> I think that the boundary case is that we at least have a common ancestral single cellular life-form. It is possible to imagine several different single cell

> I think that the boundary case is that we at least have a common ancestral single cellular life-form. It is possible to imagine several different single cells being our ancestore. If we pretend a lightning strike in the ancestor primordial DNA soup sparked life, then it could have sparked life in millions of cells with a single lightning bolt. There could even have been several different puddles of DNA soup.