| MadSci Network: General Biology |
Dear D.W.,
Yes, jellyfish are fairly dumb. Their nervous system is comprised
of a neural net. This net of nerves allows for very simple reflexes
to occur, such as those responsible for swimming and eating. Because of
the simple design of the jellyfish nervous system, it can not learn. While
it can respond to changes in its environment, these responses are reflexes
only.
However, it would be wrong to think of the unintelligent jellyfish
as primitive. Jellyfish are perfectly adapted to their lifestyle. They
simply don't need to think in order to accomplish everything that they need
to do. A brain wouldn't be very useful to a jellyfish. The success of
living
without a brain is apparent whenever you go to the ocean and see the
enormous number of these beautiful animals bobbing through the water.
To learn more about how jellyfish move, visit this Jellyfish page from Tufts University. This page
has a link to a neat video clip of a swimming jellyfish.
Thank you for your question!
John Carlson
MAD Invertebrate Scientist
Try the links in the MadSci Library for more information on General Biology.