It’s Shark Week so I figured this would be a good time to figure out if sharks have bones or not.
They do not.
Sharks actually use their gills to filter oxygen from the water. They are a special type of fish that’s made of up of all cartilage tissues like the stuff your ears and nose tip are made of. Similar to other fish like rays and skates. These cartilaginous skeletons are much much lighter than regular bone helping them float better.
They do tend to fossilize though because over time they build up calcium salts in which strengthens their skeleton.
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