Two hundred million years ago our planet Earth bared little resemblance to the world we know today. Even separate continents did not exist. There was one land mass, called Pangaea. The fossils found here in the Watchung Reservation date back to the Jurassic and Triassic periods.
The fish are Semionotus and lived both lakes and the ocean. They had a deep body and small mouth, with teeth adapted chiefly to biting and scraping. As you can see from the display, fossils are very fragile and break easily, even when removed by a trained scientist, as this one was, by Dr. Paul Olsen, in 1976.
Because fossils are so fragile, that is why we always ask visitors to the Reservation to “Take only pictures and leave only footprints.”
In addition to the fish, there is a fossil of a fern and the footprint of a theropod dinosaur. Scientists believe this dinosaur was shaped like a female wild turkey. It stood five feet at the hip and had a long boney tail, explained Olsen, who discovered the Reservation fossils. He found the dinosaur track on his 21st birthday.
The theropod dinosaur, which was feathered like a bird, was a carnivore, a meat eater, and probably bore a strong resemblance to Coelophysis or Dilophosaurus, but did not have that scary frill of the Dilophosaurus fictitiously featured in the movie, “Jurassic Park.”
The dinosaur’s footprint may be a little confusing at first glance-it puzzled trained scientists.
To understand it, imagine a walk on the beach, where you used to seeing your footprints make impressions in the sand. But imagine you are a mole crab living in the sand and a foot just descended above you. The sand underneath the foot would all be moving towards you.
That is the moment in time captured by this fossil, explained Olsen. And don’t worry if you don’t get it at first. “I didn’t understand it for 20 years,” said Olsen, who is a professor of Earth and Environmental Sciences at Columbia University. These types of fossils are “penetrative tracks” that actually captured the movement of animals as they stepped through the mud.
At the time the dinosaur left that imprint, there was a layer of soupy silt on top of the mud that forever captured the shape of the dinosaur’s lower leg and foot.
“These are important because they record the whole motion and that was something we did not understand at all,” Olsen said