Blue whale

Blue whale.Balaenoptera musculus.This whale has been gathering food deep within the water column and reaches the surface with the throat pleats still distended, forming an enormous pouch. The whale is laying on its side, a pectoral flipper visible above. Within a few moments the whale will right itself up, expell the water, swallow the food, take several breaths, and dive again.Gulf of California (Sea of Cortez), Mexico. (Photo by: Francois Gohier/Universal Images Group via Getty Images)