By: Julie Nelson
Unlike humans, dolphins will never know the state of fear and confusion that comes with trying to find a light switch in the dark. Like bats of the sea, these and other marine animals have something we don’t – echolocation.
Perhaps this advantage is what gives them that adorably permanent smirk.
While dolphins don’t need a pair of “fashionable” goggles to be able to see underwater – murky, unclear or dark water can still be a problem for them. With the ocean world so full of diverse sounds, dolphins have adapted the way they hear and see.
Dolphins have retained most of the basic senses, except for the abandoned sense of smell. Enter echolocation.
The dolphins’ external ears packed their bags and moved to warmer waters somewhere along the evolutionary path, which made their bodies more streamlined and gave the inner ears room to shine. Their inner ears are isolated from each other acoustically to allow them to pinpoint sounds. They are also able to pick up sounds on extremely high frequencies, which is part of what makes echolocation possible.
According to studies done at SeaWorld, dolphins send out a series of high-intensity clicks into the surrounding water to “see” what is around them. The sound waves are sent out in a beam from the dolphin’s fatty melon, and the echo is later received through the fatty tissue on the jaw bones. Bottle line in dolphin world? Having a fat head just means you have excellent hearing.
When the sound waves come in contact with an object or other animal, its echo is sent back to the dolphin and interpreted through its special hearing pathways.
The echo provides information on objects such as distance, size, shape, speed and even internal structures. For example, The Dolphin Institute reports that spotted and bottlenose dolphins have been observed using echolocation on the sand at the bottom of the ocean to discover hidden fish (a.k.a. snacks that thought they could hide).
So if echolocation is so fine-tuned in dolphins, how important is their actual vision? Turns out echolocation and eyesight work together to navigate the ocean world.
The actual sights a dolphin sees are matched with the echo that it interprets to build a better picture in the dolphin’s mind. A vision impaired dolphin can still locate an object, however, it will take much longer than usual.
Basically when it comes to seeing what lives beneath the waves, team work makes it happen.
“Cheers to the reigning champions of Underwater Marco Polo.” – Humans Everywhere