A meter-long dromaesaurid from the Dinosaur Park Formation of Alberta

Albertonykus borealis, an alvarezsaur from the Horseshoe Canyon Formation of Alberta

I ran across the first skull in the basement of the American Museum of Natural History. I saw this beautiful ceratopsian frill, and and just out of curiosity I started wondering what species it was… and I realized, it didn’t fit anything I knew.

Titanoceratps, a giant horned dinosaur from the Fruitland-Kirtland Formation of New Mexico, and the possible ancestor of Triceratops

Judiceratops tigris, from the Late Cretaceous (Campanian) Judith River Formation of Montana (yes, not the most original of names) is the oldest known member of Chasmosaurinae, the long-frilled horned dinosaurs.

The phosphate mines of Morocco are the remains of an ancient sea, and produce vast numbers of shark teeth and mosasaur skeletons. At the time, sea levels were high, flooding North Africa, and the plains south of the Atlas Mountains were a shallow ocean, full of mosasaurs, elasmosaurs, marine turtles, and sharks. Giant seagoing pterosaurs wheeled overhead. It’s not the first place you’d search for a dinosaur, however, but this is where we found Chenanisaurus, a giant abelisaur.

A caenagnathid oviraptorosaur from the Campanian-aged Aguja Formation of Texas.

My little pony-sized duckbill dinosaur from the late Maastrichtian of Morocco. How did duckbills get from Europe to North Africa? They probably swam.

Vectiraptor greeni is a large dromaeosaurid from the Early Cretaceous (Barremian) Wessex Formation, of the Isle of Wight, England.

A little plant-eating dinosaur from the Early Cretaceous (Barremian) of the Isle of Wight. It’s only the second known species of Hypsilophodontidae, a family of dinosaurs only known from the Cretaceous of Europe.

Back in the 1980s, a huge tyrannosaur was unearthed in western New Mexico. Based on its size, it was widely assumed to be Tyrannosaurus rex. Closer study revealed otherwise.

When this little animal turned up in Morocco a couple years after Ajnabia, the first assumption was it would be a second example of that species. Instead, it turned out tobe something rather different.