It seems every couple of years...

It seems every couple of years we find another living fossil. In other words, there are creatures which are thought to have been extinct for tens of millions of years, and lo and behold we find some of them living. The latest is documented at http://www.cbc.ca/story/science/national/2006/05/19/crustacean-living-fossil.html

Got to love the last line of the report. "The biologists said their discovery shows that there are still places on Earth that haven't been explored yet." Well yes, but even more interesting would be hearing a biologist comment on what these living fossils mean for using rock strata to assign geological dates. Various creatures are used as index fossils. In other words, if some creature has been extinct for 60 million years, and we find some rock strata with those fossils, we know that the rock is about 60 million years old. But what happens when we find a living fossil? At that point the dating of the strata becomes uncertain. So the next time you are taking a tour of some geological formation and you are told it is tens of millions of years old, it may be time to raise some questions.