Human Life Span & Evolution

Has it not been that human life span has been gradually increasing? Has gradually increased?The Bible gives life span in hundreds of years, but how can that be? With evolution at work, shouldn't life span generally increase over a period of time?Consider, Person A has a long life span, and person B has a short one. The life span of both people is determined by their DNA--it either determines their ability to survive longer, or in some other way the length of life they will be able to live. Because person A has a longer life span, he/she will be able to produce more children (all of which themselves have the genetics for a longer life span). Person B doesn't live as long, and so he/she can only produce a smaller number of children, who unfortunately for them all have the short-life-span genetics.So, eventually the person A lineage not only is able to outnumber, but outlast the person B lineage. Person B's lineage will dry and fade away. We go from having an average life span of A+B (long + short), to having one that is only A (long).If what's-his-face was living back in the land of God until the ripe old age of 400 something, then why am I not expected to keep kicking until the year 2956?Does any of this make sense? Is there any explanation a Bible-believer could give me as to why my time is limited to only a few dozen years? And please, oh God, do not tell me it's the Fall.This is all my hypothesis, and I have no solid evidence for it yet.JonEdited by Invictus, : added part about not having evidenceEdited by Invictus, : removed comment to admins

Thread moved here from the Proposed New Topics forum.

YEs, the average human lifespan has been increasing for the last bunch of years, basically due to the increase of better health care. However,
even in roman times, there were a number of individuals from the high classes of soceity that had the better environment to live, and therefore lived into their 80's and 90's.. so the potential has not increased.As for the biblical stories.. well, one item about aging, skeletons show signs of their age, and it is possible to determine how old someone was when they died. There is no physcial evidence that the life span as reported in the bible is anything but a story.

Okay, so my fanciful theory is flat-out wrong, and from the start I've believed the stories to be just that: stories. However, I've never seen a reason given by a Bible-believer to explain why people suddenly started living far shorter lives.Trék

Just so we understand where I'm coming from, I'm a Christian but I believe that the Bible although true is not to be read as a scientific text or a newspaper. It does not affect my faith whether individuals named in the Bible lived 400 years or not.It does seem to me that one of the characteristics of evolutionary theory is that over time our gene code has evolved to produce what we are today. (I've no background in biology so if I use wrong terminology feel free to correct me.) Apparently genetic study has gone so far now as to have made some discoveries about the ageing process within our DNA. Isn't it possible that as we evolved there have been genetic changes that have caused to age at a different rate than our distant ancestors?Also another thought is that what they referred to as years were actually lunar cycles.None of this is scientific or even theological but just my own ruminations on the question.

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Everybody is entitled to my opinion.

gen 5.6: And Seth lived an hundred and five years, and begat EnosThat looks a bit young for lunar cycles.

Yeah but Seth was a horny little devil.Actually the ages claimed in the early Genesis myths are pretty much toned down. If you look at even older documents, like the Epic of Gilgamesh the lifespans are considerably longer than anything claimed in the Bible.These are classic mythos, tales bigger than life designed to entertain and to teach.

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Aslan is not a Tame Lion

I've seen several such explanations, typically along the lines of "their DNA was more nearly perfect before the Flud" or "the Vapor Canopy blocked ultraviolet light and there was more oxygen in the antediluvian atmosphere." Pure BS and adhoccery, of course, and YEC's never actually say "antediluvian" - too many syllables.

Ramoss, I think then as now the primary improvement pushing longer life spans was simply a matter of sanitation and clean water supply. Some very basic principles of human waste disposal and safe water distribution allow the opportunity to reach a genetically-limited age--even today millions die from the diseases that are rampant without rational sanitation practices. Dysentery ravages infants and children in the less developed world.Invictus, while there have always been some children born to older parents, the percentage is small. Selection doesn't get much opportunity to operate on genes for longevity because prime reproductive years are youthful years. Also, the probability of defective genes increases in aging germ cell lines, e.g., Downs' syndrome among the infants of older mothers, and, recently, a correlation established between having an older father and being at risk for schizophrenia.The diseases of advancing age--atherosclerosis, cancer, dementia, etc.--have not been strongly selected against because they have little or no impact on reproductive fitness.Some theorists have argued that elders who survive longer provide an advantaqe to their group via culture/memes to explain why we live past our prime reproductive years. The onset of menopause rather than child-bearing unto death is sometimes cited as an example.It occurs to me that the near universal tendency for old dominant males to obtain young mates might play some part in conserving longer life spans, but I think I'll say no more about that.Edited by Omnivorous, : Typo. I'm old, I can't help it.

That is very likely... that and a better food supply.

Maybe they lived longer because of no food additives, no un-natural fertilzers, no air pollution.... you get my drift.

Well, we live longer, on the average, because of food additives like preservatives, fertilizers, and pesticides. Not too many folks in the industrial world starve any more - largely due to the increased food supply that things like these make possible.And nobody has ever lived as long as 150 years, except in myth.Edited by Coragyps, : slow thought processes

GDR writes

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Apparently genetic study has gone so far now as to have made some discoveries about the ageing process within our DNA.

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There's no such thing as aging process within our DNA. Aging is caused by DNA damage due to imperfection in mitosis.

I have to concur with Omnivorous for the most part. Medicine has advanced like building blocks, as we build off anothers technology. Technology begets technology, and it has better served us in understanding how diseases occur and how to combat them. As well, our understanding of trauma and internal medicine has helped us increase the the odds of survivng that surely would have killed a man in the distant past.For instance, I had appendecitus in 2000. It dawned on me that while I could be considered very healthy, especially when I was much more conditioned at that time, that anything could still happen. Healthy or not, who knows what tragedy might befall us. I considered that had I lived in Biblical times, I could have easily died from spilt toxins from a ruptured appendix. But, I'm still here.At the same time, there are many accounts of people living well into their 80's and 90's in more ancient times, as somebody pointed out. Perhaps they had a kick ass immune system, got lucky, prayed to God feverishly, lived in an area where disease was not as prevelant, or all of the above. Who knows? I don't think there is way to quantify that information just because there are so many variables.I noticed that people mentioned the Biblical account of people living to the ripe old age of 900 years (Methuselah 969 yrs) in the antediluvian world. In the postdiluvium world, those numbers decreased to 400, 300, 200, 150, and so on; all the way down until 70 was considered a ripe old age. The trend seems to be a downward spiral since God's judgement, relatively speaking. Is it true? Perhaps. I believe it to be true, however, this is based off of my faith. The only corroborating evidence we have comes from other antiquities, such as the 'Epic of Gilgamesh,' as somebody has pointed out. As to the reasons for why they lived so long, and then dwindled so quickly, there are alot of theories. Some people think that a vapor canopy (similar to the ozone layer) comprised the upper-stratosphere as the 'firmament' spoken about in Genesis. This canopy, they theorize, helped hyper-oxygenate the earth and aided in decreasing the amount of potentially harmful UV light. Others have claimed that it may have to do with genetic purity, and the steady loss of information makes every following offspring 'less-pure.' Some people think it has to do with the Fall of man, and that its attributed spiritually. Some have attributed it to God allowing for long lives to help mankind proliferate in the beginning to 'fill the earth and subdue it,' and as more humans live on the earth, that those ages start to decline. (Kind of like God's population control). No one really knows. The Bible is a bit ambiguous as to the reason.As to whether it happened at all is a matter of speculation and interpretation, I suppose. Make your inferences.

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“Always be ready to give a defense to
everyone who asks you a reason for the
hope that is in you.” -1st Peter 3:15

I'm certainly not arguing the point, but I thought I'd read that biologists had thought they had found the gene or genes that caused ageing and that possibly they would be able to curtail the ageing process.