scientificphilosopher:

Fish Using Jellyfish as Shelter

Jellyfish serve as a habitat to many ocean creatures… Jellyfish play a critical role in the lives of different marine creatures. While they are used as a direct food source for many, some use them as shelter (juvenile fish), some as a means of travelling from A to B and some have a combined interest of travelling while snacking on the microscopic parasites attached to the Jellyfish.

These symbiotic relationships are very intricate and are being investigated by scientists. 

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chalkandwater:

A small Japanese puffer fish is the creator of one of the most spectacular animal-made structures. To impress the female puffer fish, the male labors 24 hours a day for a week to create a pattern in the sand. If the female finds his work satisfactory, she allows him to fertilize her eggs. She then lays them in the middle of the circle, leaving the male to guard the eggs alone.

Life Story (2014)

unexplained-events:

Mimic Octopus

This sea creature can mimic the behaviors and various shapes of different animals it sees. They are highly intelligent and use their ability to camouflage and avoid predators. It is so intelligent that it will actually mimic a sea creature that its predators is afraid of. For example, scientists observed that when the octopus was attacked by territorial damselfishes, it mimicked the banded sea snake, a known predator of damselfishes.

It can mimic sea creatures like the sole fish, lion fish, sea snakes, frog fish and more.

SOURCE