After their fall from the garden of Eden,
humans typically lived to be several hundred of years old, and
very near 10 times are current lifespan. The oldest recorded
age in the Bible was Methuselah's who is said to have lived 969
years (Gen 5:27). Noah himself was older than 500 when he gave
birth to his three sons, and six hundred years old at the time
of the flood (Gen5:32). In addition to destroying all life on
earth, it is believed that another intended effect of the flood
was to reduce the maximum human life expectancy to 120 years
(Genesis6:3).
Following the flood, lifespans declined
to what we have today, but developed over the course of several
generations. For a period of time, people were able to live to
similarly old ages following the flood as they did before. Noah
lived another three hundred and fifty years, and didn't die until
he was nine hundred and fifty years old (Gen9:28-29).
The changes in the earth's ecosystem caused
by the flood probably forced human's to adapt in this way. It
is probably a result of the relatively harsh post-flood ecosystem
that we now live as long as we do. However, as the effect was
not immediate, but declined gradually, it was probably the result
of classic-evolution following
the flood. Humans have become genetically disposed to the modern
lifetime expectations which is 1/10th its original, or to a maximum
of 120 years.
Gen 6:3-7 Then the LORD said, "My
spirit shall not abide in man for ever, for he is flesh, but
his days shall be a hundred and twenty years." The Nephilim
were on the earth in those days, and also afterward, when the
sons of God came in to the daughters of men, and they bore children
to them. These were the mighty men that were of old, the men
of renown. The LORD saw that the wickedness of man was great
in the earth, and that every imagination of the thoughts of his
heart was only evil continually. And the LORD was sorry that
he had made man on the earth, and it grieved him to his heart.
So the LORD said, "I will blot out man whom I have created
from the face of the ground, man and beast and creeping things
and birds of the air, for I am sorry that I have made them."