Harriet made it into the Guiness Book of World Records as the oldest living animal. Hatched on the Galapagos Islands in 1830, brought overseas by Darwin (who named her Harry - sexing turtles was not one of his strengths) she eventually ended up in the Australia Zoo.
Our common ancestor with the turtle lived around 310 million years ago, or 170-million-great-grandparents. Most of the coal we use today came from the giant club moss trees that populated the swamps at the time. For the record, I'm not spouting this off the top of my head - I wouldn't want anyone to think I was smart (an erroneous conclusion if there ever was one). I'm getting this info from Richard Dawkins' great book, The Ancestor's Tale. Harriet would want you to check it out.
If you're interested in purchasing the picture, click here.
(Back on track - another sale. I think the subject helped. Thanks, Harriet.)