According to Moses people during the first 2000 + years after the formation of The Adam lived nearly a thousand years. Imagine that if you can, Methuselah lived 969 years, the longest recorded life span in a flesh body. It was the Creator repulsed by the activities of His children that brought forth the flood. Only Noah and his family of the descendants of the Adam, had not mixed with the fallen angels.
I know that for the all ethnic peoples we find upon this earth today that one of two things had to have occurred. Noah took two of every flesh, including all ethnicities, or else that flood only covered the portion of this earth wherein the descendants of the Adam that had polluted their bloodline to Christ. Now there is some evolutionary biology to study.
It was just prior to the flood that God shortened the flesh life span to 120 years.
I do not dispute that 'modern medicine' has in many cases extended the life span of many people. But eventually all flesh dies and returns to the dust from which it came....and their soul/spirit, good - bad- or indifferent returns to the Maker that sent it to be judged.
Oh and that term "survival of the fittest' has become so politicized it means whatever the entity handing out dollars or demanding dollars, decides it means. Our founders stated that there are unalienable rights that come only from the Creator, 'life, liberty, and the pursuit of happiness... whereas liberals claim they can do things better, playing 'god' decide who they will fund to survive.
Do you also believe the earth is flat? And that the stars above are lights affixed to the inner surface of a dark shell? Six thousand years ago, people lived less than 30 years on average, and there is no objective evidence to show otherwise.
You have yet to give any reason why one should believe the description of the earth and life found in a metaphorical moral lesson is literal truth, while the reality seen and described by countless people over the course of millenia should not be believed. Despite your claims of not caring about the physical world, your desperate clutching to a metaphor while fervently denying the nature of reality says that you care, a lot.
What I surmise about a lot of literal creationists is that they actually believe that if the earth was not created exactly as described in Genesis, there can be no basis for faith. So the fact that there is no evidence of a sudden, recent creation is very upsetting. They'd be so much happier if they could learn a few lessons from the millions of Christians who are perfectly okay with the fact that Genesis is a metaphor.