Edit: perhaps "organic" was a poor choice of words. My meaning was that she disputed the claim that the artifact is in fact a fossil created by life, and suggested that it might be a geological formation of some sort instead.
The more general news-based article in Nature (http://www.nature.com/news/claims-of-earth-s-oldest-fossils-...) has several experts checking in with caveats.
In either case, what would it mean if it wasn't organic?
> The dating seems about right, said Abigail Allwood , a NASA
> astrobiologist who found the previous oldest fossil, from
> 3.48 billion years ago, in Australia. But Allwood said she is
> not completely convinced that what VanKranendonk's team found
> once was alive. She said the evidence wasn't conclusive enough
> that it was life and not a geologic quirk.
>
> "It would be nice to have more evidence, but in these rocks
> that's a lot to ask," Allwood said in an email.The dating seems about right, said Abigail Allwood, a NASA astrobiologist who found the previous oldest fossil, from 3.48 billion years ago, in Australia. But Allwood said she is not completely convinced that what VanKranendonk's team found once was alive. She said the evidence wasn't conclusive enough that it was life and not a geologic quirk.
"It would be nice to have more evidence, but in these rocks that's a lot to ask," Allwood said in an email.
In fact, even if it were a completely unbiased third-party opinion it would still be nice to have more than one, since as a lay-person I'm currently left with no idea how likely it is that this is in fact evidence of early life.
organic (comparative more organic, superlative most organic)
1. (biology) Pertaining to or derived from living organisms.