Originally Posted: May 9, 2016
Don’t let those sharp teeth fool you, because this ancient hammerhead reptile had no appetite for meat.
The hammerhead’s most distinctive feature was its two menacing rows of teeth, with one group resembling needles and another group resembling chisels. That would normally hint that it was a carnivore, and probably one of the most fearsome sea creatures of its time. But the strangest thing about the animal is that it ate plants, with those rows of teeth serving a different purpose than what one may think.
A new study has detailed how Atopodentatus unicus (“uniquely strangely toothed”) existed in the middle Triassic era, millions of years before dinosaurs rose to prominence. Fossils of the hammerhead reptile were first spotted in 2014 in southern China, and based on scientists’ findings, the animal had lived about 242 million years ago, making it the earliest herbivorous marine reptile by only about eight million years. Not to mention, one of the strangest, according to the researchers.
“On a scale of weirdness, I think this is up there with the best,” said study lead Nicholas Fraser of the National Museums Scotland in Edinburgh. “It kind of reminds me of some of the Dr. Seuss creations.”
Aside from the unique teeth that gave the reptile its scientific name, A. unicus had a longer neck in proportion to its body, and a tiny head, also in relation to its overall size. Another key feature was the animal’s strong fore-limbs for swimming. Overall, A. unicus measured nine feet long from head to tail, making it about as large as a modern alligator.
Southern Methodist University paleontologist Louis Jacobs was not involved in the study, but he told Live Science about how A. unicus may have used its teeth. He said that the needle-like teeth may have also been used by the animal to collect plants, in a similar way to how baleen whale catches krill. The chisel teeth, on the other hand, may have helped the reptile scrape plants from the seafloor. Once A. unicus gathered its food, he added, it would “suck in a mouthful of water,” presumably to make the food easier to swallow down.
“Then, they squish the water out of their mouth, and those little teeth along the sides of the jaw and on the roof of the mouth strain out all of the plant bits,” Jacobs continued. “That’s an amazing way to feed. I’d like to do that myself.”
Fraser also shared his insights about A. unicus’ peculiarities, namely its being a plant-eater despite its sharp teeth, which was unusual for marine reptiles during the era. He believes this may have been due to a lack of plant diversity at the time.
“This fossil took us very much by surprise. However, this was a whole different world,” said Fraser. “So now we are beginning to accept this strange and wonderful environment that gave rise to very unfamiliar body forms.” READ MORE