Anyone catch this article on Science Daily? Would be interesting to hear what Francis Crick would have had to say about this...

SImple life form may have existed 700 million years earlier than previously thought

The article talks about traces of light carbon trapped in diamonds and graphite. It's a slight possibility that an organic life form MAY have created those pockets of light carbon.
But it's all total speculation at this time.
There isn't much here to day except for , "Hey.. Maybe... Just maybe there might have could been..."

So much for sensationalized drama...

It generally takes more than "Hey.. Maybe... Just maybe there might have could been..." to get a paper into Nature.

http://www.nature.com/nature/journal...AD58EEFB0C3284

The median istopic fractionation of -31 per mil is well beyond what would normally be considered as indicating inorganic processes (-6 per mil in younger diamonds is normally considered as indicative of a possible biogenic carbon source). Not proof of life, but strongly suggestive of it and certainly more than "total speculation".

Jon

In that case, I stand corrected.

Sometimes, the finer details really help...

I had hoped that the lead author would be speaking at the coference I am going to tomorrow, but no luck

But finding these diamonds is quite an extraordinary saga of persistance and analytical precision. The Jack Hills conglomerate is ~3.6 Ga, and zircons are less than 1% of the rock. The zircon grains are perhaps a mm across, or smaller. Only a fraction of these are ancient (>4.0 Ga). The diamonds themselves are found in only a very few of these and are miniscule.

Jon

It's very interesting and the technique is similar to what was used to determine an earlier 3.8 billion year old figure for life:

http://news.nationalgeographic.com/n...amicrobes.html

Some explaination other than life may be found for the isotope ratios, but that seems unlikely to me.

Of course it is possible that life may have arisen and gone extinct several times in earth's early history due to bombardment or whatever. If this turns out to be the case it would suggest that life isn't too improbable and may be common. However, I would guess that life underground could survive a lot of pounding provided the earth's crust didn't get too cooked.

While its nice to think life got started on earth almost immediately under the right conditions, the earlier the start point the longer it took for our evolution to occur. Still what's a billion years in the grand scheme of things.

The signs seem to be pointing to: evolution of nanobacteria and then bacteria: easy. Going from bacteria to anything more complicated (e.g. something with a nucleus): very very hard. (incidentally, the time between bacteria and cell with nucleus was a lot more than the time between cell with nucleus and multicellular--plenty of reasons the former is a lot harder than the latter--both are probably the result of parasite -> symbiosis -> merging of the life forms.)

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

personal page: http://blog.astrosketches.info

Yeah--just like cold fusion and Martian fossils!

The abstract itself says "Low Δ¹³C_PDB values may also be produced by inorganic chemical reactions, and therefore are not unambiguous evidence for life on Earth as early as 4,250 Myr ago." But it certainly adds "élan" to the debate, and is sure to generate much "buzz" for Nature and so keep those $199 subscriptions rolling in! I'd like to read the article itself for more details; too bad they want $30 USD for it.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

Hey are you at AESC 2008?

if so, check out Dynamic earth session at 1440 tomorrow by Bob Nicoll. Its a Ordovician paleobiogeography paper I am co-authoring.

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plenty of woo, at the hotel hoagaland...

Fascinating!

And so now there's even less time to go from inorganic goo to Life.

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"Where the telescope ends, the microscope begins. Which of the two has the greater view?" - Hugo

"Men occasionally stumble over the truth, but most pick themselves up and hurry off as if nothing had happened." - Churchill

So that means it had to be panspermia, right?

Not necessarily. Sorry.

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Yes, they laughed at Einstein, but only because of his silly hairstyle; no one was actually laughing at his science.

Nah, it only means that Life from inorganic goo occurred rapidly and easily on Earth, if in fact it originated on Earth.

Right.

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"Where the telescope ends, the microscope begins. Which of the two has the greater view?" - Hugo

"Men occasionally stumble over the truth, but most pick themselves up and hurry off as if nothing had happened." - Churchill

Hmmm, I'll have to read the actual paper. But it would be a major finding if it holds up... the evidence for life from the Isua supracrustal rocks at ~3.8 Ga is not unambiguous either. And at least one of those detrital zircon grains is 4.4 billion years old...

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Do not taunt Happy Fun Ball.

If you get it, could you send me a copy of the pdf because they're charging $30 for it without a subscription. It looks interesting--but not $30 interesting.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

Interesting. If they are right they just moved back the origin of life 150 million years father than from today to the beginning of the paleozoic.

It also seems to me that if life was getting a foothold that early, we are prolly pretty likely to find some evidence of something that lived on Mars.

Got it. Send me a PM with your email address and I'll forward it along.

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Do not taunt Happy Fun Ball.

Excellent!

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

Both would be amazing:
(a) life arising several times on Earth,
or (b) life arising that early and surviving disasters underground to resurface later.

Hope to hear more about this!

If it's so easy to create life, then why can't we do it in the laboratory?

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin