Yuto Moronuki on Instagram: "So apparently sharks do yawn… but why? The reason remain unclear and scientists are still trying to solve this mystery. Here are the functions currently proposed in scientific literature regarding “yawning” (or wide-gape buccal opening) in fishes including sharks. Note most research refers to yawning as gaping, jaw-stretching, or buccal cavity expansion, not the mammalian analogue of yawning. 1. Respiratory Ventilation Adjustment This is one of the most widely accept