Cyanobacteria Fossils Disproven !

[CraigS]

It appears that the supposed oldest examples of life on our planet -- 3.5 billion-year-old bacteria fossils found in Australian rock called Apex Chert -- are nothing more than tiny gaps in the rock that are packed with minerals.

Tea-leaf gazing I hear you say, eh ?

Source: Research overturns oldest evidence of life on Earth

“Bacteria are basically little bags of goo, and they’re not easily fossilized,” said Alison Olcott Marshall. “The idea that you would have this tiny bacterium preserved for 3.5 billion years is not very likely to happen. The second problem is that they are morphologically so simple — they’re just circles and rods. There are lots of things in nature that make circles and rods.”
...“This work has direct implications for looking for life on Mars,” said Craig Marshall. “If we’re having problems here with ancient Earth sediments and there’s a huge debate, we want to try and be more stringent with our analytic techniques. We don’t want a repeat of the announcement in 1996 that, ‘Wow, we found life on Mars.’ I can’t recall the timeframe of how many days or weeks until they said, ‘Well, maybe we haven’t.’ If we tighten up our ways of looking for ancient biology, this is going to be very applicable for Mars, particularly the ExoMars European mission in 2018 that will take on board a Raman spectrometer.”

This is interesting in the light of the recent declaration by Richard Hoover, and his conclusions about finding 'life' from what he says are fossilised cyanobacteria filaments.

In spite of the too-ing and fro-ing, at least its good input for the forthcoming hype when they find something unusual on Mars .. (a foregone conclusion, it seems).

A parting quote …

The second problem is that they are morphologically so simple — they’re just circles and rods. There are lots of things in nature that make circles and rods.”

Cheers

[renormalised (Carl)]

Just means they need to do more sampling and looking for the old bugs.

However, what the researchers here need to be mindful of is they don't know how much the other minerals (in this case hematite) may have replaced the carbon in any bacteria that may have been fossilised. They may actually have bugs that have been completely replaced by other minerals during the fossilisation process. I've seen plenty of fossils in just such a state...it wouldn't matter what you did to analyse them, you'd find no organic material (or its remnants) left.

[CraigS]

Pattern recognition is important too, eh ?

Got to be careful with that though .. patterns can be deceiving.

I find it amazing that we have such difficulty in recognising life forms … either past ones or present !

Cheers

[renormalised (Carl)]

Originally Posted by CraigS

Pattern recognition is important too, eh ?

Got to be careful with that though .. patterns can be deceiving.

I find it amazing that we have such difficulty in recognising life forms … either past ones or present !

Cheers

Yes, but you have to be careful, as you have said.

Sometime scientist can over analyse and be too cautious.

[CraigS]

Originally Posted by renormalised

Yes, but you have to be careful, as you have said.

Sometime scientist can over analyse and be too cautious.

This is an interesting topic (and off-topic, also .. its Ok .. I started the thread)…

The scientific approach calls for breaking a problem down into its constituent components, to look for the simplest building blocks for which we understand the behaviours of. When one does this, one tends to lose track of the big picture.

Recently, this earthquake prediction business that I'm on about, has reminded me of the Complexity/Chaos approach to complex systems which normally appear meanlinglessness in their constituent forms.

Perhaps we need more of these kinds of approaches to complex problems?

Cheers

[mswhin63 (Malcolm)]

think we need to spend more money on getting onto an asteroid take some samples there.

[CraigS]

Originally Posted by mswhin63

think we need to spend more money on getting onto an asteroid take some samples there.

What do we do with the samples, though ?


Cheers

[Astro78]

Interesting. The oldest life known is actually Stomatolites though, structures of cyanobacteria as opposed to sediment as with the Apex Chert. Apex chert has biomarkers for life only. Big difference. We have biomarkers on martian meteorites such as in ALH84001 but that doesn't prove life (to most).

Anyway I have the actual paper if anyone is interested (it's a 1.1meg PDF...Mods?) Note they still say it's consistent with life....Isotope ratios of C13 still indicate life.