The platypus is a funny little mammal found in Eastern Australia and Tasmania. Aside from echidnas (the also-very-weird Australian spiny anteaters) they are the only living mammals that lay eggs. This bizarro egg-laying, duck-billed, beaver-tailed, otter-toed, crocodile-bodied assemblage completely bamboozled European naturalists when they stumbled on it back in 1798. It just had to be an elaborate fraud concocted by Chinese taxidermists (who had a reputation for sewing random bits together into mythical beasts). The serious European museum folk spent countless hours digging around with scissors looking for the stitches. In reality, he is the last living descendant of an ancient proto-mammalian reptile. Or a post-reptilian mammal. It’s not always clear, but this funny little nocturnal predator has some crazy-cool strategies that are apparently still working just fine. For instance, he has the baffling habit of folding up his eyes, ears, and nostrils within his skin when he dives. So, how does he find the wiggly little crunchy creatures he likes best down there? How the heck does he know where he’s going? The answer turns out to be truly marvelous, an exquisite combination of braille and electrolocation. Could we emulate the genius of the platypus? Find out more in today’s entry of The Biomimicry Manual !
Our platypus’ legs are short and powerful; faintly crocodilian, with webbed forefeet and venomous spurs on the hind. He’s pretty much the only poisonous mammal out there (though watch out for those nasty little shrews- oh, and breaking newsflash, Lady Gaga was just bitten by a venomous slow loris, so I totally retract that). Hold it by the tail, okay, all you wannabe platypi wrestlers out there? Although this neurotoxin is only lethal to small mammals, the pain will apparently make you wish you were dead, and for weeks. And get this- morphine doesn’t make it any better. It seems the poison blocks the pain receptors themselves. Wouldn’t that technology be useful to understand and mimic?
So our fierce little beastie floats along the night-surface of fast-moving fresh-water, grinding his insect and crustacean prey between the horny, ridged pads he calls teeth. He’s got a monster appetite, gobbling over two pounds of critters every night. Periodically, he dives down like an otter to the riverbed floor, whisking his fleshy bill back and forth in the tumbling stones and gravel. He stirs up worms, snails, grubs, and yummy ‘yabbies’ (little prawns), snatches them up, and tucks them into his squirrely cheek pouches for his floating grind session.
But how does he find his way and his prey at the bottom of this swift dark stream, with his eyes, nose, and ears screwed so tightly shut? Scientists had been scratching their heads, until they found the tiny electroreceptors that cover his leathery bill, each one a magical mucus gland attached to a cord of nervous fiber. As he sweeps it side to side, sifting his way through the cobbles, he picks up minute electrical impulses generated by the muscle activity of his prey. Meanwhile, his bill also features a series of ultra-sensitive touch “mechanoreceptors,” (I love that word), each containing a simple pushrod device that triggers a nerve when pressed. Together, these two types of signals go straight to his little platypus brain, painting a sonar-like image of the riverbed and any creatures he might stir up there. You can think of it like using the time difference between thunder and lightning (traveling to you at the speed of sound and light, respectively) to anticipate a storm’s arrival. The electrical discharges from the prey’s muscles are like lightning, while disturbance ripples in the water are like thunder. Our platypus ‘calculates’ the time delay between the two to know where his dinner is hiding.
Such a brilliant design: multifunctional and effective, high-tech and low-tech. Surely we could find a use for this idea? How about sensors for the blind? I imagine a walking cane that combines electrolocation and touch. Or prosthetic fingers with feeling? Collision-avoidance in cars? Exploring virtual worlds in video games? Fine-scale manufacturing applications? Anywhere detailed tactile sensing would be useful… ideas?
Maybe the iPlatypus will be unveiled sometime soon. I will be first in line. But can I have my monotreme in stereo? Minus the venom?
An evolutionary biologist, writer, sustainability expert, and passionate biomimicry professional in the Biomimicry 3.8 BPro certification program, Dr. Tamsin Woolley-Barker blogs at BioInspired Ink and serves as Content Developer for the California Association of Museums‘ Green Museums Initiative. She is working on a book about organizational transformation inspired by nature.