Palaeontologists have found a rock in Dorset that has got them very excited, but they cannot agree over what it shows.
"One thing we're sure of," said Chris Tal, head of the British Geological survey, "is that the rock is four hundred million years old. Give or take a few million."
The rock has what appears to be a fossil in it, but not all palaeontologists can even agree on that.
"I think it's just a rock," said Sandy Stone, palaeontologist chair of King's College. "It doesn't even look like a fossil."
The group of palaeontologists from Manchester Metropolitan University who found the rock insist that it is the earliest example of a jawed fish found to date. "It is the branching point between jawed fish and sharks," said Julian Dates, the leader of the expedition. "As everybody knows, jawed fish went onto become amphibians and then us."
Katie Boundary, of the Cambridge Archaeological Survey, disagrees. "It's definitely a fossil, but not of a jawed fish, it looks nothing like a jawed fish. It's a late bacterial colony that indicates the world was undergoing a previously undiscovered dry spell with most of the water locked up at the poles. This is revolutionary stuff. I cannot believe it's come to light. This vindicates all of my published papers. It's the missing bit of evidence."
The only thing everybody can agree on, is that this lump of rock from Poole will provide a sea change in the way that we view ancient history.