The Dolphin in the Mirror

Exploring Dolphin Minds and Saving Dolphin Lives

by Diana Reiss

Houghton Mifflin Harcourt

Dogs are the secret weapons on land, but dolphins are the badasses of the sea.

Dolphins, one of the quickest sea animals and easily one of the smartest animals on Earth, have such highly attuned auditory-based navigation systems, called echolocation, that the military has been using them for decades.

“Dolphin echolocation is the envy of the military,” writes dolphin researcher Diana Reiss, author of the forthcoming study on dolphin behavior and intelligence.

At a distance of 30 feet, a dolphin can detect tenths of a milliliter difference (about the thickness of a fingernail) in density of walls. They can locate sources of sound underwater, their high-frequency range hitting 150 kilohertz, compared to 20 kilohertz for a human.

A dolphin has a “clear acoustics image of its surroundings. Dolphins can almost literally see with sound,” Reiss writes.

It has even been suggested, but still unproven, that dolphins have biological sonar, which allows them to see the internal bodies of others.

“So imagine having X-ray vision and being able to scan the internal bodies of your family members and friends; you’d know about their pregnancies, injuries and illnesses,” she writes.

It’s no wonder that the US government uses dolphins to locate undersea mines and stranded divers, although they deny using these animals in any sort of combat situation. Still, there are rumors that the military uses them for tracking submarines and even have attempted to outfit them in high-tech assault gear.

These theories were only buoyed when it was revealed years later, in 2000, that the Soviet Union had sold several dolphins to Iran. These dolphins, called “mercenaries,” were trained to attack warships and could even differentiate between the Soviet ships and enemies by sound, according to the BBC.