糖心视频

Saber-toothed predators鈥攂est known from the infamous Smilodon鈥攅volved multiple times across different mammal groups. A study titled "Functional optimality underpins the repeated evolution of the extreme 'saber-tooth' morphology" in Current Biology reveals why: these teeth were 'functionally optimal' and highly effective at puncturing prey.

The study, led by scientists at the University of Bristol in collaboration with Monash University, shows that long, sharp blade-like teeth gave saber-teeth 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鈥攂ut also more vulnerable to extinction when ecosystems changed and their prey became scarce.

The team set out to test whether saber-tooth shape was an optimal balance between the two competing needs: sharp and slender enough to effectively puncture prey and blunt and robust enough to resist breaking.

Using 3D-printed steel tooth replicas in a series of biting experiments and advanced computer simulations, they analyzed the shape and performance of 95 different carnivorous mammal teeth, including 25 saber-toothed species.

Lead author Dr. Tahlia Pollock, part of the Paleobiology Research Group in Bristol's School of Earth Sciences, explains, "Our study helps us better understand how extreme adaptations evolve鈥攏ot just in saber-toothed predators, but across nature.

"By combining biomechanics and evolutionary theory, we can uncover how natural selection shapes animals to perform specific tasks."

Another key finding challenges the traditional idea that saber-toothed predators fell into just two categories: "dirk-toothed" and "scimitar-toothed."

Instead, the research 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.

Looking ahead, the team 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," added Professor Alistair Evans, from the School of Biological Sciences at Monash University.

"Insights from this research could even help inform bioinspired designs in engineering."