining all components is worthwhile. The most predictive factors were precipitation, maximum temperature tolerance, maximum fish length and minimum temperature. Our joint model forecasted a 40% increase in the average risk of establishment by 2050 in the United States. In contrast to our expectations, the absolute establishment risk associated with this pathway remained very low for the entire suite of species in the aquarium trade in northern regions, such as Quebec, Canada. Instead, Florida, which has one of the highest current risks of establishment, was also forecasted to have the greatest absolute risk increase.Main conclusions
Our methodology for risk assessment allows invasive species management strategies to consider entire suites of species at a time and to forecast establishment risk for each species and location. While the aquarium pathway is likely to become more important for the United States, the Quebec government should prioritize other pathways of introduction in its exotic invasive species strategy. Our approach can be extended to be applied to different sets of species pertaining to the same or different pathways.102.
Genetic examination of the type specimen of Ulva australis suggests that it was introduced to Australia 下载免费PDF全文
‘Ana‐aosa’, one of the most common marine green algae in Japan, was described as Ulva pertusa Kjellman in 1897 from Hakodate in northern Japan. Ulva pertusa was considered to be a temperate species, with its native distributional range restricted to northeastern Asia. Although this species has been reported from various regions outside northeastern Asia, these records have been explained as non‐indigenous populations. Recently, on the basis of genetic data and nomenclatural priority, U. pertusa was synonymized with U. australis Areschoug, a species described in 1851 from specimens collected in South Australia. Based on genetic studies, Australian populations identified as U. pertusa had been considered to have originated from Japan. However, the published genetic data on U. australis in Australia have been based only on recent collections and no historical specimens have been examined. We tested the hypothesis that native (true) U. australis is an independent species of very similar morphology to U. pertusa, but that its natural domination of shoreline habitats has been suppressed by introduced populations of U. pertusa from Asia. In the present study, we extracted DNA from the type specimen of U. australis housed in the Swedish Museum of Natural History (S) and obtained DNA sequences of the chloroplast rbcL gene and the nuclear rDNA ITS2 region. Our results show that U. australis and U. pertusa are genetically virtually identical, confirming that U. pertusa is a synonym of U. australis. This suggests that the introduction of U. australis to Australia occurred by the middle of the 19th century, when the type was collected and before there was a direct shipping route between Japan and Australia. We speculate that the introduction of U. australis to Australia occurred as a secondary introduction from non‐indigenous populations in northeastern Asia, but not directly from Japan. 相似文献
103.
《The Australian journal of anthropology》2018,29(1):53-69
In response to the over‐representation of Australian Indigenous women in the criminal justice system, culturally relevant and gender‐specific bail programs operate in several Queensland Indigenous sentencing courts or Murri Courts. Queensland Murri Courts are a specialist criminal law practice, which includes Elders and respected persons of Community Justice Groups in the sentencing process of Indigenous peoples. This paper explores the role of one gender‐specific bail program, Women's Yarning or Talking Circles, in one Southeast Queensland Murri Court. Women's Yarning Circles aspire to create an Indigenous‐centred space outside of court proceedings where defendants and Community Justice Group members of the same gender can build a rapport. Gender‐specific bail programs aim to recognise the intricacies of an Indigenous woman's intersectional identity and the diverse needs of each defendant that comes before the Murri Court. 相似文献
104.
Darrell A. Posey Graham Dutfield Kristina Plenderleith 《Biodiversity and Conservation》1995,4(8):892-902
Scientists find themselves working more and more with indigenous, traditional and local communities in all aspects of their collections and investigations. Indigenous knowledge has become increasingly important in research while at the same time local communities have become increasingly politicized in the use, misappropriation, and commercialisation of their knowledge and biogenetic resources. It is becoming more and more difficult for even the most well-intentioned scientists to stride into indigenous areas and collect plants, animals, folk tales, and photos without having first to convince local leaders that the scholarly efforts will somehow benefit the communities — that the benefits of research results will directly and indirectly lead to strengthening the traditional society. In many parts of the world, indigenous peoples only allow Collaborative Research in which the scientific priorities and agendas are controlled by the communities, or Community Controlled Research in which the communities actually contract scientists to carry out the group's research plan. Control over data has become one of the key battle cries for the indigenous movement, that is now demanding Intellectual Property Rights over information obtained through research and just compensation for economic benefits that eventually may accrue. This paper deals with some of the ethical and practical issues that frame this rapidly evolving debate. 相似文献
105.
Fire regimes in north-eastern Cambodian monsoonal forests, with a 9300-year sediment charcoal record 总被引:3,自引:0,他引:3
Andrew L. Maxwell 《Journal of Biogeography》2004,31(2):225-239
Aim To provide insights concerning changes in fire regime in north‐eastern Cambodia over the course of the Holocene, and discuss implications of these long‐term data for fire management in the present day. Location Southern Ratanakiri Province, north‐eastern Cambodia. The lake sites sampled here are embedded in a mosaic of mostly open, strongly deciduous dipterocarp forest, with patches of riparian, semi‐evergreen and evergreen forests. Methods Background information on the environmental and cultural setting comes from informal and semi‐structured interviews of local villagers to determine present‐day burning patterns and customs. Primary data come from analysis of changes in charcoal concentration within sediments from small, closed basin lakes. Charcoal data are compared with changes in pollen and sediment physical characteristics, and to present‐day local customs, to infer or speculate on changes in human use of fire. Results Interviews with local people reveal two general types of human‐induced fires, one type for swidden cultivation in denser forests, the other type for clearance of ground layer vegetation in more open forests. A 9300‐year sediment record of microscopic charcoal deposition shows strongest fire activity ending by 8000 years ago, and the remainder of the early Holocene reflecting a strong summer monsoon and low fire activity. Beginning c. 5500 years ago, forest disturbance and fire activity increased. A subtle change in the record at c. 3500 years ago and more marked change at c. 2500 years ago suggest that fire frequency, and maybe human control over fire, became more important during that period and continuing up to the present. Main conclusions With this type of empirical data from only one site, it is impossible to make accurate conclusions about long‐term human impacts from burning. However, this record does show that present‐day charcoal input from fire activity is among the lowest for the last 9300 years. Considered together with other changes in the record and with present‐day customs, there is a suggestion that anthropogenic fire is an adaptation to the monsoonal environment, and may be conservative of forest cover in open forest formations. This long‐term perspective on the role of indigenous land‐use customs in landscape evolution should be considered in forest management and biological conservation, as it differs significantly from the traditional rationale for policies of fire suppression in tropical forests. 相似文献
106.
Miki Okuno Rei Kajitani Rie Ryusui Hiroya Morimoto Yukiko Kodama Takehiko Itoh 《DNA research》2016,23(1):67-80
The lager beer yeast Saccharomyces pastorianus is considered an allopolyploid hybrid species between S. cerevisiae and S. eubayanus. Many S. pastorianus strains have been isolated and classified into two groups according to geographical origin, but this classification remains controversial. Hybridization analyses and partial PCR-based sequence data have indicated a separate origin of these two groups, whereas a recent intertranslocation analysis suggested a single origin. To clarify the evolutionary history of this species, we analysed 10 S. pastorianus strains and the S. eubayanus type strain as a likely parent by Illumina next-generation sequencing. In addition to assembling the genomes of five of the strains, we obtained information on interchromosomal translocation, ploidy, and single-nucleotide variants (SNVs). Collectively, these results indicated that the two groups of strains share S. cerevisiae haploid chromosomes. We therefore conclude that both groups of S. pastorianus strains share at least one interspecific hybridization event and originated from a common parental species and that differences in ploidy and SNVs between the groups can be explained by chromosomal deletion or loss of heterozygosity. 相似文献
107.
Guang‐Xin E Tao Zhong Yue‐Hui Ma Hui‐Jiang Gao Jian‐Ning He Nan Liu Yong‐Ju Zhao Jia‐Hua Zhang Yong‐Fu Huang 《Ecology and evolution》2016,6(3):810-817
The domestic sheep (Ovis aries) has been an economically and culturally important farm animal species since its domestication around the world. A wide array of sheep breeds with abundant phenotypic diversity exists including domestication and selection as well as the indigenous breeds may harbor specific features as a result of adaptation to their environment. The objective of this study was to investigate the population structure of indigenous sheep in a large geographic location of the Chinese mainland. Six microsatellites were genotyped for 611 individuals from 14 populations. The mean number of alleles (±SD) ranged from 7.00 ± 3.69 in Gangba sheep to 10.50 ± 4.23 in Tibetan sheep. The observed heterozygote frequency (±SD) within a population ranged from 0.58 ± 0.03 in Gangba sheep to 0.71 ± 0.03 in Zazakh sheep and Minxian black fur sheep. In addition, there was a low pairwise difference among the Minxian black fur sheep, Mongolian sheep, Gansu alpine merino, and Lanzhou fat‐tailed sheep. Bayesian analysis with the program STRUCTURE showed support for 3 clusters, revealing a vague genetic clustering pattern with geographic location. The results of the current study inferred high genetic diversity within these native sheep in the Chinese mainland. 相似文献
108.
Spores and parasporal crystals of a Bacillus thuringiensis var. aizawai H-serotype 7, strain HD137, streptomycin-resistant mutant, were added to normal and autoclaved aliquots of pH 5 soil incubated at 25°C and ?0.10 MPa water availability. Viable B. thuringiensis in soil samples were estimated by dilution-plating on a streptomycin-based medium, and combined spore and crystal insecticidal activity was bioassayed with larvae of Galleria mellonella. Populations of B. thuringiensis in both soil treatments suffered exponential rates of mortality, which were represented by segmented linear regression. Mortality was far greater in natural than autoclaved soil. Potency also fell in both soil treatments. This loss of potency was greater in natural soil, although the rates of potency loss in either soil treatment correlated poorly with the respective mortality rates of the B. thuringiensis populations, as potency losses were not exponential functions. The results suggest that the presence of indigenous microorganisms in natural soil accelerated the rate of mortality and loss of potency of B. thuringiensis. 相似文献
109.
Six local chicken breeds are registered in Hungary and are regarded as Hungarian national treasures: Hungarian White, Yellow and Speckled, and Transylvanian Naked Neck White, Black and Speckled. Three Hungarian academic institutes have maintained these genetic resources for more than 30 years. The Hungarian Yellow, the Hungarian Speckled and the Transylvanian Naked Neck Speckled breeds were kept as duplicates in two separate subpopulations since time of formation of conservation flocks at different institutes. In this study, we investigated genetic diversity of these nine Hungarian chicken populations using 29 microsatellite markers. We assessed degree of polymorphism and relationships within and between Hungarian breeds on the basis of molecular markers, and compared the Hungarian chicken populations with commercial lines and European local breeds. In total, 168 alleles were observed in the nine Hungarian populations. The F ST estimate indicated that about 22% of the total variation originated from variation between the Hungarian breeds. Clustering using structure software showed clear separation between the Hungarian populations. The most frequent solutions were found at K = 5 and K = 6, respectively, classifying the Transylvanian Naked Neck breeds as a separate group of populations. To identify genetic resources unique to Hungary, marker estimated kinships were estimated and a safe set analysis was performed. We show that the contribution of all Hungarian breeds together to the total diversity of a given set of populations was lower when added to the commercial lines than when added to the European set of breeds. 相似文献
110.