It no longer counts as the world's smallest dinosaur, but Compsognathus still holds an important place as one of the earliest theropods in the fossil record. Here are 10 facts you may (or may not) have known about this tiny carnivore..
1. Compsognathus was discovered in the mid-19th century...
Most of the dinosaurs identified in the first half of the 19th century were massive plant-eaters like Iguanodon, which is why the discovery of the tiny, meat-eating Compsognathus--in Germany in the 1850's--caused such a stir. However, Compsognathus wasn't the first theropod dinosaur ever to be named; that honor belongs to the still-controversial Megalosaurus.
2. ...in the same fossil beds that yielded Archaeopteryx.
For years after its discovery, Compsognathus was indelibly linked with the feathered proto-bird Archaeopteryx, the only remotely similar creature to be discovered in Germany's Solnhofen fossil beds. So strong was the association that it wasn't until 1896 that Compsognathus was recognized as a true dinosaur, by the famous paleontologist Othniel C. Marsh.
3. Compsognathus may have been the biggest dinosaur of its habitat...
The numerous, exquisitely preserved fossils of Solnhofen provide a detailed snapshot of a late Jurassic (150 million years ago) ecosystem. Depending on how you classify Archaeopteryx, Compsognathus is the only true dinosaur to be retrieved from these sediments, which were more extensively populated by pterosaurs and prehistoric fish.
4. ...but it was still only the size of a turkey.
The first identified fossil of Compsognathus belonged to an individual weighing only a few pounds. What most people don't know is that a second Compsognathus specimen, discovered in 1972 in France, was substantially bigger (perhaps as much as 10 pounds). It's now believed that this second fossil was an adult, while the Solnhofen specimen belonged to a smaller juvenile.
5. For a century, Compsognathus was believed to be the smallest dinosaur.
Although it's often, and inaccurately, presented as the current record-holder, it has been quite a few years since Compsognathus has been considered the "world's smallest dinosaur." That honor now belongs to the accurately named Microraptor, a tiny, feathered, four-winged "dino-bird" that only weighed three or four pounds soaking wet, and that represented a side branch in theropod evolution.
6. Compsognathus wasn't far removed from the earliest dinosaurs.
About 80 million years separated Compsognathus from the earliest dinosaurs--small theropods like Herrerasaurus and Eoraptor that populated late Triassic South America. The gulf in time looms larger than the gulf in anatomy, though: in most respects, including its small size and slender legs, Compsognathus was very similar in appearance to these "basal" dinosaurs.
7. Compsognathus may (or may not) have congregated in packs.
Despite that reference to "Compies" in Jurassic Park, there's no compelling evidence that Compsognathus traveled the plains of western Europe in packs, much less that it hunted cooperatively to bring down larger dinosaurs. On the other hand, though, this kind of social behavior wouldn't be an unusual adaptation for such a small, vulnerable creature!
8. There's no evidence that Compsognathus had feathers.
One of the odd things about Compsognathus--especially in light of its close affiliation with Archaeopteryx--is that its fossils bear absolutely no imprint of primitive feathers. Rather, Compsognathus appears to have sported classically reptilian skin, which makes it the exception rather than the rule among the small theropods of its Jurassic ecosystem.
9. Compsognathus subsisted on smaller reptiles...
Since Compsognathus was such a small dinsoaur, it's a reasonable bet that it didn't prey on comparably smal theropods. Rather, analysis of the fossilized stomach contents of some Compsognathus specimens shows that this dinosaur preyed on smaller, non-dinosaurian lizards, though it probably wasn't above munching on the occasional fish or already-deceased pterosaur.
10. ...which it captured with its grasping, three-fingered hands.
Like most theropods of the Triassic and Jurassic periods, Compsognathus relied on its speed and agility to run down prey--which it then snatched up with its relatively dexterous, three-fingered hands. Since this dinosaur needed to maintain its balance during high-speed chases, it also possessed a long tail, which acted as a counterweight to the front portion of its body.