Before dinosaurs walked on Earth, that is, more than 210 million years ago and when the supercontinent Pangea had just started breaking apart and giving birth to the continents as we know them today, our planet was inhabited by little dog sized dinosaurs, as has been revealed by the fossil of a tooth dug out by the researchers only recently.
These dinosaurs which were almost as large as dogs, hid from predators at the top of the food chain: reptilian predators called phytosaurs and rauisuchids and scientists now have reasons to believe that these predators may have interacted with each other far more often than was previously thought.
Not very long time back, it was believed that there was not much interaction between the two top predators since one was primarily a land animal while the other one was a water creature but the new tooth fossil has changed this perception drastically.
“Phytosaurs were thought to be dominant aquatic predators because of their large size and similarity to modern crocodylians, but we were able to provide the first direct evidence they targeted both aquatic and large terrestrial prey,” said Michelle Stocker, one of the researchers.
According to Science World Report, this was the outcome of the discovery of a phytosaur tooth lodged in the thigh bone of a rauisuchid that must have been at least 25 long and four feet high at the hip when alive. This tooth presents evidence that these creatures interacted with each other along the food web. Finding teeth embedded inside a fossil is rare. Very rare.
“This is the first time it’s been identified among phytosaurs, and it gives us a smoking gun for interpreting this set of bite marks.”
Drumheller teamed up with Michelle Stocker and Sterling Nesbitt, both of Virginia Tech, to carefully examine the rare fossil. To make sure that they did not cause any damage to the fossil, they had to recreate it with 3-D printers. If not for the tooth, they may have never known who the rauisuchid’s attacker was.
“It was remarkable we were able to reconstruct a part of an ancient food web from over 210 million years ago from a few shallow marks and a tooth in a bone,” said Sterling Nesbitt, another one of the researchers. “It goes to show how careful observation can lead to important discoveries even when you’re not seeking those answers.” The findings were published in the journal Naturwissenchaften.