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Scientists Confirm Life Under Antarctic Ice
MikeChino writes A new paper by a group of researchers from Montana State University confirms that life can survive under antarctic ice. Researchers led by John Priscu drilled down into the West Antarctic Ice Sheet and pulled up organisms called Archaea. These organisms survive by converting methane into energy, enabling them to survive where there is no wind or sunlight, buried deep under the ice.
They better not stir them up
putting the 'B' in LGBTQ+
What surprises me is the "the source of the ammonium and methane is most likely from the breakdown of organic matter that was deposited in the area hundreds of thousands of years ago when Antarctica was warmer and the sea inundated West Antarctica." part.
If the methane was already readily available, why didn't the organisms multiply to use up the methane faster?
I guess some organism breaks down the organic matter to methane and thereby limits the availability for the methane eating organism. But over the course of a hundred thousand years I feel that such a limited ecosystem should have exhausted the resources long ago.
What is the limiting factor that prevents this?
This life is not necessarily in a circle of life. It can be methane formed in a similar way as natural gas or swamp gas. These can be pockets of methane that can eventually be depleted.
I'm just speculating though. As a good /. member, I didn't even rtfa.
Researchers led by John Priscu drilled down into the West Antarctic Ice Sheet and pulled up organisms called Archaea
Were they called this before we pulled them up? Did they tell us they were called Archaea?
If I recall from my comic books Archaea tried to breed with Betty and Veronica.
I knew they were frigid, but this is the first I'm hearing about their meth usage.
I'm a biogeochemist (haven't worked on this project or in the arctic, but I know about microbial communities and organic matter decay) and while this is certainly interesting, it is not very strange.
What you have to remember is that organic matter decays very quickly (and some types decay faster than others, e.g. DNA seems to decay faster than lignin), but only if it has plenty of oxygen. For this same reason we still find oil after millions of years, it is anaerobically decayed organic matter. Furthermore, if you look closely at the chemical composition of the oil, you can determine how old it is by looking at how far it has decayed rather than looking at the overall mass which will barely have changed essentially (so rather than seeing C30H60 + 45O2 -> 30CO2 + 30H2O it would look more like C30H60 -> 2C15H30 followed by C15H30 -> C7H14 + C8H16, which are very slow steps)
In Antarctica, we have a very similar environment, except now our low oxygen concentration isn't because the organic matter was buried under sediment but under ice. Add to this that we have subzero temperatures (low temperatures reduce the rate of organic matter decay) and the case is starting to add up for long term preservation of organic matter. So while this system will certainly run out of organic matter (and thus ammonia and methane), it will do so very slowly.
Since I don't know the exact individual species involved in this ecosystem it becomes very hard to say which step exactly is limiting the growth. However, I can tell you that ammonia is converted into other more oxidized nitrogen species (such as nitrite and nitrate) relatively easily compared to the rate of methane conversion. So my guess would be that either the limiting step is the methane production, the system lacks enough other nutrients like phosphate (which, interestingly, is generally a limiting factor in marine systems), or there is not enough sulfate (methane is generally broken down by microbes by using sulfate as an oxidizer, if you get a sediment sample with a lot of methane in it, you will generally find not much sulfate remains).
I hope this helps to clarify a few things, but without knowing the actual microbial community and depositional environment etc. I can't say much for certain about the actual limiting factor.