Until recently the ice cover of the Antarctic Continent was considered to be totally lifeless. All living beings are localized in the coastal zone of the Antarctica, and nothing alive dwells the centre of the dome, where winter frosts reach 80 degrees below zero and strong permanent winds blow. This is what the scientists have thought, until 15 years ago S.S. Abyzov (PhD (biology) from RAS Institute of Microbiology) has found microorganisms inside Antarctic ice – bacteria, yeasts and fungi. They appeared to be buried deep inside ice mass – 2500 m. The age of this ice is not less than 300 thousand years. Microorganisms are there under anabiosis, but some of them can be reanimated when put in a growth medium.
At that time Mr. Abyzov has detected the ability of microorganisms to maintain super-long-term anabiosis for the first time, but as a discovery this fact has been registered only in 1995. Mr. Abyzov’s group of scientists continues its research in the Antarctica and has recently received sensational results from the 3500 m depth.
The scientists collect samples from the well on the “Vostok” station, which is expected to pierce the whole Antarctic ice cover. The microbiologists have asked experts from Saint Petersburg Institute for Mountain Research to design a special microbiological drilling unit. It cuts the core out of an ice pillar taken from the well, then the core melts over the flask. Sterility is very important here, not a single microorganism should get into the flask from outside. Then the flasks are sealed and taken to the laboratory for analysis. Melt water partly passes through the bacterial filters, then these filters are dyed and microorganisms are counted. This way the scientists have found out that one ml of melt water contains several thousand of microbial cells.
What are these microbes? They are bacteria, diatomic algae, yeasts and fungi. The researches have also isolated a new species of actinomycetes (bacteria that look like fungi) and named it “antarctic”. Ancient microbial flora generally consists of the same microorganisms, existing nowadays. Microbial cells, extracted from ice, were plated on a growth medium. Some of them have started growing and dividing, waking from a thousand year sleep. The scientists have also used the precise tracer technique. They added C14 labeled hydrolyzed protein solution to the samples. Only living cells consume radioactive carbon. The amount of them decreases with depth. Viable forms appeared to exist even deeper than 3500 m.
Now the scientists have reached the depth of 3611 m. The well has stopped above the subglacial lake whose age is about one million years. Glaciologists have found out that it never totally freezes, only its surface layers turn to ice. Well drilling has been stopped until an international committee solves the issue of lake’s ecological safety. Microbiologists have taken their last samples from the bottom ice layers, which were formed from lake waters. Some microorganisms were found in these samples – several hundred cells per one ml of melt glacial water. These samples are still analyzed but, according to preliminary data, they are inhabited by various fungi and bacteria.
The scientists have found an interesting pattern while comparing their data with data of glaciologists. The amount of microorganisms and dust particles is different in different ice layers. When they matched the changes’ curve with our planet climate conditions, the largest amount of dust and microbes appeared to be during global cooling periods. The scientists explain this fact, saying that when the climate gets colder, the air becomes dryer, World ocean shelf partly exposes to the winds, which grow stronger and bring lots of micro-material to the forming glacier. But temperature drop is fatal for microorganisms; such layers almost do not contain living cells.
So microorganisms are able to survive in ice for hundreds thousand of years. This discovery is very interesting for extraterrestrial life issue research. According to a hypothesis of Swedish chemist Svante Arrhenius, suggested as early as in the beginning of XXth century, the living matter is immortal and travels from planet to planet in the form of fetuses. Modern science denies this hypothesis, but it looks quite reasonable in view of new data. How do the fetuses travel? They can use ice for this purpose. It can protect living cells from tough cosmic rays and dryness. And low temperatures help cells to be dormant during their long space journey for hundreds thousands of years.
Mr. Abyzov thinks that the Antarctic ice cover can be a model for extraterrestrial life probability research and life transfer in outer space. Together with American colleagues the scientist plans to explore Mars ice caps, and comet ice nuclei and Jupiter satellite – Europe – studies are his future projects.