" Hormones and neurotransmitters, the chemicals associated with human desire, fear, love, joy, and sadness, “are highly conserved across taxa,” Jennifer said. This means that whether you’re a person or a monkey, a bird or a turtle, an octopus or a clam, the physiological changes that accompany our deepest-felt emotions appear to be the same. Even a brainless scallop’s little heart beats faster when the mollusk is approached by a predator, just like yours or mine would do were we to be accosted by a mugger. "

― Sy Montgomery , The Soul of an Octopus: A Surprising Exploration Into the Wonder of Consciousness