The Mysterious Extinction of an Ancient Predator
by Aissata Bah, age 10
Although saber-tooth tigers have been extinct for around 12,000 years, long-held beliefs that they died out due to hunger, climate change, and human hunting are turning out to be incorrect.
In an attempt to find the real reason, researchers have studied the fossil teeth of 15 saber-tooth tigers and 15 American lions that were recovered at the La Brea tar pits in Los Angeles. These animal fossils ranged from about 11,500 to 35,000 years in age.
Scientists used a dental microwear analyzer to examine these fossils. The tool was developed by anthropologist Peter Ungar at the University of Arkansas. It generates three-dimensional pictures of the surface of a tooth. Eating red meat creates a parallel set of small scratches, but biting bones leaves larger and deeper pits. The investigation found a pattern of wear on the saber-tooth tiger teeth, and it looks similar to the pattern on the present-day African lion teeth.
The analysis of the aged fossils and additional new ones suggests that the pattern of wear has not changed over time. None had extreme microwear, like living hyenas that consume carcasses, including bones. This shows that there was enough prey for the carnivores, and the animals were not biting their prey to the bone.
“Tooth wear patterns suggest that these cats were not desperately consuming entire carcasses, as was expected, and instead seemed to be living the 'good life' during the late Pleistocene, at least up until the very end," Larisa DeSantis, a vertebrate paleontologist at Vanderbilt University, said.
Researchers in the past who have studied the teeth of the American lion, saber-tooth tiger, dire wolves, and coyotes from La Brea discovered that the broken teeth are three times the regular amount of contemporary predators, hinting that these species were having trouble finding prey and were immediately devouring whole carcasses. This led scientists to think that climate change and humans made the big predators’ life tough.
Instead, Desantis and her partners argue that this high rate of damage seen in teeth may be more likely the result of capturing the prey instead of eating the carcasses.
They argue that ancient carnivore teeth were bigger, and large teeth break more easily than smaller teeth. So, larger carnivores have a bigger chance of breaking their teeth when they try to take down a bigger prey, rather than from eating it.
"We expected extinct carnivores to show evidence for extreme bone processing, based on the high number of broken teeth determined from prior research. Finding the complete opposite pattern was shocking!" DeSantis said.
Scientists still don't know what caused the extinction of the saber toothed tiger. They are currently looking for clues by researching other extinct animals in the La Brea tar pits. For example, they are trying to find out why the giant short-faced bear is extinct but not the mountain lion.