[wombatmobile]

How might the nervous system have evolved?

Wikipedia says: "Action potentials, which are necessary for neural activity, evolved in single-celled eukaryotes. These use calcium rather than sodium action potentials, but the mechanism was probably adapted into neural electrical signalling in multicellular animals. In some colonial eukaryotes such as Obelia electrical signals do propagate not only through neural nets, but also through epithelial cells in the shared digestive system of the colony."

So, the first "thought" was "hungry, want food"?

And everything we do to get to the 7/11 for snacks is built on that?

[rolph]

cells can coordinate by diffusion of signal molecules larger multicellular organisms can use circulatory transport to reduce latency of signals. larger complex organisms coordinate systemic functions with neurons and the electrical signaling between distant parts of the body.

latency is not a good thing to have when you are a motile animal, it limits your overall size and complexity. animal phyla with nervous systems were able to evolve larger bodies avoid being consumed by being too big to eat and became consumers of smaller organisms.