But is that 6,000 tons or 13.5 billion tons?
I’ve asked many questions dealing with the topic, but I’ve never read a good answer concerning Adam and Eve - did they really exist?
We can tell from the current genetic diversity of the human population that the population of Homo sapiens has never been below 1,000 breeding pairs, with the probable figure nearer 10,000 breeding pairs. See Toba Catastrophe for references.
That figure says nothing about whether some or all of that population had souls. Souls neither fossilise and nor appear in DNA.
One possibility you might like to consider is to start with a population of unsouled upright apes, call then “huma” because they are not quite human yet. God puts a soul into two of them, Adam and Eve, (or puts a soul into one male, Adam, and clones a female, Eve, from him). Adding a soul does not change the original huma DNA at all. We now have a pair of humans, Adam and Eve, in a population of huma. Adam and Eve only mate with each other and have human children with souls. The children need to find mates outside their immediate family so they mate with some of the huma. This is possible because their DNA is compatible with huma DNA; the mating is open to the possibility of creating life. God gives a soul to all hybrid human/huma offspring so all the children with at least one human parent are also human, i.e. they have a soul. Because only the descendants of the initial pair mate with huma, all the children from such matings are descended from both Adam and Eve since they will have both as grandparents, great-grandparents etc.
Over time the number of humans increases and the number of huma declines until the huma are extinct.
In scientific terms we have a large interbreeding population, as shown by the current genetic diversity in humans. Theologically all humans are descended from that first ensouled pair.