By Yishane Lee
As a friend of HHF, you are no doubt well aware that chicks, fish, and reptiles have the ability to regenerate their inner ear hair cells, an ability that means any damage to their hearing is corrected.
Mammals, including humans, cannot, and this is the core of what HHF’s Hearing Restoration Project is working to solve within the next decade—how we can translate the chick’s ability to regrow hair cells to humans, and as a result find a biologic cure for hearing loss and tinnitus.
Now comes news that it is not just the animal world that can hear. Plants can, too. A recent story by Michael Pollan in the New Yorker included this paragraph (italics mine):
“Plants have evolved between 15 and 20 distinct senses, including analogues of our five: smell and taste (they sense and respond to chemicals in the air or on their bodies); sight (they react differently to various wavelengths of light as well as to shadow); touch (a vine or a root ‘knows’ when it encounters a solid object); and, it has been discovered, sound. In a recent experiment, Heidi Appel, a chemical ecologist at the University of Missouri, found that, when she played a recording of a caterpillar chomping a leaf for a plant that hadn’t been touched, the sound primed the plant’s genetic machinery to produce defense chemicals. Another experiment, done in [Italian plant physiologist Stefano] Mancuso’s lab and not yet published, found that plant roots would seek out a buried pipe through which water was flowing even if the exterior of the pipe was dry, which suggested that plants somehow ‘hear’ the sound of flowing water.”
I find this absolutely fascinating. Could it be the plants “hear” via sensing sound vibrations—just like we do? And then they’re able to correctly correlate these vibrations to the category of friend or foe—again, just like we do? To hear the plant biologists in the story put it: Yes, it’s entirely possible, and even likely.
The article raises interesting issues of why animal-based biology deserves primacy, and whether a typical (animal) brain is needed for something to be considered intelligent. In addition to reading the piece, which I highly encourage you to do, there is a TED Talk by Mancuso, if you want to learn more.