Discoveries

April 07, 2023

Eyes on the Side

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South America’s Thylacosmilus atrox was a strange creature.

Living around five million years ago, the animal was a 220-pound marsupial sporting long and deadly canines – similar to those of other saber-toothed cats, such as the Smilodon fatalis.

Now, a research team found that the extinct mammal’s large teeth had forced it to adapt itself to a unique way of seeing for such a predator, CNN reported.

In their study, scientists explained that the T. atrox had eyes on the side of its head, resembling the format of cows or horses, while most predator species have forward-facing eyes and full 3D vision to help them chase after prey.

But the marsupial saber-tooth’s large canines precluded it from having eyes on the front of its face.

Researchers used 3D virtual reconstruction and scans to analyze the creature’s skull and compare it with that of other mammals, especially carnivores.

Their findings showed that its eye sockets were more vertically oriented than those of other comparable species, in order to achieve depth perception.

“One way to imagine it would be when you take a picture of a panoramic view with your cell phone,” explained lead author Charlène Gaillard.

Gaillard and her team suggested that Thylacosmilus’ vision showed that the animal was more of an ambush predator that waited for its prey, rather than pursuing it.

But the findings just add more questions about the species, for example, why was it the only animal to have large teeth that then required skull adaption, and how did it use other senses to hunt.

“We may view it as an anomaly because it doesn’t fit within our preconceived categories of what a proper mammalian carnivore should look like, but evolution makes its own rules,” noted co-author Analia M. Forasiepi.

This story originally appeared in the April 07, 2023 newsletter, Taking Out the Trash.