Introduction
The brain and nervous system have been created during the Cambrian
period, therefore this occurrence is based on a molecular level which is
followed by numerous consequences for rapid development and evolution of
the nervous system. (Miklos 1993) In the past, it was thought that only
human beings possess brain processing and different behavior, but now,
according to evidence and carried studies it has been shown that these
systems have started to evolve in invertebrates. (Frasnelli 2013) The
investigations based on proteins, DNA, neurons, nervous systems, and
cognitive levels have been done in both invertebrates and vertebrates.
(Miklos 1993)