Dolphins—like humans, great apes, and elephants, among other creatures—are self-aware. This was first proven by animal cognition researcher Diana Reiss, who gave dolphins the mirror self-recognition test, in which researchers place a mark on an animal where the animal can’t see it—above a dolphin’s eye, for example—then watch how the animal reacts in front of a mirror. Dolphins passed the test with flying colors. Also, they loved using the mirror to look at their own genitals, which are positioned in a place they can’t normally see. (Reiss has some great video footage of this.)

In another groundbreaking study, Reiss designed an underwater keyboard composed of nine blank keys that could be fitted with simple white symbols. When a dolphin pressed a key, the animal would hear a synthesized whistle, then get the treat associated with the symbol: a ball, a fish, a rub on the belly. Remarkably, the dolphins not only pressed the symbols for items they preferred, they quickly learned to imitate the whistles and incorporated them into their communication with each other. Reiss is still trying to figure out what they’re saying. 

A professor of psychology at Hunter College in the graduate program of Biopsychology and Behavioral Neuroscience, Reiss was a scientific adviser on the Academy Award-winning documentary The Cove and is the author of The Dolphin in the Mirror: Exploring Dolphin Minds and Saving Dolphin Lives. 

When I arrived at her apartment on Manhattan’s Upper West Side, she was on the phone, frantically arranging for the rescue of a massive black Newfoundland, who would arrive (drooling heavily) on her doorstep just a few days later. She apologized profusely for the delay as we settled onto the plush white couches in her living room. As we 50 talked, her giant black cat sashayed between us, its bushy tail tickling our noses.

—Meehan Crist

I. FAMILIARITY BREEDS INTERPRETATION

THE BELIEVER: Your career as a scientist has been built on trying to understand animal minds, a project that, up until just a few decades ago, would have been rejected by much of the scientific community. Scientists were supposed to look only at behavior. So I wonder what you mean when you say, in your book, “Consciousness should, in principle, be available to scientific inquiry.”

DIANA REISS: It doesn’t mean we should understand it, but we should at least find ways to look at it. I think it challenges scientists to think about, first of all: how do we define consciousness? Is it something separate from just the processing of the brain? Because maybe that’s all it is, and that’s fine, but we need to define it, at least, so we can say, “If we see this...