Originally posted by MCA
The life found this deep (11Km) is among the most basic forms of life possible (single celled organisms, algae, slime mould etc.). It is unlikely that anything more complex could survive at even this relatively shallow depth, let alone within the mantle itself.
Of course mans understanding of the limitations/possibilties of life is not complete, so who's to say for sure 😕
The interesting thing about life is that there is not a definite definition of the very phenomenon 'life'. What is life really?, no one knows.
We define simply life as materia having DNA and have the possibility of reproducing.
Virus falls within even if it hs to have some help reproducing.
Prions fall outside the definition.
(What about my grandmother, she is no longer with us...?)
And what about mitocondriae? Not having DNA but have something else to reproduce itself with.
When life was young at Earth, the DNA-bound life was the only life that survived. We don't know anything more than that. Perhaps some other life did survived that have qualities that could, even still can, withstand the extreme preasures and temperatures that we find far below the surface, but again, we don't know anything about this. Even if we have a sample of this life perhaps we discard it as non-life, who knows.
Is this lack of a non-disputable definition of life pose a problem? Perhaps when we enter other planets with probes or even with astronauts - how can we discover that the planet already is habitated? With primitive bacteria or non-moving higher forms of life?
Just my thoughts...