Saber-toothed predators — such as the famous saber-toothed cat Smilodon fatalis — evolved multiple times across different mammal groups. Their unusual teeth were functionally optimal and highly effective at puncturing prey, according to new research led by University of Bristol paleontologists.
Graphic showing functional optimality drives repeated evolution of extreme saber-tooth forms. Image credit: Tahlia Pollock.
“Our study helps us better understand how extreme adaptations evolve – not just in saber-toothed predators but across nature,” said University of Bristol’s Dr. Tahlia Pollock.
“By combining biomechanics and evolutionary theory, we can uncover how natural selection shapes animals to perform specific tasks.”
Using 3D-printed steel tooth replicas in a series of biting experiments and advanced computer simulations, Dr. Pollock and colleagues analyzed the shape and performance of 95 different carnivorous mammal teeth, including 25 saber-toothed species.
They found that long, sharp blade-like teeth gave saber-tooth’s a real advantage as specialized weapons for capturing prey.
The findings help explain why saber-teeth evolved so many times — at least five independent times in mammals — and also provide a possible explanation for their eventual demise.
Their increasing specialization may have acted as an evolutionary ratchet, making them highly effective hunters — but also more vulnerable to extinction when ecosystems changed and their prey became scarce.
Another key finding challenges the traditional idea that saber-toothed predators fell into just two categories: dirk-toothed and scimitar-toothed.
Instead, the researchers uncovered a spectrum of saber-tooth shapes, from the long, curved teeth of Barbourofelis fricki to the straighter, more robust teeth of Dinofelis barlowi.
This supports a growing body of research suggesting a greater diversity of hunting strategies among these predators than previously thought.
The team now plans to expand their analysis to include all tooth types, aiming to uncover the biomechanical trade-offs that shaped the evolution of diverse dental structures across the animal kingdom.
“The findings not only deepen our understanding of saber-toothed predators but also have broader implications for evolutionary biology and biomechanics,” said Monash University’s Professor Alistair Evans.
“Insights from this research could even help inform bioinspired designs in engineering.”
The results appear today in the journal Current Biology.
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Tahlia Pollock et al. 2025. Functional optimality underpins the repeated evolution of the extreme ‘sabre-tooth’ morphology.’ Current Biology, in press;
