"For example, it was thought that as different kinds of animals evolved and the nervous system became more complex ... enough ...

For example, they have a unique nervous system consisting of nerve cells that merge together to form a continuous net-like structure, rather than having individual nerve cells like other animals.

In a comb jelly’s nervous ... of the animal’s nervous system. The group used an electron microscope that takes several images as a diamond knife shaves off the top section of the sample ...

BSE is a non-contagious but chronic degenerative disease affecting the central nervous system of cattle ... BSE has been confirmed on a farm in Essex. The animal died on farm and was tested ...