Prehistoric ­Detective Work

       Saur, from the Greek, tells you it’s some kind of lizard, likely a dinosaur, as that’s this suffix’s common use. There’s little else familiar about this Plesiosaur — except its connection to Calvert Marine Museum.

     First, the introduction: Plesiosaurs are stout-bodied, long-necked lizards, from the age of dinosaurs that propelled themselves through their oceanic environment using four flippers.

     Then the connection: It’s not the ancient ocean that is now our Chesapeake. Rather it’s the Museum’s man on such ancient environments, paleontologist Dr. Stephen Godfrey. With an international team of paleontologists from Chile, Argentina and the United States, Godfrey found a plesiosaur from long ago Antarctica that was rather like a whale.

     Instead of a marine predator, like other plesiosaurs, this saur was a strainer feeder like baleen whales, creatures that did live in the Miocene Chesapeake.

     Teeth were the clue that tipped off the team led by F. Robin O’Keefe a globally recognized scientist specializing in Mesozoic marine reptiles. The tiny teeth in the fossil’s lower jaw pointed the wrong way. Nor did they meet tip to tip as in all other plesiosaurs, instead lying together in a battery that acted in straining food particles from the water. This feeding style is unknown in other marine reptiles.

     It may, the scientists concluded, be an evolution “linked to changes in ocean circulation brought on by the southward movement of Antarctica during the Late Cretaceous period.”

     Visitors to Calvert Marine Museum can see what this pivotal plesiosaur likely looked like.