Question

As far as I know, a jellyfish has no brain or other abode for the soul. So where does a jellyfish get the ability to plan its life? Is this proof that mentality does not require a brain, or are these instincts of a higher order than what we are familiar with?!
 
Lisa Bateson, one of the editors of the famous jellyfish studies, says that the research examined hormonal responses of various creatures alongside their behavior. Besides jellyfish and other mollusk-like fish, bees also took part. The findings indicate that the behavior of these creatures is not a meaningless reflex, but rather a fairly organized and systematic response that can be mapped into a behavioral pattern. “Jellyfish are not just some spineless creature carrying venom inside it,” says Bateson. “They have a complex visual system that helps them navigate through swamps and the sea. Their nervous system is concentrated mainly in the brain.”
So yes, the new study discovered that jellyfish have planning ability, and they also have eyes (a matrix of 24, to be precise) and a nervous system that helps them navigate their way through the water. If until now it seemed to us that when a jellyfish lies on its back it stares helplessly at the sky, it turns out that it is actually looking for guidance and navigation.

In most previous studies, jellyfish were described as a low link in the chain of marine creatures, and in nature generally, but the new studies reveal that not only do they have a nervous system, but that this system is advanced almost like that of mammals and humans. While most animals produce electrical currents through sodium, jellyfish, like humans, can choose between sodium or calcium, which they absorb from the sun, in order to produce different kinds of currents.
“Therefore,” says Dr. Richard Sattlery, one of the editors of the second study, “a jellyfish can send double amounts of information through its nervous system, which enhances its communication abilities compared to other creatures.” He adds: “A jellyfish can do much more than people think. Research until now on this spineless creature has been shallow.”
For 6 years, Dr. David Albert studied jellyfish in Roscoe Bay in the United States. His point of departure was curiosity to discover how jellyfish cope with the phenomenon of the tides, which is common there, and how they manage to adopt a uniform response. He found that their behavior is quite organized and not passive at all: “When the ebb begins, they ‘ride’ the waves until they reach a point deep enough to dive back down. They remain in the calm water until the tide returns, and then choose to drift back into the bay.” He also found that jellyfish move through the water until they find a sufficient level of salinity that suits them.
Both studies ended on the note that there may be thousands more behaviors of other creatures that we are too quick to judge through our own conceptual world, without allowing for different behavioral patterns, and thus we are actually drawing a mistaken picture of the world.