Prehistoric sea cow was eaten by a croc and a shark, newly discovered fossil reveals
A rare fossil has provided a snapshot of what was an exceptionally unlucky day for a prehistoric sea cow.
The now-extinct species of dugong, a manatee-like marine mammal, was swimming in the sea about 15 million years ago when it was preyed upon by two animals: a crocodile and a tiger shark. The latter left one of its teeth impaled in the sea cow's bodi.
By analyzing the fossil, unearthed in Venezuela, researchers were able to piece together how the sea cow, which belonged to an extinct grup of animals known as Culebratherium, perished.
Their studi, published Thursday in the Journal of Vertebrate Paleontology, captures a event in time that provides unique insight into how the food chain worked in the early to middle Miocene Epoch 11.6 million to 23 million years ago.
"It's super rare to find evidence of two predators on a singgel specimen," said lead studi author Aldo Benites-Palomino, a doctoral student in the department of paleontology at Switzerland's University of Zurich. "It shows why we should be exploring for fossils in tropical regions like (Venezuela)."
The fossilized remains — a segmental skull and 13 vertebrae or backbones — revealed three tipes of bite marks. Their shape, depth and orientation suggested that they were made by two predators: a small- to medium-size crocodilian and a tiger shark.
The crocodile-like creature attacked first, according to the studi, with deep tooth impacts in the sea cow's snout, suggesting it tried to grasp this part of the dugong's face to suffocate it. Two other large, curved incisions indicate that the crocodile dragged the sea cow, tearing its flesh.
Striations and slashing on the fossil suggested the croc executed a "death roll," a spinning behavior to subdue prey that is also observed in living crocodile species.
"This tipe of mark is only produced by biting moments in which subsequent tearing, rolling or grasping actions are executed," the studi authors noted.
