
I have big ears. They are 3 1/2 inches long. African elephants have provided a new perspective. Theirs can be six feet long and five feet wide. “The better to hear with,” you might note. And elephants do have good hearing with a range from 14 to 16,000 hz. (Humans range from 20 to 20,000 hz in comparison.) The lower range is known as subsonic. Elephants can actually make subsonic sounds with their trunks that humans can’t hear but elephants can— up to miles away! The large flaps also serve to direct sound toward the inner ear. Think of cupping your hands behind your ears. It helps to say “eh.”
Of equal importance, an elephants ears play a big role in helping it to keep cool. The fancy name for this is thermoregulation, the process that allows your body to maintain its core temperature. For example, a message from your skin goes to your brain saying it’s hot. Your brain sends a message back to your skin: Sweat. Unlike us, elephants don’t have sweat glands except around their feet. They cope with Africa’s hot tropical sun using other methods. We’ve already discussed mud baths. Wrinkly skin is another.





Elephants enhance this process in various ways. Providing air to move the heat away and cool the ear is the most important. Elephants are known to stand in the wind with their ears out. The most common approach, however, is to flap their ears. In addition to providing a breeze for the ears, the flapping also fans the body and blows insects away. (I wish I could flap mine.) Watching a group of elephants crossing the savanna while flapping their ears is so common it’s iconic. Other methods include getting out of the sun and taking mud/water baths.

This caused me to think about another aspect of elephant behavior related to their ears. When the elephants came out of the mud bath I featured in my December 4 blog, they gave a vigorous shake to their ears. I thought at the time it was like, “Woohoo!” Thinking back, I wonder if they weren’t shaking the mud off of their ears. Given that the mud in general helps to keep them cool, protect them from sunburn, and frustrate biting bugs, why? My conclusion (for which I couldn’t find back up data) was that the mud coats their ears and reduces the ability of their blood vessels to transfer the heat to the air.







Given the years I have spent wandering in the wilderness, I’ve always been interested in animal tracks. And that certainly applies to elephants. But what interests me the most about elephant feet is how they ‘hear’ with them via seismic communication. Caitlin O’Connell-Rodwel, a Stanford researcher, has been returning to the same elephant watering hole in Namibia for over 25 years figuring out how they do it. Her work has demonstrated that African elephants exchange information by emitting low-frequency sounds through their trunks that travel dozens of miles through the ground. She believes this communication is the key in understanding the dynamics of elephant groups. “Announcements” can include warnings, mating calls and navigation instructions, e.g. “Don’t be alarmed sweetie, but I would really like to make it with you under the acacia tree next to the pond.” In a more passive sense, elephants can also keep track of each other through the sound of each other’s foot steps.
They “listen” with their feet in two ways. One is through touch. Just like us, elephants have receptors in their skin known as Pacinian corpuscles that are hardwired to the brain. On an elephant these are located around the edge of their feet. When an elephant is picking up sounds/vibrations, it presses its feet onto the ground, expanding their surface by as much as 20%. Signals are then sent to the brain for processing. While this isn’t hearing exactly, the message gets through. A second method called bone conduction is closer to real hearing. The elephant jabs its big toes into the ground and the vibrations are carried up through its body via bones to the inner ear where they are heard like sound vibrations coming through the air.

At first, I had planned to do one blog on elephants, then it was two. Now it is three. They are just too fascinating, at least for me. Next time I’ll get more into family life, eyes, teeth, bones, and even poop— a single elephant can produce up to one ton in a week!





























































































































































