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 ›
reptile
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 ›
Coelurus again
Coelurus is one of my favorite theropod dinosaurs, and has been since I was young. It’s not as well-known as other Jurassic theropods like Allosaurus, Ceratosaurus, and Ornitholestes, partly because it is only known from fragmentary evidence. Yet I’m always… Read More ›
Hallopus
This is Hallopus victor, a 3-foot long reptile that lived in the Morrison Formation of western North America during the late Jurassic Period approximately 150 million years ago. Hallopus belonged to a group of reptiles called the “sphenosuchians” a group… Read More ›
Camptosaurus
This is Camptosaurus dispar, a 20 foot long plant-eating dinosaur from the Morrison Formation of western North America during the late Jurassic Period. In most paleo-art, it seems that the only purpose in life for this unfortunate animal is to… Read More ›
Macelognathus
This is Macelognathus vagans. This animal lived in the Morrison Formation of western North America during the late Jurassic Period approximately 150 million years ago. Macelognathus belongs to a group of animals called the “sphenosuchians”, which is a group that’s… Read More ›
Dryosaurus
NOTE: This article was originally posted on April 8, 2020. It was substantially updated on December 14, 2022. This is Dryosaurus, a 10 foot long plant-eating ornithopod dinosaur from the Late Jurassic Morrison Formation of western North America, and possibly… Read More ›
Ceratosaurus Osteoderms: A Revised Perspective
Ceratosaurus is an iconic dinosaur due to numerous physical attributes that distinguish it from other theropod species: the horn on the end of its nose, the massive teeth, the tiny hands with the four fingers, the wide tail, etc. However,… Read More ›
Haplocanthosaurus: An Enigmatic Sauropod from the Late Jurassic Period
Introduction The sauropods are the definitive image of the dinosaur. Almost always, whenever one hears the word “dinosaur”, the image of the long-necked long-tailed four-legged behemoth is what immediately springs to mind. The sauropods were the dominant land herbivores during… Read More ›
Othnielia
Othnielia rex was a small ornithopod dinosaur found in the Morrison Formation, a famous geological formation spanning a large chunk of the western United States which is dated to the late Jurassic Period, 157-147 million years ago. It is here… Read More ›