The jaguar's bite force allows it to pierce the carapaces of the yellow-spotted Amazon river turtle and the yellow-footed tortoise.[77][78] It employs an unusual killing method: it bites mammalian prey directly through the skull between the ears to deliver a fatal bite to the brain.[79] It kills capybara by piercing its canine teeth through the temporal bones of its skull, breaking its zygomatic arch and mandible and penetrating its brain, often through the ears.[80]It has been hypothesized to be an adaptation to cracking open turtle shells; armored reptiles may have formed an abundant prey base for the jaguar following the late Pleistocene extinctions.[77] However, this is disputed, as even in areas where jaguars prey on reptiles, they are still taken relatively infrequently compared to mammals in spite of their greater abundance.[73]