The Morrison Formation of western North America is my favorite geological / paleontological formation to study. Within these rock layers, which are dated to the late Jurassic Period from approximately 157 to 147 million years ago, are found the fossils… Read More ›
reptile
Saurosuchus
Saurosuchus was a 20-foot pseudosuchian (a distant ancestor of crocodiles) which lived in Argentina during the middle Triassic Period about 230 million years ago. It was the largest carnivorous animal in its environment in terms of both length and weight,… Read More ›
Fruitachampsa, the crocodile-bear-cat of the Morrison Formation
Meet the Jurassic Period’s analog of the common house cat. This is Fruitachampsa callisoni, a prehistoric reptile which inhabited western North America during the late Jurassic Period. However, this was not a dinosaur. In fact, Fruitachampsa was a distant relative… Read More ›
Pantosaurus
Hello everyone. Several years ago, I wrote a short article for Prehistoric Times magazine about the Sundance Sea. This was a shallow saltwater sea which covered much of central North America during the middle to late Jurassic Period. One of… Read More ›
Baptanodon
This is Baptanodon, an ichthyosaur which lived during the late Jurassic Period about 160-155 million years ago. During this time, the central part of North America was covered with a body of saltwater known as the Sundance Sea, and Baptanodon… Read More ›
Stegosaurus
Introduction There are over a thousand species of dinosaurs that are known to science today. Kids, it seems, are more disposed to remember these names than adults, and I have encountered several examples of children trying to impress people by… Read More ›
Champsosaurus: The Croc-Lizard of the Cretaceous
When most people hear the words “aquatic reptile”, they usually think of two things: turtles and crocodilians. Some clever people might mention sea snakes, and others might mention marine iguanas. Those who are keen on impressing you may bring up… Read More ›
Allosaurus, revised
Greetings, all. For those who regularly visit this website, you will know that this post has been a long time coming. Years ago, I mentioned that I was planning on re-doing my Allosaurus drawing so that it would be more… Read More ›
Some Morrison Formation Sauropods: Apatosaurus, Barosaurus, and Diplodocus
Hello everyone. Here are some simple sketches of three Late Jurassic sauropod dinosaurs from the Morrison Formation of western North America: Apatosaurus, Barosaurus, and Diplodocus. All three of these sauropods are members of the family Diplodocidae, which includes the eponymous… Read More ›
Evidence of Therizinosaurs in North America during the Late Cretaceous Period
Introduction For many years, paleontologists have known about the presence of therizinosaurs (formerly classified as segnosaurs) in Asia, especially within what’s now Mongolia and China. However, Asia and North America were linked during a considerable portion of the Cretaceous Period,… Read More ›
