Carson’s thesis that we were subjecting ourselves to slow poisoning by the misuse of chemical pesticides that polluted the environment may seem like … - Rachel Carson

There is also a response, not to familiar surroundings, but to cosmic forces. Every fortnight, on the moon's quarter, a batch of eggs is fertilized and taken into the brood chamber to begin its development. And at the same time the larvae that have been made ready during the previous fortnight are expelled into the sea. By this timing-this precise synchronizing with the phases of the moon-the release of young always occurs on a neap tide, when neither the rise nor the fall of the water is of great extent, and even for so small a creature the chances of remaining within the rockweed zone are good.

"Such plants are "weeds" only to those who make a business of selling and applying chemicals."

In the fish world many things are told by sound waves.