New discovery sheds light on famous saber-toothed tiger’s mysterious family life

New research indicates that the teenage offspring of the menacing saber-toothed predator, Smilodon fatalis, were more mother’s pups than independent warriors.

A new study by scientists at the Royal Ontario Museum (ROM) and the University of Toronto, published on January 7, 2021 in iScience¸ documents a family group of saber-toothed cats whose remains were discovered in present-day Ecuador. By studying the fossils, collected for the ROM in the early 1960s, scientists were able to show that while the oversized cats of the Ice Age grew quickly enough, they also seemed to stay with their mothers longer than some other large cats before. to forge theirs. path.

“This study began as a simple description of unpublished fossils,” says Ashley Reynolds, a graduate student of the Royal Ontario Museum who led the study while completing her doctorate. research in ecology and evolutionary biology at the University of Toronto. “But when we noticed that the two lower jaws we were working on shared a type of tooth that is only found in about five percent of Smilodon fatalis population, we knew the work was about to get much more interesting. “

Encouraged by this new discovery, the researchers dug deeper and found that they were probably looking for three related individuals: an adult and two “adolescent” cats. Additionally, they were able to determine that the youngest cats were at least two years old when they died, an age at which some living big cats, such as tigers, are already independent.

To support this conclusion, the team investigated the preservation and formation of the Ecuadorian site (a study area called taphonomy), based on historical collection records and the suite of clues from the fossil bones themselves. .

Historically, Smilodon specimens that were largely collected from “predator trap” deposits, such as the famous La Brea tar pits in Los Angeles, California. But the Ecuador deposit, which formed on a former coastal plain, is likely derived from a catastrophic event of mass death. This means that, unlike the “traps”, all the fossils in the deposit died at the same time. As this preserves a snapshot of an ecosystem, fossils like these can provide new and unique information about the behavior of extinct species.

“The social lives of these iconic predators have been mysterious, in part because their concentration in tar seeps leaves a lot of room for interpretation,” says Dr Kevin Seymour, assistant curator of vertebrate paleontology at ROM and co -author of this study, “This historic assemblage of Ecuadorian saber-cat fossils formed in a different way, which allowed us to determine that the two juveniles likely lived and died together – and were so probably brothers and sisters “

The fossils were collected in Coralito, Ecuador, in 1961 by A. Gordon Edmund, curator of vertebrate paleontology at ROM from 1954 to 1990, and Roy R. Lemon, who was curator of invertebrate paleontology from 1957 to 1969. Together, Edmund and Lemon collected tons of tar-soaked sediment which was then prepared at the ROM.

“These world-famous collections made 60 years ago have been studied for years, but one measure of their importance is that they continue to generate new knowledge about the lives of these extinct animals,” says Dr. David Evans, President of Temerty in Vertebrate Paleontology at the Royal Ontario Museum and Reynolds Thesis Director.

Provided by the Royal Ontario Museum