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41.
Klára J. Petrželková Hideo Hasegawa Chris C. Appleton Michael A. Huffman Colleen E. Archer Liza R. Moscovice Mwanahamissi Issa Mapua Jatinder Singh Taranjit Kaur 《American journal of primatology》2010,72(4):307-316
The release of any species into a novel environment can evoke transmission of parasites that do not normally parasitize the host as well as potentially introducing new parasites into the environment. Species introductions potentially incur such risks, yet little is currently known about the parasite fauna of introduced primate species over the long term. We describe the results of long‐term monitoring of the intestinal parasite fauna of an unprovisioned, reproducing population of chimpanzees introduced 40 years earlier (1966–1969) onto Rubondo Island in Lake Victoria, Tanzania, a non‐native habitat for chimpanzees. Two parasitological surveys (March 1997–October 1998 and October 2002–December 2005) identified Entamoeba spp. including E. coli, Iodamoeba buetschlii, Troglodytella abrassarti, Chilomastix mesnili, Trichuris sp., Anatrichosoma sp., Strongyloides spp., Strongylida fam. gen. sp., Enterobius anthropopitheci, Subulura sp., Ascarididae gen. sp., and Protospirura muricola. The parasite fauna of the Rubondo chimpanzees is similar to wild chimpanzees living in their natural habitats, but Rubondo chimpanzees have a lower prevalence of strongylids (9%, 3.8%) and a higher prevalence of E. anthropopitheci (8.6%, 17.9%) than reported elsewhere. Species prevalence was similar between our two surveys, with the exception of Strongyloides spp. being higher in the first survey. None of these species are considered to pose a serious health risk to chimpanzees, but continued monitoring of the population and surveys of the parasitic fauna of the two coinhabitant primate species and other animals, natural reservoir hosts of some of the same parasites, is important to better understand the dynamics of host–parasite ecology and potential long‐term implications for chimpanzees introduced into a new habitat. Am. J. Primatol. 72:307–316, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
42.
花楸属(Sorbus L.)植物冠形多态、花色秀美、果实缤纷、四季叶色各异,具有很高的园艺观赏价值,但因属下种间杂交、多倍化和无融合生殖的存在,所以花楸属也是分类学上比较困难的一个类群。该研究通过细致整理和分析国家标本资源库和全球数字化植物标本数据库中花楸属植物标本信息,了解中国花楸属物种采集位置和野生种质资源的分布中心,构建中国花楸属植物标本数据库,为全国第一次林草种质资源的普查与收集提供参考;在明晰花楸属植物资源分布位置和生境的基础上,发现中国花楸属植物资源居世界之首且花楸属物种多分布在高海拔区域,尤其是在中国西南部的山区,分布有一半以上的中国花楸属物种,在该区域花楸属物种多种倍性并存、杂交频繁发生。然而,这是否为该属植物物种多样性丰富的关键因素,把高海拔分布的花楸属物种引种到低海拔区域能否适应以及如何适应低海拔的夏季高温尚不清楚。基于此,作者就自己的专业领域进一步检索了花楸属植物在形态分类与系统发育、适应性进化和保护遗传学、植物资源利用等方面的研究现状,梳理出花楸属植物目前研究尚未解决的问题,并进一步指出未来研究需重点关注的方向。建议未来的研究重点关注以下问题:(1)在坚实的系统... 相似文献
43.
M Thomasset T R Hodkinson G Restoux N Frascaria-Lacoste G C Douglas J F Fernández-Manjarrés 《Heredity》2014,112(6):596-606
The risks of gene flow between interfertile native and introduced plant populations are
greatest when there is no spatial isolation of pollen clouds and phenological patterns
overlap completely. Moreover, invasion probabilities are further increased if introduced
populations are capable of producing seeds by selfing. Here we investigated the mating
system and patterns of pollen-mediated gene flow among populations of native ash
(Fraxinus excelsior) and mixed plantations of non-native ash (F.
angustifolia and F. excelsior) as well as hybrid ash (F.
excelsior × F. angustifolia) in Ireland. We analysed the flowering
phenology of the mother trees and genotyped with six microsatellite loci in progeny arrays
from 132 native and plantation trees (1493 seeds) and 444 potential parents. Paternity
analyses suggested that plantation and native trees were pollinated by both native and
introduced trees. No signs of significant selfing in the introduced trees were observed
and no evidence of higher male reproductive success was found for introduced trees
compared with native ones either. A small but significant genetic structure was found
(φft=0.05) and did not correspond to an isolation-by-distance
pattern. However, we observed a significant temporal genetic structure related to the
different phenological groups, especially with early and late flowering native trees; each
phenological group was pollinated with distinctive pollen sources. Implications of these
results are discussed in relation to the conservation and invasiveness of ash and the
spread of resistance genes against pathogens such as the fungus Chalara fraxinea
that is destroying common ash forests in Europe. 相似文献
44.
45.
Aim This paper evaluates global collection records, evidence of anthropogenic transport methods, and experimental and distributional data relative to temperature requirements to understand the historical and potential dispersal of a well‐known genus of estuarine crab. Location The records analysed are from temperate and tropical coastal ocean areas. Methods The study is based primarily on literature analysis and examination of museum specimens. Results The human‐mediated successful global dispersal of the European shore crabs Carcinus maenas (Linnaeus, 1758) and C. aestuarii (Nardo, 1847) occurred in three major episodes: around 1800, in the 1850s–70s, and in the 1980s–90s. The nineteenth century introductions occurred through transport by ships (probably in hull fouling or in solid ballast), while the introductions in the 1980s could have occurred through a greater variety of dispersal mechanisms (ships’ hull fouling and seawater system fouling; fouling on semisubmersible drilling platforms; ballast water; transport with fisheries products intended for food or bait; scientific research; releases from aquaria maintained for educational or scientific purposes; or intentional non‐governmental releases for human food production). These introductions have resulted in Carcinus’ establishment in five temperate regions outside of its native Europe in Atlantic North America, Australia, South Africa, Japan and Pacific North America, while releases into tropical regions have not established populations. C. maenas’ range in both its native and introduced regions appears to be regulated by similar temperature parameters, enabling an assessment of its potential distribution. Main conclusions The second episode of Carcinus’ global dispersal, the period from the 1850s to 1870s, may be part of a broader surge of world‐wide invasions caused by an increase in shipping. 相似文献
46.
The intentional introduction of red king crab, Paralithodes camtschatica (Tilesius, 1815) in the Barents Sea represent one of a few successful cases and one that now supports a commercial fishery.
Introductions of alien species into new environments are often associated with genetic bottlenecks, which cause a reduction
in the genetic variation, and this could be important for the spreading potential of the species in the Atlantic Ocean. Red
king crab samples collected in the Varangerfjord located on the Barents Sea (northern Norway) were compared with reference
crab samples collected from the Bering Sea and Kamchatka regions in the Pacific Ocean. All samples were screened for eleven
microsatellite loci, based on the development of species-specific primers. The observed number of alleles per locus was similar,
and no reduction in genetic variation, including gene diversity and allelic richness, was detected between the Varangerfjord
sample and the reference sample from Okhotsk Sea near Kamchatka, indicating no genetic bottlenecking at least for the microsatellite
loci investigated. The same results were found in comparison with the sample from Bering Sea. The level of genetic differentiation
among the samples, measured as overall F
ST
across all loci, was relatively low (0.0238) with a range of 0.0035–0.1000 for the various loci investigated. The largest
pairwise F
ST
values were found between the Bering Sea and Varangerfjord/Barents Sea samples, with a value of 0.0194 across all loci tested.
The lowest value (0.0101) was found between the Varangerfjord and Kamchatka samples. Genetic differentiation based on exact
tests on allele frequencies revealed highly significant differences between all pairwise comparisons. The high level of genetic
variation found in the Varangerfjord/Barents Sea sample could be of significance with respect to further spreading of the
species to other regions in the North Atlantic Ocean. 相似文献
47.
Low parasite loads accompany the invading population of the bumblebee, Bombus terrestris in Tasmania
In its native Europe, the bumblebee, Bombus terrestris (L.) has co-evolved with a large array of parasites whose numbers are negatively linked to the genetic diversity of the colony.
In Tasmania B. terrestris was first detected in 1992 and has since spread over much of the state. In order to understand the bee’s invasive success
and as part of a wider study into the genetic diversity of bumblebees across Tasmania, we screened bees for co-invasions of
ectoparasitic and endoparasitic mites, nematodes and micro-organisms, and searched their nests for brood parasites. The only
bee parasite detected was the relatively benign acarid mite Kuzinia laevis (Dujardin) whose numbers per bee did not vary according to region. Nests supported no brood parasites, but did contain the
pollen-feeding life stages of K. laevis. Upon summer-autumn collected drones and queens, mites were present on over 80% of bees, averaged ca. 350–400 per bee and
were more abundant on younger bees. Nest searching spring queens had similar mite numbers to those collected in summer-autumn
but mite numbers dropped significantly once spring queens began foraging for pollen. The average number of mites per queen
bee was over 30 fold greater than that reported in Europe. Mite incidence and mite numbers were significantly lower on worker
bees than drones or queens, being present on just 51% of bees and averaging 38 mites per bee. Our reported incidence of worker
bee parasitism by this mite is 5–50 times higher than reported in Europe. That only one parasite species co-invaded Tasmania
supports the notion that a small number of queens founded the Tasmanian population. However, it is clearly evident that both
the bee in the absence of parasites, and the mite have been extraordinarily successful invaders.
Received 12 April 2006; revised 10 November 2006; accepted 15 November 2006. 相似文献
48.
Testing the role of genetic factors across multiple independent invasions of the shrub Scotch broom (Cytisus scoparius) 总被引:1,自引:1,他引:0
Knowledge of the introduction history of invasive plants informs on theories of invasiveness and assists in the invasives management. For the highly successful invasive shrub Scotch broom, Cytisus scoparius, we analysed a combination of nuclear and chloroplast microsatellites for eight native source regions and eight independent invasion events in four countries across three continents. We found that two exotic Australian populations came from different sources, one of which was derived from multiple native populations, as was an invasive sample from California. An invasive population from New Zealand appeared to be predominantly sourced from a single population, either from the native or exotic ranges. Four invasive populations from Chile were genetically differentiated from the native range samples analysed here and so their source of introduction could not be confirmed, but high levels of differentiation between the Chilean populations suggested a combination of different sources. This extensive global data set of replicated introductions also enabled tests of key theories of invasiveness in relation to genetic diversity. We conclude that invasive populations have similar levels of high genetic diversity to native ranges; levels of admixture may vary across invasive populations so admixture does not appear to have been an essential requirement for invasion; invasive and native populations exhibit similar level of genetic structure indicating similar gene flow dynamics for both types of populations. High levels of diversity and multiple source populations for invasive populations observed here discount founder effects or drift as likely explanations for previously observed seed size differences between ranges. The high levels of genetic diversity, differential and source admixture identified for most exotic populations are likely to limit the ability to source biocontrol agents from the native region of origin of invasive populations. 相似文献
49.
Phillip Cassey Julie L. Lockwood Tim M. Blackburn Julian D. Olden 《Diversity & distributions》2007,13(4):458-466
It is widely documented that human activities have elevated the extirpation of natural populations as well as the successful introduction to new areas of non-native species. These dual processes of introduction and extirpation can change the similarity of communities, but the direction and magnitude these changes take are likely to depend on the manner in which introductions and extirpations occur, the spatial scale at which the changes are measured, and the initial similarity of the communities before the human-induced drivers occurred. Here, we explore patterns of extirpation and introduction and their influence on the similarity of global oceanic island bird assemblages from four different Oceans (Atlantic, Caribbean, Indian, Pacific). We show that different historical patterns of introduction and extirpation have produced varying trends in compositional similarity both between islands within archipelagos and between islands across different archipelagos within the same ocean. Patterns of bird assemblage convergence (i.e. taxonomic homogenization) or divergence (i.e. taxonomic differentiation) among islands depended on the scale of examination, the evolutionary associations among species of the region, and the cultural history of human colonization. These factors are all likely to be leading to a series of multiple interacting processes that are shaping the complex compositional changes observed among global island bird faunas over time. 相似文献
50.
Recognition and Response to Native and Novel Predators in the Largespring mosquitofish,Gambusia geiseri 下载免费PDF全文
Chelsea A. Blake Laura Alberici da Barbiano Jessica E. Guenther Caitlin R. Gabor 《Ethology : formerly Zeitschrift fur Tierpsychologie》2015,121(3):227-235
The introduction of predator species into new habitats is an increasingly common consequence of human activities, and the persistence of native prey species depends upon their response to these novel predators. In this study, we examined whether the Largespring mosquitofish, Gambusia geiseri exhibited antipredator behavior and/or an elevation of circulating stress hormones (cortisol) to visual and chemical cues from a native predator, a novel predator, or a non‐predatory control fish. Prey showed the most pronounced antipredator response to the native predator treatment, by moving away from the stimulus, while the prey showed no significant changes in their vertical or horizontal position in response to the novel or non‐predator treatments. We also found no significant difference in water‐borne cortisol release rates following any of the treatments. Our results suggest the prey did not recognize and exhibit antipredator behavior to the novel predator, and we infer that this predator species could be detrimental if it expands into the range of this prey species. Further, our study demonstrates prey may not respond to an invasive predator that is phylogenetically, behaviorally, and morphologically dissimilar from the prey species' native predators. 相似文献