Jellyfish are far more intelligent than previously thought.
Jellyfish are very clever animals
A new study has found that poisonous Caribbean box jellyfish can learn at a more complex level than ever imagined - despite not having a centralised brain.
Scientists say that the findings change the fundamental understanding of the animal's brain and could even reveal more details about human brains and the process of dementia.
Neurobiologist Professor Anders Garm, of the University of Copenhagen, said: "It was once presumed that jellyfish can only manage the simplest forms of learning, including habituation - the ability to get used to a certain stimulation, such as a constant sound or constant touch.
"Now, we can see that jellyfish have a much more refined ability to learn, and that they can actually learn from their mistakes. And in doing so, modify their behaviour."