If you are refering to the Old Testament's claims of extraordinary 900+ year lifetimes (e.g. Methuselah, Adam, Noah),there is some dispute about tha accuracy of the Sumerian translations that led to those figures. See
http://en.wikipedia.org/wiki/Methuselah
You will find some fundamentalist speculation about longer ancient (biblical) life spans there. There are references to God's having reduced the maximum lifetint to 120 years after the Flood as some sort of punishment for human misbehavior.
Why in acient period people live more than the life span ???
3 answers
There is also a dispute about a watery dome that once covered the earth in Old Testament claims, preventing harmful sun rays from affecting our environment... that would dramatically raise the average death rate.
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