About 13 million years ago, a ground lazy wandered too close to the water’s edge, where a kaaiman lay waiting to strike. The attack likely happened in a flash, and ended with the caiman leaving nearly 50 tooth marks in the back leg of the lazy, a new study finds.
Most bite marks on the lazy bone’s are shallow pits and scabs, but the larger marks that pierce the tibia, better known as the shinbone, indicate that the caiman’s mouth closed over the leg’s. the lazy, causing terrible damage.
“There is no chance,” said lazy researcher Rodolfo Salas-Gismondi, a researcher at the BioGeoSciences Lab at Cayetano Heredia University in Lima, Peru. “The lazy tibia shows no sign of bone regeneration, which would be evidence of survival.”
Related: Photos: Old crocodile family wandered in the Amazon
The ground sloths (Pseudoprepotherium sp.) bone was found by the Napo River in northeastern Peru in 2004 by co-author of study François Pujos, a paleontologist specializing in the evolution of laziness at The Scientific Technological Center of the Argentine National Research Council (CCT). -CONICET).
It was not immediately clear what the 46 bite marks on the left tibia of the lazy had left. But in the years since Pujos discovered the bone, researchers have learned that the lakes and swamps in the early Amazon were “pletorous in crocodiles, with up to seven species living together at that time,” including a kick mouth crocodile with peg-like teeth, Salas-Gismondi told WordsSideKick in an email. (The crocodile order includes extinct and living crocodiles, alligators, caimans and gharials.)
Last year, Salas-Gismondi called back, Pujos approached him and asked, “Are we now ready to know who killed this groundbreaker?” The two began investigating the potential criminals. They excluded other predators living in the prehistoric swamps of Peru, including giant flightless birds (which had no teeth) and marsupials (whose teeth did not match the bite marks on the lazy bone). Instead, all the evidence blamed the giant caiman Purussaurus – a reed that can grow up to 10 meters long, making it the largest known non-marine predator after the extinction of non-avian dinosaurs, Says Salas-Gismondi.
“The teeth and anatomy of Purussaurus fits perfectly with the marks found in the tibia, “he said Purussaurus – probably a 13 meter long (4 m) youth based on the size of their tooth marks – probably the ground cover, although another scenario is also possible, he said.
“We can not deny that the marks were produced after death, by decomposing the carcass from the ground cloth,” notes Salas-Gismondi.
Crocodylians often leave these many bite marks on one bone, said Stephanie Drumheller-Horton, a paleontologist at the University of Tennessee in Knoxville who was not involved in the study. “I’ve done some work with modern crocodilians,” Drumheller-Horton told WordsSideKick.com. “They can really wear a bone. It’s not uncommon to find dozens and in some cases hundreds of individual tooth marks on one bone.”
Related: In photos: A jaguar takes down a caiman in Brazil
This is only the second fossil on record that shows evidence of a show Purussaurus Attack. The other is a shell from the water tortoise Podocnemis, which is on display at the Natural History Museum in Lima. That turtle pod held a 25-inch long (60 cm) bite mark on its shell. It “survived the attack,” Salas-Gismondi said, “but lost much of the carapace. [the upper shell] and the left hindquarters were amputated. We know that the turtle pod survives because it shows carapace bone regeneration. “
A turtle shell crackle would not have been a problem before Purussaurus, who lived during the Miocene period (23 million to 5 million years ago). As an adult, this caiman had a bite force estimated at 7 tons (6.3 metric tons), more than four times the strongest bite ever measured in living and extinct animals, according to previous research. (The saltwater crocodile Crocodylus porosus has a bite force of 1.6 tons, if 1.5 metric tons.)
“With this biting force, adult Purussaurus “individuals could include in their diet, whatever the size or severity,” Salas-Gismondi said. These animals had no parallel in the modern world. ”
The study was published online in the journal yesterday (August 26) Biology Letters.
Originally published on Live Science.
