You and I can trace our respective family histories back to our great-grandparents -- maybe a bit further. But to track our lineage for 6,000 generations, we're going to need scientists.
That's where The Human Family Tree
comes in handy.
This illuminating National Geographic Channel special begins at a street fair in ethnically diverse Queens, N.Y., where representatives of The Genographic Project collected DNA swabs from random people to determine their origins. It ends with several dozen of them standing on a world map, demonstrating their ancestors' migratory patterns.
And in between, there's plenty of explaining how we're all descended from a small group of homo sapiens that lived in Africa 200,000 years ago, as well as how we might have ended up where we are.
It's an idea that seems self-evident: If you go back far enough, we're all related. But to see it laid out simply and neatly is exciting and fascinating. And proving its subtle sense of humor, The Human Family Tree
is narrated by Kevin Bacon, he of the "six degrees of separation" celebrity game. That's a nice piece of casting.
Bacon tells us that every man living today carries a chromosome that originated with one man in Africa 60,000 years ago, and every contemporary woman's DNA emanates from one woman who lived in Africa 150,000-200,000 years ago.
The reason for the difference in years, and how scientists have determined these figures, is not explained. But the two-hour program does an excellent job showing how the earliest human might have gone on to populate the globe, their decision to migrate caused perhaps by climate change or the need to find food and water.
It also offers what sound like reasonable explanations for some of our outward distinctions, such as skin tones. Races that lived in warm regions needed dark skin to be shielded from the sun; those in dark climates needed light skin to let in vitamin-rich sunlight.
The people we meet in Queens all seem to have high hopes that their DNA tests will yield important clues to their history. And for some -- like the African-American man who discovers his European ancestry -- the findings are surprising and noteworthy.
Others think the project might help bridge our racial and ethnic divides, which seems to be an extreme example of cockeyed optimism. "I'm hoping," one participant said, "that it will open people's eyes and make us more tolerant of each other."
Highly unlikely, but I guess it's pretty to think so.