On March 23, Future Tense—a partnership of Slate, the New America Foundation, and Arizona State University that explores emerging technologies, policy, and society—will hold a live event in Washington, D.C., on the concept of resilience. Academics, policymakers, and other experts will discuss resilience in the environment, business, national security, even the Constitution. Slate’s Matt Yglesias and Emily Bazelon will be there, too. To learn more and to RSVP, click here.
When most people look at sharks, they’d be hardpressed to find any redeeming features. Many of them have ferocious jaws, sandpapery skin, and frightening senses that can zero in on their hidden prey. Their best assets, in other words, are threats to our existence.
But these predatory advantages hold the promise of engineering solutions that could help sustain—rather rather than kill—humans. Their hardened skin has inspired faster ships; their ability to detect weak vibrations underwater may eventually yield a better battery. The movie Jaws convinced us that sharks are unparalleled stalkers, but it failed to capture how these skills could apply to our daily existence.
The field of biomimicry—imitating a natural process for human purposes—has existed for decades. In 1948, Swiss inventor George de Mestral took a hike in the Alps with his dog, and after they both returned covered in burrs, de Mestral examined the seed sacs under a microscope. He mimicked the mechanism they used to attach themselves to softer surfaces—firm hooks paired with loops—to create Velcro, the ubiquitous fastener that has practically eliminated the need for children in developed countries to learn to tie their shoelaces.
But in recent years the idea has taken on more urgency, especially among environmentalists. According to the fossil record, the historic rate of extinction was roughly one species per million before humans started having a major impact on the planet; experts such as biologist E.O. Wilson estimate that humans have accelerated this rate by a factor of at least 1,000, if not 10,000. Roughly one-third of all shark species worldwide face some threat of extinction, according to the International Union for Conservation of Nature.
People are moved by the plights of endangered animals, but that sympathy typically does not amount to much. Biomimicry offers a new way to save animals like sharks—by appealing to humanity’s profit-minded nature. If plant and animal species can inspire technological innovation, points out the U.N. Environmental Programme’s Nick Nutall, they can earn their keep: “In a world fascinated by GDP, if you cannot demonstrate the value of nature it’s always going to be subject to the ups and downs and vagaries of nations’ economies,” he says.
The list of possible breakthroughs inspired by shark physiology is a lengthy one.
In additional to boasting all of the ordinary senses that humans have, sharks possess something called electroreception. A row of small holes that runs from head to tail picks up weak vibrations. This network, along with tiny, fluid-filled sacs in their snouts and chins known as ampullae of Lorenzini, helps sharks find fish buried in the sand because they can detect the electromagnetic fields generated by a fish’s beating heart or gills. Other fish have a lateral line to sense movement, but they do not have the gelatinous material that serves as a conductor for electric vibrations, radiating these signals out to a shark’s nervous system. Scientists across the United States are hoping to capitalize on sharks’ unique voltage-charged gel for practical purposes. University of San Francisco physics professor Brandon R. Brown has extracted the material from dead sharks to gauge its thermal sensitivity, while Case Western Reserve University nanoengineering professor Alexis Abramson has explored developing a synthetic gel with similar thermoelectric properties that could be used to convert waste heat, from devices such as a car engine, into usable electricity.
Then there are sharks’ denticles—otherwise known as “skin teeth”—which cover their bodies. Made up of crowns covered with hard enamel, they reduce friction by forcing the water to flow in channels, allowing sharks to move swiftly through the water. The type of denticles a shark has depends on the species: Lighter denticles maximize a shark’s speed while providing slightly less protection from a predatory attack. (Basking sharks have crowns that point in all directions, while short-fin mako sharks—some of the fastest swimmers in the sea—have smaller, lighter denticles.) They are as strong as steel and carry an added benefit: By minimizing water turbulence, they allow sharks to hunt better by moving through the sea in near silence.
Ralph Liedert, a researcher at the University of Applied Sciences in Bremen, Germany, pioneered the idea of covering ships with artificial sharkskin to help them move smoothly by dramatically reducing biofouling (not to be confused with the more familiar biofueling). Biofouling, which occurs when barnacles, mussels, and algae latch onto ships, increases a vessel’s drag resistance by as much as 15 percent. Liedert has produced an imitation sharkskin from elastic silicone that would reduce this fouling by 67 percent, and he estimates that once a ship reached four to five knots, nearly all of these creatures would fly off the hull’s surface.
Researchers from Mote Marine Laboratory’s Center for Shark Research are looking at other aspects of how sharks operate. Along with scientists at Boston University’s marine program, they’ve learned that sharks hunt prey by sensing the differences when their smell hits each nostril—they call it “smelling in stereo.” In time, they hope to apply this steering algorithm to odor-guided robots that track oil plumes and chemical leaks underwater. And while plenty of quacks have tried to capitalize on how sharks rarely get cancer (shark cartilage may very well be the modern snake oil, especially since it’s likely high in toxins), Mote senior scientist Carl Luer is studying a shark-derived substance which kills cancerous cells in a Petri dish.
And for the more superficial among us, there’s even a cosmetic reason to appreciate sharks. Several beauty product firms have touted squalene, a substance derived from sharks’ livers that helps keep them buoyant, as a moisturizing agent. After scientists complained the squalene trade was taking too heavy a toll on long-lived deepwater sharks, the Silicon Valley biotech firm Amyris found a way to produce squalene from plant sugars without a negative environmental impact.
Sharks are not the only marine creatures that may end up improving our lives if we learn how to imitate them. The German Aerospace Centre recently completed a rotor blade efficiency study connected to humpback whales, which have bumps on the front edge their pectoral fins that increase their buoyancy. Mimicking this shape on a rotor blade can counteract a phenomenon in helicopter flight called “dynamic stall” that increases turbulence and reduces their maneuverability.
Not all of these developments will translate into sustainable business practices, of course, and there’s a danger to overhyping the potential here. Dayna Baumeister, co-founder of Biomimicry 3.8, wonders whether inventors will continue to be friends of the environment once their products are on the market. We could imitate the whales and then hunt them as soon as we perfect our rotor blades, or make sharks’ fins into soup once we develop cancer-fighting drugs inspired by them.
But maybe we’re a little smarter than that, even if we lack armored skin and electroreception.