Giant pandas have large molar teeth and strong jaw muscles for crushing tough bamboo.为咬碎坚韧的竹子，大熊猫有大的磨牙牙齿和强壮的颚肌肉。
Neuroscientists at the Universities of Michigan at Ann Arbor and Maryland injected saltwater into the jaw muscles of hea美国安娜堡密西根大学及马里兰大学的神经科学家，把盐水注射到年轻男性志愿者的下巴肌肉以引起疼痛。