The Pitt/Obama/ connection? It sounds d**n unfeasible to me- statisticians please answer!?

Question

It sounds d**n unfeasible to me- statisticians please answer- the odds of someone just happening to be related to nearly every major figure in American political history has got to be phenomenal! Robert E Lee, Winston Churchill, George Washington of course, and then throw in some pop stars for good measure. I doubt the validity of this greatly. Forget the Kenyan aspect, the U.S. is so improbable it doesn't even matter anymore.

What are the odds that this is real?

Answer 1

You must understand one thing: The few give birth to the many.

OF MITES AND MEN

Let's put this into perspective:

If you believe in evolution and a monophyletic [1] tree of life, then you believe that every living thing on earth came from a single little bug about a billion years ago. So really, you could say that Obama and Pitt are related to *you*, and everything is related to everything. However ...

OUT OF FEW, MANY

... We can't trace all the way back to that first little bug. But we can do some things with science. For example, by examining mitochondrial DNA (only passed on by mothers), scientists have determined that the native Americans had 6 founding mothers [2].

FAME MAKES GAIN

Knowing that some patriarch of old begat many modern descendants is rather unremarkable, as it really is just common sense.

But now, imagine that this patriarch was Leonardo DaVinci or George Washington. Your lineage suddenly becomes a whole lot more interesting. In fact, a fairly recent study actually shows that nearly 100 percent of people have royalty in their bloodline [3].

QUEENS AND KINGS: UNREMARKABLE THINGS

One explanation for the prevelance of royal blood is natural selection: Perhaps royalty possessed selective advantages - wealth, cleanliness, etc - that enabled those lines to endure while the commoners died off. And voila: They've made kings and queens of us all.

It may seem remarkable to us, but it makes no difference to the genetic and selection processes that are doing the same things they always have.

Answer 2

Just to take 4Father's point and embellish; Genographic - a Texan genetics laboratory - have found that all non-African people are directly related to a single man or woman from Kenya.

You did say "apart from the Kenya thing", but it is interesting to follow the path of most Americans through Europe. The decendants that entered Europe 35000years ago made up both Spanish, Irish and native UK populations. These in turn emigrated to the Americas.

Almost every person (90%) in the UK are related by only 24-25 generations max, excepting those who emigrated here reciently. Given that people living in the USA originated from an even smaller population who made their way over by ship, then the odds of Americans being related increases.

As for the Obama thing, I have no idea. It is probably another rumor.