Microbial Life Found In Trinidadian Hydrocarbon Lake 141
KentuckyFC writes "Pitch Lake is a poisonous, foul-smelling hell hole on the Caribbean island of Trinidad. It is filled with hot asphalt and bubbling with noxious hydrocarbon gases and carbon dioxide. Various scientists have suggested that it is the closest thing on Earth to the kind of hydrocarbon lakes they can see on Saturn's moon Titan. Now a group of researchers has discovered that the lake is teeming with microbial life which is thriving in the oxygen-free environment with very little water, eating hydrocarbons and respiring with metals. Gene sequence analysis indicates that these bugs are single-celled organisms such as archea and bacteria. The researchers say the discovery has exciting implications for the possibility of life on Titan. There is a growing sense that Titan has all the ingredients for life: thermodynamic disequilibrium, abundant carbon-containing molecules, and a fluid environment. There is also evidence that liquid water may not be as important for life as everybody has assumed, since some microorganisms can make their own water by chewing on various hydrocarbons. That may make Titan an even better place to look for life than previously thought."
water (Score:4, Insightful)
"since some microorganisms can make their own water by chewing on various hydrocarbons"
It's a chicken-and-egg issue. Why should something evolve that can create something that it needs to exist in the first place? It doesn't seem to be very likely that something organism evolves out an environment without water, that later needs water. But, it may evolve from a wet environment to a state where it later no longer depends on pre-supplied water.
Re:Has populations between 10^6 to 10^7 cells/gram (Score:3, Insightful)
Depends on where you sample your seawater. But the cells here are much smaller. And Titan is unlikely in my mind given the 200K+ thermal difference. Life is clever, but the laws of physics catch up to you. Besides, we're talking long chain vs short chain hydrocarbons.
Oryx (Score:2, Insightful)
An Oryx doesn't drink water, but it pees.
A chicken does drink water, but it doesn't pee.
Re:necessity of water (Score:2, Insightful)
... why do you have to base it from whats abundantly around you in your tiny micro speckle of the universe and project it on everything?
You don't. However, if you're going to theorize life without this chemical that plays a crucial role in so many chemical processes that are used by life as we know it, and expect to be taken seriously, you need to find replacements that are likely to exist instead of water in there alien environments and will be able to serve in its stead, or you need to come up with replacement life processes.
Presumably, you've done neither... which would make your speculation on life without water about as scientific as speculating life based on fairy-dust.
Get back to us when you've worked out this possible alien biochemistry, then we can start seeing how viable it would be given the alien environments we might fight the building blocks for it, and how well it operates compared to the processes we know.
Re:Family resemblance? (Score:5, Insightful)
To the best of my knowledge all life on earth (at least all life that has been investigated at the DNA/RNA level) seems to have considerable similarities, which implies a relationship, perhaps a common origin point.
Which is of course what the theory of evolution tries to explain, with considerable success.
While it is certainly remarkable how flexible life on Earth is, we also have to keep in mind that it has evolved from a common, water-based origin, and the fact that archaea can adapt to living in tar with access to very little water does not mean that life could have started in such an environment.
The thing about water is that it is an altogether remarkable substance; it has a number of properties that are not found together in many other substances - I am certainly not aware of any - and there are reasons to believe that life (at least chemical life as we know it: with DNA/RNA, proteins etc) needs this constellation of properties to arise. We simply don't know if life can arise in other environments; our understanding of what life is at the deepest level is still very patchy.
Re:necessity of water (Score:2, Insightful)
it has everything to do with water's unquie properties. it's non corrosive, non reactive, is liquid at reasonible temperatues and is able to transport other elements without contamination.
life isn't going to exist at 1000c or -200c, and the mechanics of life ie. a fluid transport mechanism, won't work with solids.
if you can offer a viable alternative i'm all ears
Re:What's the temperature Kenneth? (Score:5, Insightful)
You don't need a high temperature to drive the chemistry of life - you need a temperature gradient so that work can be done by transferring heat energy from one location to another. Titan has this due to internal heating from tidal forces, as has Europa. Life may operate at a slower pace in a cold environment, but the right catalysts could improve this.
oxygen (Score:4, Insightful)
Our (very) distant ancestors evolved and thrived in an enviroment without significant amounts of oxygen; heck, it was most likely a poison to them. But then a group dumping it in large amounts showed up, and the rest is history...
Now, it even seems it's quite possible that, what was once a dangerous byproduct, enabled explosion of life later on.
Re:Oryx (Score:3, Insightful)
They don't drink but they do ingest water as a constituent of the solid foods they eat. Dessication works as a form of preservation or mummification precisely because practically nothing in nature will eat anything devoid of water.
Going back to the point, water-based life can only evolve in the presence of water. Water-based life faced with an scarcity of water may evolve the ability to synthesise its own water. It could then slowly adapt to survive in a complete absence of water. (Compare with trees, which produce oxygen from carbon-dioxide, but would die in an environment that was initially oxygen.)
If a lifeform evolved to exist on hydrocarbons alone, in the absence of water, then it would have developed an efficient way to do so at a primitive level. It is extremely unlike that a two-step process of creating water would be more efficient. In the long-term, yes, as it would allow Earth-like evolution, but the immediate-term disadvantage would lead to any such strains extinguishing themselves and not getting the chance to go beyond the single cell.
Unlike hot-vent extremophiles, it's hard to argue that these bacteria could be the source of life as they live in hydrocarbons, which are the result of a not-yet-fully-understood process involving dead organic matter.
HAL.
Re:necessity of water (Score:4, Insightful)
I don't know what's more amazing - that you can post something that is so wrong, or the fact that someone modded you up.
the reason for us assuming the need for water has nothing to do with projecting our requirements on the rest of the universe.
This is hilarious - you say that projection has nothing to do with it, then you proceed to try to prove this point by projecting human requirements.
it's non corrosive, non reactive
BZZT. Water is very corrosive and reactive. It is known as "the universal solvent" for a reason.
is liquid at reasonible temperatues
How does one define "reasonible"[sp]? Oh yeah - by projecting our own requirements.
life isn't going to exist at 1000c or -200c
More projecting.
the mechanics of life ie. a fluid transport mechanism, won't work with solids.
Aside from the fact that this is just still more projecting, why exactly is water the only substance that fits this bill? Why could another compound not fill the same purpose?