Sabertooths’ massive canines required body changes that made movement awkward.
Evidence
Sabertooth teeth wouldn’t work without severe adjustments to jaw and skull shape, and to body posture. Over time, upper jaws became much shorter—even shorter than in other cats—producing powerful bite forces by bringing the canines ever closer to the hinge. Sabertooth jaws were thick, and the hinges could swing open to an unusually wide gape. Sabertooths had to pull their lower jaws all the way out of the way, as if releasing the bottom plate on a stapler, before they could sink their big teeth into prey. Finally, the shortened face and compressed skull tipped the head back, so the canines pointed forward during an attack. All of these modifications rendered these carnivores among the most deadly ever to live, but the postural and head-shape changes came at a steep cost. They made running—and basically all movement—cumbersome and awkward. — Emlen, Douglas J, Animal Weapons_ The Evolution of Battle, 79
Related
- Jaw shape trades off between bite force and bite speed (similarity 0.80)
- Sabertooth adaptations evolved independently in at least four mammal lineages. (similarity 0.80)
- Cat canines are piercing weapons vulnerable to side torque during hunts (similarity 0.80)
- Mammals split teeth into specialized tools for each task (similarity 0.79)
- Differentiated teeth only work with careful, deliberate chewing. (similarity 0.79)