Really? Let's see a natural rock formation precisely in the shape of a human being or other animal.
There are of course natural rocks capturing living forms: fossils. And a huge number of them are completely obviously from ancient life. Nobody goes to a museum and sees a T Rex skeleton and thinks, Hey, that might actually be rocks that had nothing to do with life.
The real issue - not well stated in the article - appears to be regarding single celled life, or at least small-cell-count ancient organisms. Then there's ambiguity in interpretation because of overlap with inorganic possibilities.
There are of course natural rocks capturing living forms: fossils. And a huge number of them are completely obviously from ancient life. Nobody goes to a museum and sees a T Rex skeleton and thinks, Hey, that might actually be rocks that had nothing to do with life.
The real issue - not well stated in the article - appears to be regarding single celled life, or at least small-cell-count ancient organisms. Then there's ambiguity in interpretation because of overlap with inorganic possibilities.