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Weddell seals (Leptonychotes weddelli) are the most southerly breeding of all mammals and breed on the fast-ice around the shores of the Antarctic continent. Weddell seals display a polygynous mating system, with operational sex ratios (OSR) ranging from 3:1 to 8:1.
Three mutant polypeptides of the type I 37-residue winter flounder antifreeze protein have been synthesized. All four threonine residues in the native peptide have been mutated to serine…
The moss Hennediella heimii constitutes a significant proportion of the terrestrial flora of East Antarctica, especially in the McMurdo Dry Valleys region of southern Victoria Land. This is the first investigation of the extent of genetic variation within a population of Hennediella heimii. RAPDs…
The RAPD technique (Random Amplified Polymorphic DNA) was used to assess the level of genetic diversity in Bryum argenteum from Ross Island and Southern Victoria Land, Antarctica. Samples were collected from three transects at different sites…
Subantarctic Macquarie Island has substantial areas of feldmark on its plateau above 200 m altitude. Samples of the substrate (5.5 cm in depth) from bare areas of feldmark contained viable propagules of bryophyte species found at adjacent and distant sites on the island.
Terrestrial ecosystems of southern ocean islands have enjoyed renewed attention recently. Stimulated by findings that their climates are changing dramatically, outcomes include an enhanced understanding of the biogeography of this region…
Natural variability in surface reflectance was studied in 3 species of moss (Grimmia antarctici, Bryum pseudotriquetrum and Ceratodon purpureus) in continental Antarctica. The moss community is well developed in Wilkes Land, eastern Antarctica…
Two cryophilic Desmotetra species, D. aureospora, sp. nov., and D. antarctica (Fritsch) Ling appear to be unique to the southern hemisphere snow ecosystem, or at least to the Windmill Is. region, Antarctica.
A novel alphavirus was isolated from the louse Lepidophthirus macrorhini, collected from southern elephant seals, Mirounga leonina, on Macquarie Island, Australia. The virus displayed classic alphavirus ultrastructure and appeared to be serologically different from known Australasian alphaviruses.
In recent years there has been increasing pressure at the international level to improve environmental management in the Antarctic. The Protocol on Environmental Protection to the Antarctic Treaty (the Madrid Protocol)…
Oxyphotobacteria ascribed to the genera Synechococcus and Synechocystis are widely distributed in Arctic and Antarctic lakes, yet they are poorly represented in the marine polar environment. Arctic lakes contain phycoerythrin-rich as well as phycocyanin-rich … picoplankton…
A review of popular writing on the subject of preservation of historic sites in Antarctica, including buildings, graves and artefacts, has revealed many misconceptions about the existence and cause of deterioration problems.
Measurements of the mid-infrared sky brightness at the South Pole throughout the winter of 1998 show that the sky background is … extremely low and stable. For 50% of the time, the flux in the 8.78 to 9.09 ?m window is below 50 Jy per square arcsecond.
We are using molecular genetics techniques to investigate (a) the overall level of genetic diversity in Antarctic mosses, (b) the spatial arrangement and mutation levels within populations, (c) their taxonomic relationships and origins, (d) the effect of climate change on mutation levels, and (e)…
As well as determining the amount of solar radiation available for photosynthesis, the surface reflectance and absorptance characteristics of plants are their first defence against damaging effects of solar radiation. The solar spectrum can be damaging to plants in many ways. At shorter wavelengths…
A group of strains with potent extracellular enzymic activity were isolated from the surfaces of the chain-forming sea-ice diatom Melosira and from an unidentified macrophyte collected from the Eastern Antarctic coastal zone.
The growth rates of heterotrophic nanoflagellates (HNAN), mixotrophic cryptophytes, dinoflagellates and ciliates in field assemblages from Ace Lake in the Vestfold Hills (eastern Antarctica) and Lakes Fryxell and Hoare (McMurdo Dry Valleys, western Antarctica)…
Quartz stone sublithic cyanobacterial communities are common throughout the Vestfold Hills, Eastern Antarctica (68 degrees S 78 degrees E) contributing biomass in areas otherwise devoid of any type of vegetation. In this study…
Global Positioning System (GPS) satellites now provide a major source of data used in the study of the ionized regions that … surround the Earth. With the greater use of GPS satellites in this role…
Recent time-series measurements of atmospheric O2 show that the land biosphere and world oceans annually sequestered 1.4 ± 0.8 and 2.0 ± 0.6 gigatons of carbon, respectively between mid-1991 and mid-1997. The rapid storage of carbon by the Land biosphere from 1991 to 1997 contrasts with the 1980s…
Bryophytes are sensitive indicators of environmental change and with climate change being expected to occur first at high latitudes, Antarctic bryophytes are ideal study systems for the detection of climate change effects.
Surface sediments (0-25 cm) from Ace Lake (eastern Antarctica), a saline euxinic lake, were analyzed to study the early incorporation of reduced inorganic sulfur species into organic matter. The apolar fractions were shown to consist predominantly of dimeric (poly)sulfide linked C-27-C-29 steroids.
Eighteen paired sites (adjacent to vs away from sea bird nests) and six transects (downslope of nests) across Vestfold Hills were sampled for vegetation, soil nutrients, soil water content and percent rock cover. Three moss and 17 lichen species were recorded…