A question about original sin.

[twocompulsive]

There were only eight people on the Ark and they were
related to each other either by blood or by marriage. After
the first generation it would be impossible to procreate with
out recourse to incest. And would have known this was wrong
because of original sin. Nevertheless. By that scenario the entire
human race since then has been conceived through interbreeding
Admittedly this is reduced with successive generations but even so
According to a literal interpretation of Genesis the Earth was formed
in 4004 B C whilst the flood occurred in 2348 B C some 156 years later
Current population is 6.5 billion and so therefore has had 4359 years to
propagate. May in theory be possible but the average number of children
that each woman would have to bear is not realistic. Also the entire global
poulation other than Noah, his wife and their sons and wives was supposed
to have been wiped out. Yet the Egyptian Dynasty survived this. Records show
that it was in existence from 2980 B C to 663 B C. So therefore either the flood
was only regional and not global as referenced or else just never happened at all