What animal has no brain? Almost all animals have a brain, but there are a few exceptions. There is one organism that has no brain or nervous tissue of any kind: the sponge. Sponges are simple animals, surviving on the sea floor by taking nutrients into their porous bodies.
What animal never dies? To date, there’s only one species that has been called ‘biologically immortal’: the jellyfish Turritopsis dohrnii. These small, transparent animals hang out in oceans around the world and can turn back time by reverting to an earlier stage of their life cycle.
What animal has a third eye? When it comes to the pineal eye, for example, the animal with the most pronounced “third eye” is actually the tuatara, an ancient lizard endemic to New Zealand.
What animal has no blood? Flatworms, nematodes, and cnidarians (jellyfish, sea anemones, and corals) do not have a circulatory system and thus do not have blood. Their body cavity has no lining or fluid within it. They obtain nutrients and oxygen directly from the water that they live in.