Of course. Noah was married and so were his 3 sons. Noah's grandsons had NO other Humans to marry so they married and produced children with the sons of God (prehistoric people) who numbered some 1 Million 11k years ago. Cain did the SAME thing on Adam's Earth. Cain (His kind) married a prehistoric woman (Their kind) and passed Adam's superior intelligence all over the first world, the world that then was. Genesis 6:1-4 This was repeated by Noah's grandsons on the present Earth.
I'm sorry - none of that is a genetic mechanism.
You see, traits are governed by genes (and the interactions of those genes with the environment - but you still have to have the genes). In humans, when a sperm and egg fuse, the zygote gets 1 set of genes from the father, 1 set from the mother. A gene in the sperm's genome has a counterpart gene in the egg's, and they are not always the same version of the gene. These different versions are called alleles. Some alleles 'overrule' their counterpart (dominant -> recessive). Some alleles sort of work together, etc. Regardless, we get 2 alleles per gene in a zygote (barring mutations/duplications, etc.).
The people on the ark produced inbred offspring, and had no source of new alleles (other than mutation). All 4 breeding pairs were from the same area, and so likely had very little allelic diversity to start with.
And yet, in a mere 4500 years, we end up with billions of people with varied 'ethnicities' and dare I say 'races', from the tall, thin, very dark Bantu, to the short, fairer-skinned Inuit to the tall pale and blond Nordic groups, to those of Asian characteristics, etc. - all in 4500 years.
So my question was what is the genetic mechanism whereby the new alleles required to produce the extant level of diversity were produced so quickly; how were they so quickly segregated into distinct populations? If there were somehow present in the ark folk, how were the "un-used" alleles kept around?
That sort of thing.
