Dinovember 2016, Day 7

Ornitholestes doesn't mind you noticing his baldness. 

Name: Ornitholestes hermanni
Meaning: [AMNH fossil preparator Adam] Hermann's bird robber
Time: Late Jurassic, c 154 million years ago
Place: Wyoming
Size: about 2 metres (6.6 feet) long and 15 kilograms (33 pounds)
Type of Dinosaur: tyrannoraptoran coelurosaur (birdlike predatory dinosaur)

Despite being one of the better-known coelurosaurs and small dinosaurs of the Jurassic Period, Ornitholestes is only known from one specimen, unearthed in 1900 at Bone Cabin Quarry in Wyoming - the site where the Diplodocus limbs and Dryosaurus skeleton on display at the Beneski Museum are from. In fact, Amherst College's very own bone bloodhound, Frederic Brewster Loomis, was a member of the team that excavated the single skeleton during his days working for the American Museum of Natural History.

The relationships of Ornitholestes have long been contentious, but it's definitely a bird-like coelurosaur, and thus would've had some sort of feathery covering. I've given this one a naked, bare-skinned head, both a nod to Gregory S Paul's 1988 Predatory Dinosaurs of the World restoration and just a look that I like to use a lot. The rest of the body is covered in loose feathers, with longer ones forming a sort of ruff at the base of the neck. And no, it doesn't have a little crest on its nose - that common element of Ornitholestes reconstructions was based on crushing of the skull during fossilisation.

Frederic Loomis Discovers Everything, Episode 1: Raiders of the Lost Continent

Around three million years ago, South America became connected to North America via the Isthmus of Panama, and an event called the Great American Biotic Interchange took place, where wildlife from South America moved north and vice versa. Prior to this, South America had been isolated from most of the rest of the world since the Cretaceous Period, and connected only to Antarctica until they separated about 30 million years ago, allowing little exchange of wildlife from other places in world. As such, South America was a 'lost continent,' a strange land cut off almost completely from the rest of the world, with its own array of unique organisms, the characters in their own isolated evolutionary story. It was into this strange world that the North American emigrants came some three million years ago, and it was into the fossil echoes of this world that a very different group of North Americans came in the early 20th century.

Some Patagonian fossils from the Cenozoic Era. They include notoungulates (top row
and left middle row) such as the sheep-sized digger Mesotherium (top centre), superficially
elephantine astrapotheres (lower jaw of Parastrapotherium, middle right), and the extant
xenarthrans (bottom row), including the flattened armour of an armadillo.
[photograph by the author]