[RightWhale]

With the [I assume] differences in genetic or DNA structure of the various hominids, how can it be that modern humans all have the same basic DNA structure, only the genes showing varibility, if our ancestors interbred with different species?

[blam]

A quick answer. I don't think we have a good or complete understanding of DNA. I've read to many DNA reports/results that heurestically do not seem correct.