National Fossil Day is Tomorrow! Do You Know the Paleontological Heritage of Your Region?

A hadrosaur skull similar to Saurolophus, the first dinosaur ever found in California

Tomorrow is National Fossil Day, which if anything, is of far greater interest than a holiday concerning an Italian explorer discovering a Caribbean island a few hundred years ago. One of the really exciting changes in our region is that our fossil heritage is being celebrated, pretty much for the first time. We finally have a museum with the room to adequately showcase the incredible paleontological history of the Great Valley of California. If you've read my blog at all, you'll know it's the Great Valley Museum at Modesto Junior College.

Two fossils here, but one of them isn't quite dead yet. The other is a Mosasaur

The Great Valley of California has a rich history of fossil discovery. Sediments were accumulating here in Jurassic and Cretaceous time, so dinosaurs and other reptiles have been discovered here, although not in concentrations like those of the continental interior. The first dinosaur ever discovered in California was found in our county. It was a Saurolophus, a variety of duck-billed dinosaur (the hadrosaurs). It was found by a teenager exploring Del Puerto Canyon in the 1930s.

Even more interesting, especially in light of a certain dinosaur movie last summer, are the Mosasaurs, large marine reptiles that were the terrors of the Cretaceous seas. One of them, Plotosaurus bennisoni, was discovered by the same kid who found the Saurolophus. It may have been 35 feet or longer in length.

Some fossils are more mundane, but they're exciting because I found them. Those would include these Jurassic wood fragments from the Sierra Nevada foothills. They were carried into the ocean by turbidity currents in the vicinity of the subduction zone that was once active here.

The most diverse and plentiful fossils are those of the creatures that grazed and hunted up and down our valley in Pleistocene time. The Fossil Discovery Center in the Madera area a few miles south of us has the best collection on display of these animals. The animals include the sometimes terrifying Short-faced Bear, Saber-tooth Cat, American Lion, and Dire Wolf. The grazers included a number of species of horse, camel and antelope, as well as mammoths and giant ground sloths. Many other smaller animals have been found in the quarry at Madera (which doubles as the sanitary waste disposal pit).

Few people in our county and region have had a venue in which they could learn about this fascinating fossil history, which is why the newly opened Great Valley Museum is such a wonderful opportunity. We have a full-sized skeleton of a Saber-tooth Cat, and a life-sized Mosasaur skull.

The newest exhibit highlights the research being done in Miocene sediments of the Mehrten Formation near Turlock Lake by the faculty and students of California State University, Stanislaus. Former MJC student Jake Biewer designed the current exhibit. The students are investigating some of the fossil sites where six-foot long "saber-toothed" salmon remains were found, along with tortoises the size of those found on the Galapagos Islands. Other exhibits are currently in the planning stages.

It's hard to describe how exciting it is to finally have a place to tell the story of the fascinating animals that lived here before us. The response from the children of our valley has been infectious. They love finding out that their home was once the home of that terrifying creature from the dinosaur movie, but also that they themselves could be the one who makes the next great discovery.

Have a great fossil day tomorrow! Learn something new about the place that you live!