Deep Lake in Antarctica is so salty that it stays liquid at temperatures down to minus 20 degrees Celsius (minus 4 degrees Fahrenheit).
Dr. Jan Michels, Christian-Albrechts-Universi
It might sound a bit cramped, but there's an entire world of organisms that can call a drop of water their home. And, up close, they look practically out-of-this-world. Each year, the Nikon Small World competition sets out to collect some of the best microphotography. Take a look at some of this year's most stunning images of creatures that live in water. This photo from Dr. Jan Michels of Christian-Albrechts-Universität zu Kiel in Kiel, Germany shows Temora longicornis, a marine copepod, from its ventral view at 10 times magnification.
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Frank Fox, Fachhochschule Trier/Nikon Small W
This microphotograph shows the diatom Melosira moniliformis at 320 times its size.
Jonathan Franks, University of Pittsburgh/Nik
This algae biofilm photographed up-close makes what's usually referred to as "pond scum" look like art.
Michael Shribak and Dr. Irina Arkhipova, Mari
This Philodina roseola rotifer was alive and well when this microphotograph was taken.
Dr. Ralf Wagner/Nikon Small World
This microphoto shows a water flea flanked by green algae.
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Charles Krebs Photography/Nikon Small World
Warfare in a water droplet! This microphoto shows a Hydra capturing a water flea at 40-times magnification.
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Dr. John H. Brackenbury, University of Cambri
One of the ultimate human pests -- the mosquito -- begins life as larvae, here shown suspended in a single droplet of water.
Gerd A. Guenther/Nikon Small World
Ever wonder what sex between two freshwater ciliates looks like magnified at 630 times its actual size? Now you know!
Joan Rohl, Institute for Biochemistry and Bio
This freshwater water flea is shown at 100 times its actual size.
Wolfgang Bettighofer/Nikon Small World
Closterium lunula, a kind of green alga, is shown here. This particular specimen came from a bog pond, according to the photographer.
John Gaynes, University of Utah/Nikon Small W
While it may resemble a visitor from outer space, this is what a zebrafish embryo looks like under a microscope, three days after being fertilized.
Dr. Carlos Alberto Muñoz, University of Puer
This microscopic crustacean appears yellowish-orange because it is mounted in Canada Balsam with crystals and other artifacts.
Microbes living in Antarctica's saltiest lake swap huge chunks of genetic material as a means of surviving their harsh environment, a new study finds.
The single-celled organisms, called haloarchaea for their salt-loving ways, are biologically distinct from bacteria, algae and other tiny creatures that can thrive in extreme settings.
Their Antarctic home is a deep lake in the Vestfold Hills severed from the ocean more than 3,000 years ago. Appropriately named Deep Lake, the basin sits 50 meters (165 feet) below sea level. Deep Lake is so salty that it's never been known to freeze, even at temperatures below minus 4 degrees Fahrenheit (minus 20 degrees Celsius).
Little else lives in Deep Lake except haloarchaea. For years, scientists have been analyzing the microbes to see what makes them thrive in the strange environment, and for clues to possible life on other planets. (Life on Ice: Gallery of Cold-Loving Creatures)
One unusual survival technique has now been found: The handful of haloarchaea species in Deep Lake exchange DNA, according to a study published yesterday (Sept. 30) in the journal Proceedings of the National Academy of Sciences.
Though each species is specialized and has its own niche, such as eating proteins or sugars, they come together and trade chunks of DNA, some as long as 35,000 letters of code, a team led by Rick Cavicchioli, a microbiologist at the University of New South Wales in Australia, discovered.
"Our research shows these (haloarchaea) swap much more genetic material with each other than has been observed in the natural environment before. Long stretches of virtually identical DNA are exchanged between different genera, not just species," Cavicchioli said in a statement. "Despite this rampant gene swapping, the different species are maintained and can co-exist because they have evolved to exploit different niches and consume different food sources." (Genus is the classification above species.)
Another consequence of life in the cold zone is slowed reproduction. The lake haloarchaea reproduce only six times a year, the researchers found.
Cold-loving extremophiles also live in permafrost, or permanently frozen ground, and in lakes buried beneath Antarctica's ice sheet. Microbes also happily make their home within the ice sheet itself.
Email Becky Oskin or follow her @beckyoskin. Follow us @livescience, Facebook & Google+. Original article on LiveScience.com.
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