Coldest life?

[Xyph]

Recently it seems there's been a lot of interest in the upper limit for the existence of extremophilic organisms, but I haven't been able to find very much on the lower limits of temperatures at which life would be feasible.

 

So, what organism at the moment is the record holder for (reasonably comfortable) survival at the extremely low temperatures? I've read -15°, but I'm not sure how up to date this is, as the site also listed 113° as the upper limit for hyperthermophiles, which I know has been recently surpassed.

 

Also, is there any theoretical lower temperature limit for life? Apparently at temperatures above 150° biological proteins should start to break down, making that a reasonable upper limit, but I haven't found anything on a lower limit.

[Daecon]

That's pretty interesting. I'd have assumed that liquid water would be needed for life, so any temperature range where water is either solid or gaseous would be ruled out...

 

I guess not.

[RyanJ]

Viruses (In spore form I believe, cold viruses af far as I remember) traveled into space, stayed on the moon for a while and were brought back alive. Apparently they were in some kind of stasis when and revided once brought back to Earth... thats amazing!

 

The limits of life are not easily definable, they set a standard and then find somethingthat ruins the rule... theremust be a limit but its not easy toput a pointer and say thats it - evolution does some interesting things.

 

It should also be noted that there may be life other then carbon based which could survive more extremes of temperature...

 

Cheers,

 

Ryan Jones

[zyncod]

Well, you do have situations where you can have superheated water (like in geysers or black smokers) or supercooled water (I don't know what natural situations you might find this in), where the water is still in the liquid phase.

[m4rc]

From The New Encyclopedia of Birds and http://www.aad.gov.au/default.asp?casid=3524 , "Emperor penguins endure the coldest conditions encountered by any bird...where the average temperature is -20C." They also breed in the middle of winter when "wind chill temperatures reaching down to minus 60ºC", they do not reveal what the actual temperature is. These penguins have adapted to live in the coldest place on earth. I believe that it is possible for life to adapt itself to even colder temperatures, however so far it has had no reason to do so because there is no place that is that cold.

[StarBreaker]

Well fundamentally, to say something is alive is to say that it has both motion and(or thus) the ability to replicate. At absolute zero (0 K/-273 C) molecules stop...correct? Since that is where molecular interaction stops, and its at the molecular level that life replicates, I wouldnt be surprised if life finds a way up to that point? Im probably overlooking some key elements though. Point them out.

 

Cant wait till 2015 when New Horizons makes it to Pluto/Kuiper belt! Theres gonna be some ground breaking science involved w/ that mission. Heres to Alan Stern and crew! Fantastic people. The upcoming Mars missions look promising for Astrobiolgy too. However...has anyone been paying attention to the FY2007 budget for NASA? Not looking so hot for the Astobiology arena etc. Its sad to think how many $billions are wasted on, lets say, Pro football, baskeball, baseball while folks at NASA have to sacrifice so many projects due to underfunding. Clearly this country is not interested in exploring and understanding our beautiful cosmos.....makes me angry.

[StarBreaker]

Oh yeah as mentioned, life can be suspended in hibernation at extreme colds and then come back to life after warming up, but as far as getting to a point of self replication...tt. At any rate, I find it very comforting that the more we study life, the more tenacious it proves itself to be.

[AzurePhoenix]

Well, as an active animal of higher complexity, Ice Worms actually live in ice and can survive below zero degrees celsius, and they actually melt at much higher temps.

 

Water bears on the other hand can go into a variation of hibernation that lets them surivive temepratures lower than negative 250 degrees celsius for a while. Real tenacious little buggers.

 

Snakehead fish can survive being frozen as well, as can a variety of frog, but at nowhere near the temps a water bear can.

[RyanJ]

hand can go into a variation of hibernation that lets them surivive temepratures lower than negative 250 degrees celsius for a while. Real tenacious little buggers.

 

Near absolute zero? Impressive.

 

Cheers,

 

Ryan Jones

[AzurePhoenix]

Indeed, and that's only one of a range of the waterbear's gifts - they tolerate intense heat and radiation, high pressure and low pressure as well. One was dormant for over a century and almost revived. Died partway through though. Through and through these little guys take the cake when it comes to the potential for survivability under adverse conditions.

[RyanJ]

Indeed, and that's only one of a range of the waterbear's gifts - they tolerate intense heat and radiation, high pressure and low pressure as well. One was dormant for over a century and almost revived. Died partway through though. Through and through these little guys take the cake when it comes to the potential for survivability under adverse conditions.

 

I did not know stasis was possible for such a long time. Thought muslcles and the brain its self detriorate aftrer prelonged periods of hibernation.

 

Also, if you want hard then cockroaches are tough things too... they can survive radiation 100 ties the human fatal dose. They have a enzyme (Orgroup thereof) that makes DNA repare more effective and faste...

 

Cheers,

 

Ryan Jones

[StarBreaker]

Wow! I just looked up the water bears. I was unaware of these creatures and its expained that they live virtually everwhere. Awesome.

[AzurePhoenix]

I did not know stasis was possible for such a long time. Thought muslcles and the brain its self detriorate aftrer prelonged periods of hibernation.

 

Also' date=' if you want hard then cockroaches are tough things too... they can survive radiation 100 ties the human fatal dose. They have a enzyme (Orgroup thereof) that makes DNA repare more effective and faste...[/quote'] Being tiny little invertebrates, they have a much simpler anatomy, no muscles to speak of, probably a very simple brain. Generally they wake up after a decade or so,which is nothing compared to some critters, but who knows how many decades they can make it before tehy just give out.

 

I believe I remember reading that the little guys could eat the roaches' fatal radiation dosage for breakfast I feel competitive

[RyanJ]

I believe I remember reading that the little guys could eat the roaches' fatal radiation dosage for breakfast I feel competitive

 

I'm impressed. Lets find out how they do it and get radiation protection for people

 

The same thing that helps block this radiation could be the cure for cancer they think - incorrect replication would be no more

 

Cheers,

 

Ryan Jones