Can a jellyfish communicate

Answer 1

They can't see. They are more or less like plants. They are blind so they operate by touch (i.e. if anything touches there tentacles, they release toxins).They have privative eyes. Unlike our eyes they can't see exact shapes. They can however detect differences in colors. They can then react to a given situation based upon those colors. Correction: They don't have eyes. They use stimuli in their tentacles to sense things.

Answer 2

True jellyfish have no eyes. Jellyfish can detect light and dark, which they do with the ocelli. The number of these ocelli can vary from very few to several hundred, often with one at the base of every tentacle. These photosensitive organs are nothing like vertebrate eyes. There is no lens nor retina, so no images can be formed, and hence they can't distinguish distance and shape. There are also no rods & cones, so they do not detect color in the usual sense. The pigments in the ocelli might be more sensitive to certain colors. It is true that some species have no ocelli.

In the case of Polyorchis penicillatus, for example, if you shine a light on them, then suddenly douse it, they will immediately begin to swim. A reaction to the change in light level. Jellies will start swimming as it gets dark (avoiding a predator), and hence avoid getting tangled. The mechanism is that the change in light level causes some kind of neurotransmitter release which in turn opens the gates which allow the pacemaker part of the animal's 'brain' (nerve ring) to start driving the swimming muscles.

Box jellies, or Cubozoans, however, (not true jellies) have developed rather complicated eyes. Some of their eyes have lenses and retinas, and studies have shown that they use them to navigate obstacles. They also have demonstrated behaviors that also indicate an ability to track prey. Much more research is needed to clarify these issues, however.

Answer 3

With eyes, called ocelli; most of them can see shapes, distances, colours and movements.

Answer 4

No, they can't even hear or see . But many have light sensitive organs around the margins of their bodies that detect objects.

Answer 5

I know that the moon jellyfish is

Answer 6

Yes.

Answer 7

Yes

Answer 8

No.