Our Crazy, Mixed Up Family

If you ever want to calculate how many ancestors you’ve had, say, in the past five hundred years, start off with your two parents. Each of them had two parents, so multiply two times two. And each of them had two parents, so multiply that number times two. Then continue: two times two times two times two — twenty-one times. That’s twenty-one generations, and that takes you back five to six hundred years. Your final calculation will tell you that over two million ancestors have been swirling around in your gene pool. Each one of us has had millions of unknown characters dancing in our DNA, waltzing with our chromosomes, fiddling with our genetic makeup. And every one of those two million or more characters are part of our ancestry — our crazy, mixed-up family if you will.

Confronting this reality can have a rather humbling effect on us. But running through this mixture of humanity and leading straight to us is a common thread.…