Flat-headed Dino Discovered in Romania (!)

Evolutionary biologists have something called the “island rule,” which posits that organisms that evolve on islands will, over time, become smaller than their mainland counterparts. A new dwarf dinosaur species discovered in western Romania – which long, long ago featured tropical islands – supports the theory.

Transylvanosaurus platycephalus ("flat-headed reptile from Transylvania") lived 70 million years ago and grew to about six and a half feet. The relatively little guy was a vegetarian who walked on two legs.

By the late Cretaceous period, flowering plants had arrived and the first flying reptiles were leaving the ground. While landlocked today, the Haţeg Basin of western was home to at least one flat-headed reptile which left a few bones behind, including part of its skull.

Science hasn’t settled why animals tend to shrink, evolutionary speaking, on islands. It’s possible that with no predators, there are no natural-selection pressures that induce larger organisms. Perhaps there is simply less food variety on islands, which could stunt growth.

Relatives of T. platycephalus have been found in modern-day France, a part of which was also a separate, isolated island at the time. The little guy got around.

The new discovery is reported in the Journal of Vertebrate Paleontology.

Illustration by: Peter Nickolaus