Europasaurus

Europasaurus
Europasaurus (Andrey Atuchin).

Name:

Europasaurus (Greek for "European lizard"); pronounced your-ROPE-ah-SORE-us

Habitat:

Plains of western Europe

Historical Period:

Late Jurassic (155-150 million years ago)

Size and Weight:

About 10 feet long and 1,000-2,000 pounds

Diet:

Plants

Distinguishing Characteristics:

Unusually small size for a sauropod; quadrupedal posture; ridge on snout

 

About Europasaurus

Just as not all sauropods had long necks (witness the short-necked Brachytrachelopan), not all sauropods were the size of houses, either.

When its numerous fossils were unearthed in Germany a few years ago, paleontologists were astonished to learn that the late Jurassic Europasaurus wasn't much bigger than a large ox--only about 10 feet long and one ton, max. This may seem large compared to a 200-pound human, but it's positively stunted compared to classic sauropods like Apatosaurus and Diplodocus, which weighed in the neighborhood of 25 to 50 tons and were almost as long as a football field.

Why was Europasaurus so small? We may never know for sure, but an analysis of Europasaurus' bones shows that this dinosaur grew more slowly than other sauropods--which accounts for its small size, but also means that an unusually long-lived Europasaurus might have reached a respectable height (though it would still have seemed puny standing next to a full-grown Brachiosaurus). Since it's clear that Europasaurus evolved from larger sauropod ancestors, the most likely explanation of its small size was an evolutionary adaptation to the limited resources of its ecosystem--perhaps a remote island cut off from the European mainland.

This type of "insular dwarfism" has been observed not only in other dinosaurs, but also extant mammals and birds.