• Categories

  • Most Popular Questions

  • Recently Viewed Questions

  • Recent Answers

    How To Make a Digita… on What does a frequency of 100 H…
    Daigrepont on Can an earthquake cause air tu…
    Benedict on How did God come into exi…
    joshua on How does the human body g…
    Ian on How did God come into exi…
  • Recent Questions

  • Blog Stats

    • 2,227,323 hits
  • Visitors since 11-3-08

    counter create hit
  • Terms and Conditions

  • Warning

    We are doing maintenance on this site, so some posts may disappear for a short time. Sorry. Normal service will soon be resumed...
  • Pages

  • March 2008
    M T W T F S S
    « Feb   Apr »
  • Archives

  • Meta

  • Advertisements

Do jelly fish have a brain?

Do jelly fish have a brain?
Sam Bonurelli from Swansea (Age: 5-14)


12 Responses

  1. Cnidaria is the phylum to which “jellyfish” belong, phylum is the level of basic body organisation, such that all members of a phyla have similar body plans and are closer, in evolutionary terms to each other than animals in other phyla.
    It would depend on what you mean by a brain, they do not have a brain in the same fashion as vertebrates, but do have a nerve net with symetrical and asymetrical synapses (nerve conections). They show the best example of a diffuse nevous system. There are some nerve rings, circular concentrations of neverves within the medusae of these animals.

    Some animals show a very complex life cycle with alternating forms, such as Aurelia spp. with a sesile polyp which buds off medusa, (these are the more commonly seen “jellyfish”).
    The Cnidarians range from the small almost microscopic freshwater Hydra sp. to the more commonly known sea anemones and box jellyfish. They are also a component part of coral, which is a symbiotic mutualistic association of both an algae and a Cnidarian. Each coral “arm” contains many of these mutualistic “animals”.

  2. Dear Sam, jellyfish do not have brain as such. This is because their bodies are organized differently from ours. Most animals we encounter have what’s called bilateral – or two-sided – symmetry. They have a head end and a tail end. In the head end, they have a concentration of nerve cells – where these cells are complex, we call it a brain.

    Jellyfish do not have a head either. They’re “radially symmetric,” meaning they’re organized around a central axis. They’re just as likely to meet a new environment coming from any direction in the sea. Jellyfish have a loose network called a “nerve net” throughout their bodies. When any part of the nerve net is stimulated, an impulse travels across it in all directions.

  3. i think jelly fish do have brains 😀

  4. i beleive that jelly fish do not have a brain 😀 😀 😀

  5. yh me too my teacher said that jelly fish dont have brain!>.thats our lesson!>.:D:D

  6. I went to toronto zoo if u no where that is.. its in canada.. well they had jellyfish there and they had a thing talking about the jellyfish and No they have No brain and No bones

  7. If jellyfish don’t have brains, how can the box jellyfish actively hunt, and how do they process their surroundings if they had no brains? Surely they would have no functions like swimming or hunting.

  8. I think that jellyfish have consciousness but dont necessarily have (or need) brains. 🙂


    Just imagine for a minute that SETI is doing it all wrong – they are searching for intelligent life within a very narrow parameter/scope, such as that intelligence most likely couples with an organic body. But what if consciousness doesn’t have to accompany a biological lifeform? can intelligence exist as a plasma based lifeform? or perhaps something even less?

    that notion would imply that consciousness can exist outside of conventionally thought notion that a conscious lifeform has to have a brain in order to be intelligent.

    if we were to imagine for a second that consciousness is a process or mechanism that exists outside of organic material, then out of body experiences, spirits, channeling, telepathy etc are likely to be phenomena related to that notion – A notion that the brain doesnt generate consciousness, but acts as a radio receiver to intelligent signalling.

    Further following this idea – what if we were to conclude that intelligent consciousness (existing beside physicality) can be both local and ‘extra-terrestrial’ as to say – intelligence can travel from some other part of the universe or possibly from another dimension through the fabric of space/time and evetually interact with local ‘organic’ lifeforms.

    This idea would open up science, spirituality, religions and many other academic studies into new territory, perhaps it would even bring light to a lot of problems that has stumped academia for a long time.

    This would create a bridge between science in the fields of science, quantumn physics spiritual/religious teachings and others…

  9. While most jellyfish do not have a brain, it has been discovered that the Big Box Jellyfish has a small brain. This jellyfish also has eyes and sleeps at night.

  10. yeah jelly fish does not have a brain. I ve just been to the london aquarium and read it there.

  11. I’m no expert on marine life, but I think the entire nervous system serves as a brain.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: