21Rare sponge
The world's largest known sponge was discovered off the coast of Hawaii. The animal is an unidentified genus of sponge with a bluish-white color and brain-like appearance, around the size of a minivan.
22Pistol shrimp
Alpheidae a.k.a the pistol shrimp is one of the loudest animals in the sea. The quick snaps it makes with its specialized claw creates a cavitation bubble moving at 60 miles per hour. When the bubble collapses it reaches temperatures of over 7,700°C and is 218 decibels loud, which is strong enough to kill small fish, and even create a tiny flash of light.
23Immortal jellyfish
There is a jellyfish that undergoes a process called transdifferentiation. Instead of dying, they can reverse its life cycle, earning the name the Immortal Jellyfish - the only known animal to do this.
