Scientists Look at Martian Salt for Ancient Life

eldavojohn writes "Is there life on Mars? Maybe not, but a better question might be whether or not it has ever existed on Mars? Scientists are claiming that the best indication for this will be in newly found evaporated salt deposits on Mars which they can use to check for cellulose. Here on earth, tiny fuzzy fibers have been found in salt dating back almost 250 million years making it the oldest known evidence of life on earth. Jack Griffith, a microbiologist from UNC, is quoted as saying, 'Cellulose was one of the earliest polymers organisms made during their evolution, so it pops out as the most likely thing you'd find on Mars, if you found anything at all. Looking for it in salt deposits is probably a very good way to go.'"

slightly inaccurate summary

[cowscows]

The article summary says that the cellulose found in 250 million year old salt is the oldest known evidence for life on Earth. That's not true, there's ample of evidence of life for billions of years before that. The article states that the 250 million year old salt is the oldest biological substance known, which is pretty cool, but there are plenty of other types of evidence for life besides just finding dead tissue.

Re:slightly inaccurate summary

[MightyMartian]

Start here. It also includes all the necessary references for going to the primary literature if you think all those evil atheist scum in talkorigins.org are just making it up:

http://talkorigins.org/faqs/faq-age-of-earth.html [talkorigins.org]

In fact, I suggest you probably spend some time at that site.

Re:Return Sample?

[SatanicPuppy]

I don't honestly think there will be any evolutionary pressure, simply because there is no vehicle for it. In the case of livestock viruses, those viruses are passed around the animal populations for huge amounts of time before one manages to jump the divide. We live in close proximity to the livestock, so there is a good chance, given enough time, that a virus will mutate in just the right way, and that that mutation will happen in the right time and place to find a suitable host.

None of that applies to a theoretical martian virus that's got no growth vector and no suitable host animal that it's evolved to live in, that we like to hang out with. It would have to have us nailed the first time, no tests, no practice. That's pretty damn unlikely.

The asteroid thing is of course possible, but again pretty unlikely. In that scenario, it'd be more likely that we've already been infected with martian bacteria and have built up immunity than it is that our whole ecosystem is parallel to theirs, and their theoretical hostile bacteria are out there now, waiting.

Re:Return Sample?

[Geoffrey.landis]

You've been watching too much sci-fi...It's unlikely that something from such a wildly different evolutionary line would even be infectious to us. It's still pretty rare that diseases jump species here and everything on Earth is pretty closely related, genetically speaking.

Don't bother with that-- if Martian organisms are halophilic, they could not survive in a salt concentration as low as that in our bloodstream, or our oceans; they would literally fall apart.

...and if they're not halophilic, they wouldn't survive on Mars.

Re:Why?

[MightyMartian]

I honestly don't know enough about complex chemistry to answer any question like that. I would suspect, however, that for any carbon-based life, carbohydrates are going to be an absolute requirement for releasing and utilizing energy (ie. ATP). In that case, you're likely going to find related chemistry (starches, cellulose, etc.) in such ecosystems, even if they are unrelated to or only distantly related to life on this planet.

Now, of course, if life is silicon based, then you're right, you would have an entirely alien chemistry, and would have to look for very different things.