The oldest trees on Earth

Key Facts

"It's remarkable to sit there and have your hand on one of those trees and know that it was growing when the Pyramids were built," said Bunn.
Matt Salzer, a dendrochronologist at the University of Arizona's Laboratory of Tree Ring Research, said, "Each annual tree ring is like a time capsule of the environment for that year from which it was formed.
"If you're trying to look at people in the past through time, tree rings give you a way to do it in a way that makes sense in a human life scale," said University of Arizona professor Charlotte Pearson.
"It blew my mind that trees on the other side of the world could possibly be used to date this thing to within a single year," she said.