Phylogeography of the Australian dunnart Sminthopsis crassicaudata (Marsupialia : Dasyuridae)

2000 ◽  
Vol 48 (5) ◽  
pp. 461 ◽  
Author(s):  
S. J. B. Cooper ◽  
M. Adams ◽  
A. Labrinidis
Keyword(s):  
Conservation Management ◽  
Phylogenetic Analyses ◽  
Allozyme Data ◽  
Evolutionarily Significant Units ◽  
Sminthopsis Crassicaudata ◽  
Control Region Sequences ◽  
Two Populations ◽  
Maternal Gene ◽  
Mtdna Haplotype

Analyses of mitochondrial DNA (mtDNA) and allozymes are used to investigate the population genetic structure, phylogeography and systematics of the fat-tailed dunnart, Sminthopsis crassicaudata. Phylogenetic analyses of control region sequences reveal the presence of two major mtDNA haplotype clades. A survey of the distribution of the two clades using diagnostic restriction endonucleases shows that one clade is restricted to southeast Australia whereas the second clade occupies the remaining central to western range of S. crassicaudata. Allozyme electrophoresis also shows concordant patterns of population structure, with significant differences in allele frequency at three loci between populations in the southeast and northwest. Together, the mtDNA and allozyme data provide evidence that S. crassicaudata consists of two Evolutionarily Significant Units (ESUs). The distribution of each ESU is not concordant with the distribution of the subspecies of S. crassicaudata, and we propose that the current subspecies classification neither reflects the major genetic subdivisions present within S. crassicaudata nor would be appropriate for any future conservation management. The level of divergence between mtDNA clades (3.4%) is indicative of cladogenesis in the Pleistocene and reflects a long-term barrier to maternal gene flow between these two populations. One potential historical barrier was Lake Bungunnia, which persisted in the Murray basin over much of the Pleistocene.

Conservation genetics of the wood turtle (Glyptemys insculpta) in Quebec, Canada

2005 ◽  
Vol 83 (6) ◽  
pp. 765-772 ◽  
Author(s):  
Nathalie Tessier ◽  
Sébastien Rioux Paquette ◽  
François-Joseph Lapointe
Keyword(s):  
Phylogenetic Analyses ◽  
Population Declines ◽  
Conservation Units ◽  
The North ◽  
Glyptemys Insculpta ◽  
South Shore ◽  
Two Populations ◽  
St Lawrence River ◽  
Wood Turtle

Throughout its range, the long-term persistence of the wood turtle (Glyptemys insculpta Le Conte, 1830) is jeopardized by habitat perturbations and commercial collection. The main objective of this study was to acquire knowledge on the genetic structure of wood turtle populations within Quebec, where the species reaches the northernmost limit of its range, to identify proper conservation units. The six known populations in Quebec were genetically characterized using five microsatellite loci. Genetic analyses revealed high variability among all populations (HO ranging from 0.561 to 0.886), suggesting that past population declines have not yet affected their genetic diversity. Since populations are located on both shores of the St. Lawrence River, two colonization hypotheses were tested to determine whether the River acted as a dispersal route or as a barrier. Results of AMOVA tests, phylogenetic analyses, and assignment tests demonstrated the clear distinction between populations from both shores, and three genetically different units were identified: the two populations on the north shore and a single homogenous group on the south shore.

scholarly journals Long-term changes in the plant ecology of an African savanna landscape and the implications for ecosystem theory and conservation management

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
David Western ◽  
Victor N. Mose ◽  
David Maitumo ◽  
Caroline Mburu
Keyword(s):  
Human Impact ◽  
National Parks ◽  
Conservation Management ◽  
Plant Ecology ◽  
Ecological Resilience ◽  
Pasture Production ◽  
Ecosystem Theory ◽  
The Impact

Abstract Background Studies of the African savannas have used national parks to test ecological theories of natural ecosystems, including equilibrium, non-equilibrium, complex adaptive systems, and the role of top-down and bottom-up physical and biotic forces. Most such studies have excluded the impact of pastoralists in shaping grassland ecosystems and, over the last half century, the growing human impact on the world’s rangelands. The mounting human impact calls for selecting indicators and integrated monitoring methods able to track ecosystem changes and the role of natural and human agencies. Our study draws on five decades of monitoring the Amboseli landscape in southern Kenya to document the declining role of natural agencies in shaping plant ecology with rising human impact. Results We show that plant diversity and productivity have declined, biomass turnover has increased in response to a downsizing of mean plant size, and that ecological resilience has declined with the rising probability of extreme shortfalls in pasture production. The signature of rainfall and physical agencies in driving ecosystem properties has decreased sharply with growing human impact. We compare the Amboseli findings to the long-term studies of Kruger and Serengeti national parks to show that the human influence, whether by design or default, is increasingly shaping the ecology of savanna ecosystems. We look at the findings in the larger perspective of human impact on African grasslands and the world rangelands, in general, and discuss the implications for ecosystem theory and conservation policy and management. Conclusions The Amboseli study shows the value of using long-term integrated ecological monitoring to track the spatial and temporal changes in the species composition, structure, and function of rangeland ecosystems and the role of natural and human agencies in the process of change. The study echoes the widespread changes underway across African savannas and world’s rangelands, concluding that some level of ecosystem management is needed to prevent land degradation and the erosion of ecological function, services, and resilience. Despite the weak application of ecological theory to conservation management, a plant trait-based approach is shown to be useful in explaining the macroecological changes underway.

scholarly journals Transcriptome and chromatin landscape of iNKT cells are shaped by subset differentiation and antigen exposure

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Mallory Paynich Murray ◽  
Isaac Engel ◽  
Grégory Seumois ◽  
Sara Herrera-De la Mata ◽  
Sandy Lucette Rosales ◽  
...  
Keyword(s):  
T Cells ◽  
Inkt Cells ◽  
Phenotypic Analysis ◽  
Follicular Helper ◽  
Transcriptional Changes ◽  
Innate Lymphocytes ◽  
Killer T Cells ◽  
Invariant Natural Killer ◽  
Two Populations

AbstractInvariant natural killer T cells (iNKT cells) differentiate into thymic and peripheral NKT1, NKT2 and NKT17 subsets. Here we use RNA-seq and ATAC-seq analyses and show iNKT subsets are similar, regardless of tissue location. Lung iNKT cell subsets possess the most distinct location-specific features, shared with other innate lymphocytes in the lung, possibly consistent with increased activation. Following antigenic stimulation, iNKT cells undergo chromatin and transcriptional changes delineating two populations: one similar to follicular helper T cells and the other NK or effector like. Phenotypic analysis indicates these changes are observed long-term, suggesting that iNKT cells gene programs are not fixed, but they are capable of chromatin remodeling after antigen to give rise to additional subsets.

scholarly journals A floristic description of the Afromontane fynbos communities on Platberg, Eastern Free State, South Africa

Koedoe ◽  
2008 ◽  
Vol 50 (1) ◽  
Author(s):  
Robert F. Brand ◽  
Pieter J. Du Preez ◽  
Leslie R. Brown
Keyword(s):  
Natural Resources ◽  
Plant Communities ◽  
Conservation Management ◽  
Alien Invasive Species ◽  
Ecological Processes ◽  
The North ◽  
Shrub Community ◽  
Management Plans ◽  
Twinspan Classification

Within the Platberg area and the wider Drakensberg region, the shrinking natural resources and the threat posed to biodiversity are of concern to conservation management and require an understanding of long-term ecological processes. The vegetation of Platberg was investigated as part of an ecological survey to establish Afromontane floristic links to the Drakensberg as well as for the management of natural resources. From a TWINSPAN classification, refined by the Braun-Blanquet method, four main plant communities were identified, which were subdivided into fynbos, wetland, a woody/shrub community and grassland. A classification and description of the fynbos are presented in this article.The analysis showed the fynbos divided into two communities comprising four sub-communities and seven variants. The fynbos community had an average of 28.34 species per relevé, ranging from 14 to 54 species per sample plot. Twenty-four endemic or near-endemic Drakensberg Alpine Centre (DAC) species and 22 exotic (alien-invasive) species were recorded. Numerous floristic links with the DAC, Cape flora fynbos and grassland bioregions to the north and west were also found. The description of the fynbos plant communities can serve as a basis for the formulation of management plans for the area.

scholarly journals Phylogenetic Analyses of HBV Pre-S/S Genes in Mother-Child Pairs with Long-Term Infection by Presumed Vertical Transmission

2014 ◽  
Vol 29 (4) ◽  
pp. 564 ◽  
Author(s):  
Hyoung Su Kim ◽  
Bo Youn Choi ◽  
Hyeok Soo Choi ◽  
Woon Geon Shin ◽  
Kyung Ho Kim ◽  
...  
Keyword(s):  
Vertical Transmission ◽  
Phylogenetic Analyses ◽  
S Genes

scholarly journals Unravelling causality from correlations: revealing the impacts of endemic ectoparasites on a protected species (tuatara)

Parasitology ◽  
2009 ◽  
Vol 137 (2) ◽  
pp. 275-286 ◽  
Author(s):  
STEPHANIE S. GODFREY ◽  
JENNIFER A. MOORE ◽  
NICOLA J. NELSON ◽  
C. MICHAEL BULL
Keyword(s):  
Body Condition ◽  
Conservation Management ◽  
Essential Element ◽  
The Body ◽  
Protected Species ◽  
Manipulative Experiments ◽  
Sphenodon Punctatus ◽  
Correlative Studies ◽  
Experimental Structure

SUMMARYUnderstanding the impacts of endemic parasites on protected hosts is an essential element of conservation management. However, where manipulative experiments are unethical, causality cannot be inferred from observational correlative studies. Instead, we used an experimental structure to explore temporal associations between body condition of a protected reptile, the tuatara (Sphenodon punctatus) and infestation with ectoparasites (ticks and mites). We surveyed tuatara in a mark-recapture study on Stephens Island (New Zealand), which encompassed the pre-peak, peak and post-peak infestation periods for each ectoparasite. Tick loads during the peak infestation period were negatively related to body condition of tuatara. Body condition before the peak was not related to subsequent infestation rates; however, tick loads in the peak were negatively related to subsequent changes in body condition. Mite loads during the peak infestation period were not correlated with body condition of tuatara. Body condition before the peak had no effect on subsequent mite infestation rates, but mite loads of small males during the peak were negatively related to subsequent changes in body condition. Our results suggest that both ectoparasites reduce the body condition of tuatara, which has implications for the long-term conservation management of this host and its parasites.

Molecular and morphological characterisation of Cryptaphelenchus baujardi n. sp. (Nematoda: Ektaphelenchinae), a new species based on two populations from Iran

Nematology ◽  
2019 ◽  
Vol 21 (1) ◽  
pp. 45-56 ◽  
Author(s):  
Farzad Aliramaji ◽  
Esmaeil Miraeiz ◽  
Ebrahim Pourjam ◽  
Ramin Heydari
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Lsu Rdna ◽  
New Taxon ◽  
Male Body ◽  
Northern Iran ◽  
Lateral Field ◽  
Rdna Sequences ◽  
Strong Resemblance ◽  
Two Populations

Summary Cryptaphelenchus baujardi n. sp. is described and illustrated based on two populations from Golestan province, northern Iran. The new species is characterised by female and male body length of 224 (190-261) and 215 (195-229) μm, respectively, offset cephalic region with a shallow constriction, delicate stylet 6.6 (6.0-7.0) μm long, four incisures in the lateral field, presence of a rudimentary post-uterine sac in the female gonoduct, elongate-conoid female tail ending in an acute to finely rounded terminus, male tail conical, male with seven caudal papillae and delicate spicules. The new species shows a strong resemblance to C. varicaudatus and C. iranicus, but has a sclerotised mass near the tip of the spicule and an indistinct spermatheca. Phylogenetic analyses based on both partial SSU and LSU rDNA sequences confirm its status as a new taxon.

scholarly journals Risk of Symptomatic Infection after Non-Primary Congenital Cytomegalovirus Infection

2020 ◽  
Vol 8 (5) ◽  
pp. 786
Author(s):  
Alessandra Coscia ◽  
Agata Leone ◽  
Carlotta Rubino ◽  
Ganna Galitska ◽  
Matteo Biolatti ◽  
...  
Keyword(s):  
Primary Infection ◽  
Clinical Laboratory ◽  
Congenital Infection ◽  
Symptomatic Infection ◽  
Symptomatic Disease ◽  
Significant Difference ◽  
Neonatal Care Unit ◽  
Two Populations

Cytomegalovirus (CMV) is the leading cause of congenital infection. Its occurrence is phenotypically heterogeneous. The type of maternal infection, primary or non-primary, is an important factor related to the symptomatic disease, the primary infection was long considered the only cause of severe neonatal disease. We aimed to analyze the association of primary and non-primary infection with pathological outcomes in infants and with long-term sequelae at follow-up. This was a monocentric retrospective observational study on a population of 91 infants diagnosed with a CMV infection at the Neonatal Care Unit of Neonatology at the Sant’Anna Hospital of Turin during the period of June 2005 to December 2018. Infants underwent clinical, laboratory, and neuroradiological evaluations at birth. Subsequently, the patients were monitored in an auxological, neurodevelopment, and audiological follow-up. Regarding primary vs. non-primary infection, we found a higher percentage of incidence of symptomatic and neurological localized infection, as well as long-term sequelae in the latter. However, no significant difference between the two populations was found. We underline the possibility of re-infection in previously immunized mothers (non-primary infection) with unfavorable neonatal and long-term outcomes.

Electrophoretic characterization of Solomon Islands populations of Nyctimene and Rousettus (Chiroptera: Pteropodidae).

2003 ◽  
Vol 25 (1) ◽  
pp. 41 ◽  
Author(s):  
JM Macaranas ◽  
D Colgan ◽  
S Ingleby
Keyword(s):  
Papua New Guinea ◽  
Solomon Islands ◽  
Taxonomic Status ◽  
Genetic Distances ◽  
Allozyme Data ◽  
Separate Species ◽  
Bismarck Archipelago ◽  
A Minor ◽  
Two Populations

The taxonomic status of fruitbats belonging to the genera Nyctimene and Rousettus from the Solomon Islands was investigated using allozyme electrophoresis. Two populations from the Bismarck Archipelago (Papua New Guinea) were included as reference profiles. The allozyme data at 23 loci assigned all specimens into either Nyctimene albiventer or Nyctimene major. The N. albiventer specimens comprised two subspecies, N. a. papuanus from the Bismarck Archipelago and N. a. bougainville from the Solomon Islands. No support was evident for bougainville being a separate species, and indeed the data suggest that N. a. bougainville encompasses the previously described species N. malaita and subspecies N. a. minor. Genetic distances between populations of R. amplexicaudatus from the Bismarck Archipelago and the Solomon Islands were generally low, supporting recent morphological assessments that the subspecies hedigeri, from the majority of the Solomon Islands, should be considered synonymous with subspecies brachyotis. An individual from Choiseul (Solomon Islands) with a distinctive allozyme profile is the only evidence of taxonomic complexity in R. amplexicaudatus.

scholarly journals The decline and conservation management of the threatened endemic palms of the Mascarene Islands

Oryx ◽  
2002 ◽  
Vol 36 (1) ◽  
pp. 56-65 ◽  
Author(s):  
Mike Maunder ◽  
Wayne Page ◽  
John Mauremootoo ◽  
Richard Payendee ◽  
Yousoof Mungroo ◽  
...  
Keyword(s):  
Large Scale ◽  
Conservation Management ◽  
Conservation Status ◽  
Iucn Red List ◽  
Ex Situ ◽  
Population Fragmentation ◽  
Wild Populations ◽  
Mascarene Islands

Abstract The conservation status of the five genera and 11 species of palm endemic to the Mascarene Islands (Mauritius, La Réunion and Rodriques) are reviewed. All species are threatened with extinction; nine taxa are classified as Critically Endangered and four as Endangered on the 2000 IUCN Red List. Two taxa survive as single wild specimens (Hyophorbe amaricaulis and Dictyosperma album var. conjugatum); an additional seven taxa have wild populations of 100 or fewer. Although the historical phase of large-scale forest clearance has passed, the remaining palm populations in the Mascarenes are under threat from the effects of population fragmentation, invasive plants and animals, and high levels of seed predation that prevent natural regeneration. The advantages of in situ management for the recovery of these palm populations are discussed. Without a long-term conservation programme, utilising both in situ and ex situ management, extinction of wild populations will occur.

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