THIS animal has no brain, heart, bones or eyes! |

How many times have you called someone heartless or brainless? Although referring to a human being can be offensive, in Zoology it is not! There is an animal that literally has no brain, heart, bonesor even eyes. If you’re wondering how such a creature could exist, we have news for you! This animal that has no brain, heart, bones and eyes is also beautiful. Jellyfish.
Jellyfish are one of the most fascinating creatures in the ocean. These planktonic marine members are invertebrates and belong to the phylum Cnidaria. Because they have a simple body structure, they lack many organs that complex life forms have, such as the brain, heart, bones and eyes! Well, that’s not all.
Older than dinosaurs

Jellyfish are ancient creatures that existed on Earth even before the first known dinosaurs. Fossil records date back more than 500 million years, making them about three times older than the first known dinosaurs. Scientists have found jellyfish fossils in Canada’s Burgess Shale that date back to the Cambrian geological period. The jellyfish lineage may be even older, as they rarely appear in fossil records because jellyfish are 95% water. Therefore, it is possible that jellyfish have existed in Earth’s oceans forever!
Jellyfish are not fish

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In this case, we cannot say ‘the name says it all’! Don’t be put off by the name, as Medusas are not fish! Yes, that’s right. Although they have a fish in their name, they are not fish. Fish are vertebrates, belonging to the phylum Chordata, that live in water and breathe through their gills. However, jellyfish are invertebrates, which means they have no backbone and absorb oxygen from the water through membranes.
95 percent water

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These fascinating creatures have unique characteristics, including the fact that their bodies are 95% water. The remaining 5% consists of structural proteins, muscles and nerve cells. They are all water, considering that the human body is made up of 60% water.
Since their bodies are mostly made up of water, they can easily float in the ocean. The gelatinous substance called mesoglea provides structural support and maintains its buoyancy.
No brain, heart, bones, or eyes

Beautiful and also deadly

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Jellyfish come in all shapes and sizes. There are large, colorful jellyfish known as true jellyfish, box jellyfish, which are venomous, lurking jellyfish that do not float or swim but live attached to rocks or seaweed, and hydrozoans, which are small.
Jellyfish use their stings to defend themselves from predators and to attack smaller creatures. Box jellies are highly advanced among jellyfish. They are considered among the deadliest in the world, as they contain toxins that attack the heart, nervous system and skin cells. On the other hand, some jellyfish also have bioluminescent properties and glow in the dark.