Unimagined Sensitivities, Part 5
Infrasound could be an 'early warning system' for elephants and other mammals.
Posted Jun 03, 2017
As land animals, elephants' means of communication and empathy are easier to identify than with dolphins and whales. By virtue of their magnificent trunks, they simultaneously feel and smell. They also listen to their fellows’ rumbles by feeling the vibrations created in the ground. Special receptors in their feet, called Pacinian corpusles, allow them to do this. Biologist Caitlin O'Connell-Rodwell calls elephants an “amazing infrasound detection machine.”
The ability is known to extend up to 25 miles. It (or something like it) might extend considerably farther given the instance noted earlier of a group of elephants in Zimbabwe that retreated to a corner of their preserve that was farthest from a murderous “culling” of elephants taking place 90 miles away. “Elephants are able to detect distress calls over large distances and are fully aware when their fellows are being killed,” asserts longtime researcher Cynthia Moss. (Safina, p. 92)
Such long distance communication could be accomplished through infrasound, i.e. sound that has a wavelength less than the 20 Hz threshold that distinguishes human hearing. Infrasound can travel vast distances unimpeded by land, air or water. Many animal species are capable of registering infrasound, among them elephants, hippos, giraffes, rhinos, alligators, and whales. It was naturalist Katy Payne of Cornell University who first intuited what might be happening based on her standing near an elephant cage at the zoo one day and feeling a peculiar “throb and flutter” in the air. It reminded her, she said, of the deep bass notes she experienced as a girl in church. (Payne, pp. 20-21)
Here is a moving account of infrasonic communication as noted by the late naturalist Lyall Watson. (Watson, p. 207) He was whale watching from the cliffs of the South African coast, and wrote:
"The sensation I was feeling on the clifftop was some sort of reverberation in the air itself….The whale had submerged and I was still feeling something. The strange rhythm seemed now to be coming from behind me, from the land, so I turned to look across the gorge…where my heart stopped.
"…Standing there in the shade of the tree was an elephant…staring out to sea!...A female with a left tusk broken off near the base….I knew who she was, who she had to be. I recognized her from a color photograph put out by the Department of Water Affairs and Forestry under the title “The Last Remaining Knysna Elephant.” This was the Matriarch herself.
"...She was here because she no longer had anyone to talk to in the forest. She was standing here on the edge of the ocean because it was the next, nearest, and most powerful source of infrasound. The under-rumble of the surf would have been well within her range, a soothing balm for an animal used to being surrounded by low and comforting frequencies, by the lifesounds of a herd, and now this was the next-best thing.
"…The throbbing was back in the air. I could feel it, and I began to understand why. The blue whale was on the surface again, pointed inshore, resting, her blowhole clearly visible. The Matriarch was here for the whale! The largest animal in the ocean and the largest living land animal were not more than a hundred yards apart, and I was convinced that they were communicating! In infrasound, in concert, sharing big brains and long lives, understanding the pain of high investment in a few precious offspring, aware of the importance and the pleasure of complex sociality, these rare and lovely great ladies were commiserating over the back fence of this rocky Cape shore, woman to woman, matriarch to matriarch, almost the last of their kind."
In my next post, we’ll delve more into infrasound and similar modes of animal sensitivity.
“Eyewitness Accounts: Gehan De Silva Wijeyeratne.” Nature, June 3, 2008. http://www.pbs.org/wnet/nature/can-animals-predict-disaster-gehan-de-silva-wijeyeratne/139/.
Safina, Carl. Beyond Words: What Animals Think and Feel. New York: Henry Holt & Co., 2015.
Payne, Katy. Silent Thunder: In the Presence of Elephants. New York: Simon & Schuster, 1998.
Watson, Lyall. Elephantoms: Tracking the Elephant. New York, Norton, 2003.