The question is, "whose science is correct?"
http://www.reasons.org/human-origins/adam-and-eveWhile one group says, "Do the math," and you can't come up with fewer than 10,000 human beings existing at any point in history or pre-history, another says "Do the math," and you can not only have all chromosomes from one original male and female, but they couldn't have existed more than 20,000 years ago.