NARRATOR: Now with the assurance of DNA insight, the family tree of living flowering plants has largely been written. The old family tree was now in for a major pruning. Roses were found to be closely related to squash, strawberries to marijuana, this meat-eating pitcher plant to China's famous rhododendrons. For centuries water lilies were thought to be nearly twins with the lotus—no longer.
MARK CHASE: This, believe it or not, is the closest living relative of the lotus. This is the London plane tree or sycamore. As you can see, this is not a little water plant, this is a big tree.
ANDREW DARRAGH (Horticulturist, Kew Gardens): …driving me nuts!
NARRATOR: Andy Darragh is in charge of tending to a garden at Kew that is organized by the old family tree of plants, it's called the Order Beds. He's got the somewhat overwhelming job of trying to bring order to the new order.
ANDY DARRAGH: We're in this weird limbo period. I'm trying to not only do a job of gardening, mowing, edging, and weeding constantly, but I've also got to keep myself up to date. And I've also got to try and understand plant science and botany. I wish it was simpler, but it's not.
NARRATOR: Perhaps the biggest surprise from the DNA evidence is that when all the number crunching was done, one plant showed up at the very bottom of the family tree of living flowering plants, Amborella, the oldest branch of the family tree—a plant so rare that it is only found in the remote Pacific island nation of New Caledonia. So is Amborella the world's oldest flowering plant? Not the fossil Archaefructus that Sun Ge discovered? Not necessarily.
PETER CRANE: The molecular evidence allows us to really understand living plants in enormous detail. What it doesn't allow us to do is to account for all the diversity that's extinct.
It’s another example of viewing the data according to the theory rather than viewing the theory according to the data.