They need them to breathe through. Dolphins, being mammals, have to inhale air and hold their breath underwater.
To breathe.
To breathe
Dolphins have blow holes, not blow horns. The blow hole allows the dolphin to inhale and exhale air. The blow hole is analogous to a nostril in other mammals.
Dolphins (and whales, etc) breath through the blow holes on their head.
Both dolphins and whales have blowholes because they do not have noses to breathe but a hole to breathe when they reach the surface of the water.Therefore,this is an adaptation for both animals.
Only one, located on the top of its head. Dolphins cannot breathe through their mouth, only their blow holes.
I believe the main reason for dolphins being warm-blooded is because of the blow holes they have. This allows to go up to the surface of the water and breathe the air all others on land inhale.
Because they are whales and they need to breath.
They are mammals so they breathe in air like us. When they are swimming, its easier to breathe through their blow hole then their mouth so they dont have to completely come up out of the water to take in a breath
No whale sharks don't have blow holes they have gills like other sharks
dolphins
Blow hole