The Big Dinosaur Podcast

Episode 57 is all about Compsognathus, a small dinosaur whose name means “elegant jaw.”

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In this episode, we discuss:

• The dinosaur of the day: Compsognathus
• Name means “pretty jaw” or “elegant,” “refined” or “dainty”
• Only one valid species, Compsagnathus longipes
• Lived in the late Jurassic
• Fossils found in Germany (1850s) and France more than 100 years later
• Specimen found in France was larger than the German one, and thought to be a separate species, C. corallestris (no longer valid)
• Virginia Morell renamed Sinosauropteryx prima to Compsognathus prima in 1997, but most people don’t accept this
• German specimen discovered in 1859 in Bavaria, same area Archaeopteryx fossils have been found
• Johann A. Wagner named Compsognathus longipes and described it in 1861
• German specimen is 35 in (89 cm) long
• French specimen found in 1971 by Louis Ghirardi. Alain Bidar described it as a new species, C. corallestris, but John Ostrom, Jean-Guy Michard and other paleontologists have classified it since as C. longipes (Quimby said the smaller German specimen was a juvenile). The National Museum of Natural History in Paris acquired the French Composagnathus in 1983
• French specimen is 49 in (125 cm) long
• Largest Compsagnathus (France) weighed between 1.8 and 7.7 lb (0.83 and 3.5 kg), estimate
• Teeth found in Portugal may also be Compsagnathus
• In 1998, Jens Zinke said that 49 teeth found in Portugal belonged to Compsognathus (not identifcal to C. longipes since it has serrations on the front teeth, and Compsognathus front teeth were unserrated, but has general similarities)
• German specimen had only two digits on each forelimb (so scientists thought it only had two digits), but the French specimen had three digits (the German specimen’s third digit just wasn’t fossilized)
• One paleontologist thought Compsognathus had webbed forefeet that looked like flippers. And the 1975 book The Evolution and Ecology of the Dinosaurs shows Compsognathus as amphibious. However, Ostrom said this wasn’t possible, since the French and German specimens were the same except for their sizes
• Marsh thought the lizards found in the German Compsognathus‘ belly was an embryo (1881) but Franz Nopcsa in 1903 said it was a lizard. Ostrom identified it as the lizard Bavarisaurus (fast and agile runner), which shows Compsognathus was fast (able to outrun the lizard) and had good vision. The lizard is in one piece, so Compsognathus swallowed it whole
• Scientists used to think they had found Compsognathus eggs, since they were found close by, but now they think they’re note Compy eggs (since they were not found inside Compsognathus, eggs were 10 mm long), and its relative Sinosauropteryx had preserved eggs in oviducts that were much larger, 36 mm long)
• Thomas Huxley compared Compsognathus and Archaeopteryx in 1868; John Ostrom redescribed it in 1978 (became one of the best known small theropods)
• Compsognathus and Archaeopteryx have similar shapes and proportions (two Archaeopteryx specimens were mislabelled as Compsognathus for a while). Now other dinosaurs are seen as more closely related to brids: Deinonychus, Oviraptor, Segnosaurus
• Compsognathus is similiar to some of the earliest dinosaurs, like the small theropods Herrerasaurus and Eoraptor (bipedal archosaur from the Triassic, 80 million years before Compsognathus); similar in appearance and behavior
• Small, bipedal, carnivorous theropod
• Grew up to the size of a turkey, though has been described as chicken-sized (due to a specimen found in Germany, which is now thought to be a juvenile)
• Used to be considered the smallest known dinosaur (smaller ones now include Caenagnathasia, Microraptor, Parvicursor)
• But may have also been the dominant dinosaur in its area
• Where Compsognathus was found (France and Germany) had lagoons, beaches, and coral reefs, and used to be islands
• Other animals in the area at the time included Archaeopteryx, and pterosaurs, fish, mollusks, crustaceans (no other dinosaurs found, which may mean Compsognathus was the top predator)
• Had small, sharp teeth (ate small vertebrates and possibly insects); front teeth on the premaxilla were unserrated and back teeth were recurved and flattened (teeth used to identify Compsagnathus and close relatives)
• Small lizard remains found in both Compsagnathus bellies (one of the few dinosaurs where we know for sure what they ate)
• May have also eaten small mammals (based on well preserved fossils of its relative, Sinosauropteryx)
• No evidence that Compies traveled in backs or hunted to take down larger animals, though it wouldn’t be unusual for a small creature to have that kind of social behavior
• Had a narrow skull with long snout; had large eyes
• Had a long neck, so it could quickly move its head side to side, and could also put its head in undergrowth and pull out prey that was hiding
• Forelimbs were smaller than hindlimbs, had three digits with claws
• Had long hind legs and long tails, used for balance
• Feet were digitigrade (balanced on its toes), so its main foot bones extended the length of its leg and increased its stride (helped it be faster)
• One study in 2007 estimated that Compsognathus could run up to 40 mph, based on measurements and hypothetical weights of a few carnivorous dinosaurs
• May have had feather-like structures on body (though none have been found)
• Some relatives, like Sinosauropteryx and Sinocalliopteryx, had simple feathers preserved (covered the body like fur)
• One relative, Juravenator starki, had a patch of fossilized skin with mainly scales (some evidence of simple feathers too), but that may mean not all dinosaurs in their group were covered in feathers
• Can see a cast of Compsagnathus at the Oxford University Museum of Natural History (based on fossils Joseph Oberndorfer acquired in Bavaria in 1859)
• Compsognathus appears in many children’s dinosaur books, because for a long time they were the only small dinosaur known
• Compsognathus is also in the movies The Lost World, Jurassic Park III
• In the Lost World, a character misindentifies a Compsognathus as Compsognathus triassicus (combing Compsognathus longipes with Procompsognathus triassicus, a distantly related carnivore in the Jurassic Park novels
• Called Compys in Jurassic lego game
• In the game Ark, there are wild and domesticated Compys. In packs they become aggressive and attack. Alone they can be a pet. They are also curious when it comes to humans
• Family is Compsognathidae (small dinosaurs from the late Jurassic and early Cretaceous that lived in what is now China, Europe, and South America)
• Compsognathus was the only member of Compsognathidae for a long time, but now includes Aristosuchus, Huaxiagnathus, Mirischia, Sinosauropteryx
• Skin impressions of Juravenator, Sinosauropteryx and Sinocalliopteryx show evidence of primitive feathers covering their bodies. Juravenator and Compsognathus have evidence of scales on the tail or hind legs.
• Scientists debate on where Compsognathidae lies in the coelurosaur group. Some say it’s the most basal of coelurosaurs, and others say it’s part of Maniraptora
• Fun fact: The Chicxulub impactor was either a comet or asteroid that was between 10 and 15km or 6 to 9 miles in diameter. Mars has a moon called Deimos (the Greek God personifying terror – and the same root as “dinos” in dinosaur) that is right in the middle of that range.