scholarly journals Genetic diversity among populations of Antarctic springtails (Collembola) within the Mackay Glacier ecotone

Genome ◽  
2016 ◽  
Vol 59 (9) ◽  
pp. 762-770 ◽  
Author(s):  
Clare R. Beet ◽  
Ian D. Hogg ◽  
Gemma E. Collins ◽  
Don A. Cowan ◽  
Diana H. Wall ◽  
...  
Keyword(s):  
Climate Changes ◽  
Ross Sea ◽  
Sequence Divergence ◽  
Running Waters ◽  
The North ◽  
Victoria Land ◽  
The Reformation ◽  
Springtail Species ◽  
Biogeographic Regions ◽  
Coi Sequences

Climate changes are likely to have major influences on the distribution and abundance of Antarctic terrestrial biota. To assess arthropod distribution and diversity within the Ross Sea region, we examined mitochondrial DNA (COI) sequences for three currently recognized species of springtail (Collembola) collected from sites in the vicinity, and to the north of, the Mackay Glacier (77°S). This area acts as a transition between two biogeographic regions (northern and southern Victoria Land). We found populations of highly divergent individuals (5%–11.3% intraspecific sequence divergence) for each of the three putative springtail species, suggesting the possibility of cryptic diversity. Based on molecular clock estimates, these divergent lineages are likely to have been isolated for 3–5 million years. It was during this time that the Western Antarctic Ice Sheet (WAIS) was likely to have completely collapsed, potentially facilitating springtail dispersal via rafting on running waters and open seaways. The reformation of the WAIS would have isolated newly established populations, with subsequent dispersal restricted by glaciers and ice-covered areas. Given the currently limited distributions for these genetically divergent populations, any future changes in species’ distributions can be easily tracked through the DNA barcoding of springtails from within the Mackay Glacier ecotone.

scholarly journals Technical procedures for aeromagnetic surveys in Antarctica during the Italian expeditions (1988-1992)

1994 ◽  
Vol 37 (5 Sup.) ◽  
Author(s):  
E. Bozzo ◽  
A. Colla ◽  
G. Caneva ◽  
A. Meloni ◽  
A. Caramelli ◽  
...  
Keyword(s):  
Ross Sea ◽  
Base Stations ◽  
Aeromagnetic Survey ◽  
The North ◽  
Terra Nova Bay ◽  
Victoria Land ◽  
Range Type ◽  
Line Spacing ◽  
Tie Lines ◽  
Shelf Region

For most of Antarctica, the geophysical data now available are those of aeromagnetic surveys performed there from 1950 to 1960. Until 1984, the inaccurate positioning and insufficient monitoring of geomagnetic time variations allowed the investigation of the geomagnetic residual field only along profiles. The Ganovex IV aeromagnetic survey, performed by BGR-USGS over the Ross Sea and the Northern Victoria Land, and the geophysical investigations of BAS on the Southern Antarctic peninsula and the Ronne ice shelf region corresponds to the recent advancement of these techniques in Antarctica. The first experiments of aeromagnetic measurements, during the Italian expeditions in Antarctica were made during the 1988-1989 field season. Some geomagnetic helicopter borne profiles were accomplished with a Proton Precession Magnetometer (PPM) in the Terra Nova Bay-Gerlache Inlet area. In the 1989-1990 ItaliAntartide expedition some profiles were flown over the suture between the Wilson and Bower terranes, in Northern Victoria Land. During the 1991-1992 expedition, in cooperation with researchers of BGR (Bundesanstalt fur Geowissenschaften und Rohstoffe) of Hannover, the GITARA I (German ITalian Aeromagnetic Rescarch Antarctica) program, as part of the LIRA (Litospheric Investigation in the Ross Sea Area) project, was carried out. The investigated area lies between the latitudes 74°18' S and 75°18' S and the longitudes 160°30' E and 164°30'E and it corresponds to a portion of the North Victoria Land, located between the Eisenhower Range and the, DrygaIski Ice Tongue. The survey was made with a Cesium vapour magnetometer. The positioning system was of the “Range-Range” type, it consisted of three transmitters (beacons), installed inside the investigated area and located with GPS measurements. The line spacing was 4.4 km, with tie lines every 22 km. The survey covered an area of 6500 km2 . Four PPM base stations for the determination of the time variation corrections were installed. The aeromagnetic anomalies wilI allow the comparison with the ground geomagnetic surveys performed during the previous Antarctic expeditions, also in connection with the aeromagnetic maps of Ganovex IV, located at the northern and eastern boundaries of the GITARA area.

scholarly journals Latitudinal distribution and mitochondrial DNA (COI) variability of Stereotydeus spp. (Acari: Prostigmata) in Victoria Land and the central Transantarctic Mountains

2010 ◽  
Vol 22 (6) ◽  
pp. 749-756 ◽  
Author(s):  
Nicholas J. Demetras ◽  
Ian D. Hogg ◽  
Jonathan C. Banks ◽  
Byron J. Adams
Keyword(s):  
Mitochondrial Dna ◽  
Phylogenetic Trees ◽  
Bootstrap Support ◽  
Latitudinal Distribution ◽  
Monophyletic Clade ◽  
The North ◽  
Victoria Land ◽  
High Bootstrap ◽  
Transantarctic Mountains ◽  
Coi Sequences

AbstractWe examined mitochondrial DNA (COI) variability and distribution of Stereotydeus spp. in Victoria Land and the Transantarctic Mountains, and constructed Neighbour Joining (NJ) and Maximum Likelihood (ML) phylogenetic trees using all publicly available COI sequences for the three Stereotydeus species present (S. belli, S. mollis and S. shoupi). We also included new COI sequences from Miers, Marshall and Garwood valleys in southern Victoria Land (78°S), as well as from the Darwin (79°S) and Beardmore Glacier (83°S) regions. Both NJ and ML methods produced trees which were similar in topology differing only in the placement of the single available S. belli sequence from Cape Hallett (72°S) and a S. mollis haplotype from Miers Valley. Pairwise sequence divergences among species ranged from 9.5–18.1%. NJ and ML grouped S. shoupi from the Beardmore Glacier region as sister to those from the Darwin with pairwise divergences of 8%. These individuals formed a monophyletic clade with high bootstrap support basal to S. mollis and S. belli. Based on these new data, we suggest that the distributional range of S. shoupi extends northward to Darwin Glacier and that a barrier to dispersal for Stereotydeus, and possibly other arthropods, exists immediately to the north of this area.

Two unpublished accounts of the British Antarctic Expedition, 1839–43

Polar Record ◽  
1961 ◽  
Vol 10 (69) ◽  
pp. 587-604
Keyword(s):  
Ross Sea ◽  
Terrestrial Magnetism ◽  
The North ◽  
Prince Edward Islands ◽  
Victoria Land ◽  
Antarctic Expedition ◽  
North Magnetic Pole ◽  
Antarctic Continent ◽  
James Ross Island ◽  
Set Up

[The British Antarctic Expedition, 1839–43, consisted of two Naval vessels, H.M.S. Erebus and Terror, with Sir James Clark Ross as leader and Captain F. R. M. Crozier as second-in-command. The objects of the expedition were mainly concerned with terrestrial magnetism, a subject of particular interest to Ross who had discovered the North Magnetic Pole in 1831. The expedition circumnavigated the Antarctic continent and made a number of important geographical discoveries. It twice penetrated the pack ice.of the Ross Sea; it discovered, and roughly charted, 500 miles of new coastline in Victoria Land; it discovered Ross Island and the Ross Ice Front, also the James Ross Island group; it visited Prince Edward Islands, les Crozet and les Kerguelen; and it sighted Joinville Island and the Balleny Islands. Observations of terrestrial magnetism were made from stations, either permanent or temporary, set up during the voyage.

scholarly journals Victoria Lower Glacier and Ross Sea Glaciation, Dry Valleys Area, South Victoria Land, Antarctica

1987 ◽  
Vol 33 (115) ◽  
pp. 293-299 ◽  
Author(s):  
T.J.H. Chinn
Keyword(s):  
Shear Zone ◽  
Ross Sea ◽  
Complex Structure ◽  
Radiocarbon Date ◽  
Dry Valleys ◽  
Radiocarbon Age ◽  
The North ◽  
Victoria Land ◽  
Radio Echo Sounding ◽  
Echo Sounding

AbstractVictoria Lower Glacier is a complex structure of ice from two distinct sources (Schultz Glacier to the north and a localnévéof Victoria Lower Glacier) that join at a broad median shear zone. Evidence from the margins suggest that both are currently retreating. Algae in a block of frozen stratified sediment from within the ice of the terminal margin has a radiocarbon age of 20 200 ± 2400 year BP (NZ 6531 A), indicating that the glacier has advanced since that time. Superposition of ice levels of Ross Sea I glaciation on a radio echo–sounding profile of bedrock beneath the glacier indicates that it is unlikely that Ross Sea I ice entered the valley. The radiocarbon date supports this finding.

scholarly journals Victoria Lower Glacier and Ross Sea Glaciation, Dry Valleys Area, South Victoria Land, Antarctica

1987 ◽  
Vol 33 (115) ◽  
pp. 293-299
Author(s):  
T.J.H. Chinn
Keyword(s):  
Shear Zone ◽  
Ross Sea ◽  
Complex Structure ◽  
Radiocarbon Date ◽  
Dry Valleys ◽  
Radiocarbon Age ◽  
The North ◽  
Victoria Land ◽  
Radio Echo Sounding ◽  
Echo Sounding

AbstractVictoria Lower Glacier is a complex structure of ice from two distinct sources (Schultz Glacier to the north and a local névé of Victoria Lower Glacier) that join at a broad median shear zone. Evidence from the margins suggest that both are currently retreating. Algae in a block of frozen stratified sediment from within the ice of the terminal margin has a radiocarbon age of 20 200 ± 2400 year BP (NZ 6531 A), indicating that the glacier has advanced since that time. Superposition of ice levels of Ross Sea I glaciation on a radio echo–sounding profile of bedrock beneath the glacier indicates that it is unlikely that Ross Sea I ice entered the valley. The radiocarbon date supports this finding.

The Reformation in Moray and Mr Robert Pont

2019 ◽  
Vol 39 (1) ◽  
pp. 1-39 ◽  
Author(s):  
Frank D. Bardgett
Keyword(s):  
Reformed Church ◽  
The North ◽  
The Reformation

The province of Moray, in the north of Scotland and on the fringe of the Gaelic highlands, is not noted for any early support for Protestantism though, after 1560 Moray's churches were staffed, in so far as they were staffed, with a conforming ministry. The General Assembly's commissioner in the province, 1563–74, was Mr Robert Pont, one of the ‘most eminent’ ministers of the early reformed church. His role in ‘planting kirks’, however, has not previously been assessed by studies of the Reformation in his province. This article reviews what can be gathered of the development of a reformed ministry in the burghs and parishes of Moray during Pont's time in the region.

A description of two new species of water mites of the genus Torrenticola Piersig, 1896 (Acariformes: Hydrachnidia: Torrenticolidae) from the Krasnodar Kray, Russia

2013 ◽  
Vol 22 (2) ◽  
pp. 181-188
Author(s):  
P.V. Tuzovskij
Keyword(s):  
New Species ◽  
Mite Species ◽  
Running Waters ◽  
Water Mites ◽  
North Caucasus ◽  
Water Mite ◽  
The North ◽  
Two New Species

Two new water mite species, Torrenticola amplexella and T. krasnodarensis, from running waters of the North Caucasus (Krasnodar Kray) are described with illustrations.

scholarly journals Toward a global reference database of COI barcodes for marine zooplankton

2021 ◽  
Vol 168 (6) ◽  
Author(s):  
Ann Bucklin ◽  
Katja T. C. A. Peijnenburg ◽  
Ksenia N. Kosobokova ◽  
Todd D. O’Brien ◽  
Leocadio Blanco-Bercial ◽  
...  
Keyword(s):  
Species Diversity ◽  
Dna Sequences ◽  
Reference Sequence ◽  
Global Ocean ◽  
Reference Database ◽  
Data Repositories ◽  
Marine Zooplankton ◽  
The North ◽  
Coi Sequences ◽  
Taxonomic Groups

AbstractCharacterization of species diversity of zooplankton is key to understanding, assessing, and predicting the function and future of pelagic ecosystems throughout the global ocean. The marine zooplankton assemblage, including only metazoans, is highly diverse and taxonomically complex, with an estimated ~28,000 species of 41 major taxonomic groups. This review provides a comprehensive summary of DNA sequences for the barcode region of mitochondrial cytochrome oxidase I (COI) for identified specimens. The foundation of this summary is the MetaZooGene Barcode Atlas and Database (MZGdb), a new open-access data and metadata portal that is linked to NCBI GenBank and BOLD data repositories. The MZGdb provides enhanced quality control and tools for assembling COI reference sequence databases that are specific to selected taxonomic groups and/or ocean regions, with associated metadata (e.g., collection georeferencing, verification of species identification, molecular protocols), and tools for statistical analysis, mapping, and visualization. To date, over 150,000 COI sequences for ~ 5600 described species of marine metazoan plankton (including holo- and meroplankton) are available via the MZGdb portal. This review uses the MZGdb as a resource for summaries of COI barcode data and metadata for important taxonomic groups of marine zooplankton and selected regions, including the North Atlantic, Arctic, North Pacific, and Southern Oceans. The MZGdb is designed to provide a foundation for analysis of species diversity of marine zooplankton based on DNA barcoding and metabarcoding for assessment of marine ecosystems and rapid detection of the impacts of climate change.

scholarly journals Ground ice in the Northern Foothills, northern Victoria Land, Antarctica

2004 ◽  
Vol 39 ◽  
pp. 495-500 ◽  
Author(s):  
Mauro Guglielmin ◽  
Hugh M. French
Keyword(s):  
Oxygen Isotope ◽  
Ross Sea ◽  
Progress Report ◽  
Ground Ice ◽  
Lake Ice ◽  
Near Surface ◽  
Victoria Land ◽  
Different Types ◽  
Glacier Ice ◽  
Surface Ice

AbstractThis progress report classifies the different types of ground-ice bodies that occur in the Northern Foothills, northern Victoria Land, Antarctica. Oxygen isotope variations are presented, but interpretation is kept to a minimum pending further investigations. Surface ice, as distinct from moving glacier ice, occurs in the form of widespread buried (‘dead’) glacier ice lying beneath ablation (sublimation) till, together with perennial lake ice, snow banks and icing-blister ice.’Dry’ permafrost is uncommon, and interstitial ice is usually present at the base of the active layer and in the near-surface permafrost. This probably reflects the supply of moisture from the Ross Sea and limited sublimation under today’s climate. Intrusive ice occurs as layers within perennial lake-ice covers and gives rise to small icing blisters. Small ice wedges found beneath the furrows of high-centered polygons appear to agree with the model of sublimation-till development proposed by Marchant and others (2002).

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