“A few centuries IS insignificant, if you posit a 100,000 year plus time scale, unless those contractions were extraordinarily severe.”
Again, you are making a raft load of totally wrong assumptions. You assume the birth and survival rate from the average was applicable to the early periods, when they certainly were not. You wrongly assume the pandemics did not affect enough people in the short term of a few centuries or less to have a significant enough effect to preclude a millenia eqrlier exponential population explosion like the one that occurred in the last two or three centuries.
You ignore how reducing a population to zero in the space of only one year has the effect of extinction despite the average population growth which erroneously assumes a continued population growth into the future years of a populaton that no longer exists at all. Likewise, a population that has been severely pruned to 70 perent or 10 percent of its former numbers is going to take considerably longer to return to its former numbers, especially if and when conditions do not permit an annual increase in numbers for most of the following centuries or a number of millenia.
This is especially true in the prehistorical period when natural catastrophes cause all but one of the hominids to become extinct, and the surviving hominid, Homo sapien sapiens was nearly made extinct as well. It doesn’t do much good to have 120,000 years of bare existence and miniscule increases in population when something like an asteroid impact comes along and reduces your population to barely more than a thousand individuals who must eke out a barely sustainable existence for survival for millenia to come as the environmental conditions recover.
“You assume the birth and survival rate from the average was applicable to the early periods, when they certainly were not.”
No, I haven’t assumed that. If you’re going to try to claim I did, then back it up and quote me.
“You wrongly assume the pandemics did not affect enough people in the short term of a few centuries or less to have a significant enough effect to preclude a millenia eqrlier exponential population explosion like the one that occurred in the last two or three centuries.’
Again, quote where I made that claim.
“You ignore how reducing a population to zero in the space of only one year has the effect of extinction despite the average population growth which erroneously assumes a continued population growth into the future years of a populaton that no longer exists at all.”
No, you ignore the words I wrote, specifically: “unless those contractions were extraordinarily severe”. An extinction event is by definition an extraordinarily severe contraction.
“It doesn’t do much good to have 120,000 years of bare existence and miniscule increases in population when something like an asteroid impact comes along and reduces your population to barely more than a thousand individuals who must eke out a barely sustainable existence for survival for millenia to come as the environmental conditions recover.”
It seems like you are probably ignoring the fact that such events kick in a survival response in all sexually reproductive organisms, and a change in their breeding patterns. After any such event, there will be a population growth explosion, so you can’t simply say the graph was reset to zero at all these points and then continued as usual. That doesn’t get you the nearly flat-line growth that you need.