In the 1960s, the Central Intelligence Agency recruited an unusual field agent: a cat. In an hour-long procedure, a veterinary surgeon transformed the furry feline into an elite spy, implanting a microphone in her ear canal and a small radio transmitter at the base of her skull, and weaving a thin wire antenna into her long gray-and-white fur. This was Operation Acoustic Kitty, a top-secret plan to turn a cat into a living, walking surveillance machine. The leaders of the project hoped that by training the feline to go sit near foreign officials, they could eavesdrop on private conversations.
The problem was that cats are not especially trainable — they don’t have the same deep-seated desire to please a human master that dogs do — and the agency’s robo-cat didn’t seem terribly interested in national security. For its first official test, CIA staffers drove Acoustic Kitty to the park and tasked it with capturing the conversation of two men sitting on a bench. Instead, the cat wandered into the street, where it was promptly squashed by a taxi. The program was abandoned; as a heavily redacted CIA memo from the time delicately phrased it, “Our final examination of trained cats … convinced us that the program would not lend itself in a practical sense to our highly specialized needs.” (Those specialized needs, one assumes, include a decidedly unflattened feline.)
Operation Acoustic Kitty, misadventure though it was, was a visionary idea just 50 years before its time. Today, once again, the U.S. government is looking to animal-machine hybrids to safeguard the country and its citizens. In 2006, for example, DARPA zeroed in on insects, asking the nation’s scientists to submit “innovative proposals to develop technology to create insect-cyborgs.”
It was not your everyday government request, but it was an utterly serious one. For years, the U .S. military has been hoping to develop “micro air vehicles” — ultrasmall flying robots capable of performing surveillance in dangerous territory. Building these machines is not easy. The dynamics of flight change at very small sizes, and the vehicles need to be lightweight enough to fly yet strong enough to carry cameras and other equipment. Most formidably, they need a source of power, and batteries that are light enough for microfliers just don’t have enough juice to keep the crafts aloft for very long. Consider two of the tiny, completely synthetic drones that engineers have managed to create: The Nano Hummingbird, a flying robot modeled after the bird, with a 6.5-inch wingspan, maxes out at an 11-minute flight, while the DelFly Micro, which measures less than four inches from wingtip to wingtip, can stay airborne for just three minutes.
DARPA officials knew there had to be something better out there.
“Proof-of-existence of small-scale flying machines … is abundant in
nature in the form of insects,” Amit Lal, a DARPA program manager and
Cornell engineer, wrote in a pamphlet the agency issued to the
prospective researchers. So far, nature’s creations far outshine our
own. Insects are aerodynamic, engineered for flight and naturally
skilled at maneuvering around obstacles. And they can power themselves; a
common fly can cruise the skies for hours at a time. So perhaps, DARPA
officials realized, the military didn’t need to start from scratch; if
they began with live insects, they’d already be halfway to their dream
flying machines. All they’d have to do was figure out how to hack into
insects’ bodies and control their movements. If scientists could manage
to do that, the DARPA pamphlet said, “it might be possible to transform
[insects] into predictable devices that can be used for … missions
requiring unobtrusive entry into areas inaccessible or hostile to
humans.”
DARPA’s call essentially launched a grand science fair, one designed to encourage innovation and tap into the competitive spirit of scientists around the country. The agency invited researchers to submit proposals outlining how they’d create steerable insect cyborgs and promised to fund the most promising projects. What the agency wanted was a remote-controlled bug that could be steered to within five meters of a target. Ultimately, the insects would also need to carry surveillance equipment, such as microphones, cameras or gas sensors, and to transmit whatever data they collected back to military officials. The pamphlet outlined one specific application for the robo-bugs — outfitted with chemical sensors, they could be used to detect traces of explosives in remote buildings or caves — and it’s easy to imagine other possible tasks for such cyborgs. Insect drones kitted out with video cameras could reveal whether a building is occupied and whether those inside are civilians or enemy combatants, while those with microphones could record sensitive conversations, becoming bugs that literally bugged you.
As far-fetched and improbable as DARPA’s dream of steerable robo-bugs sounds, a host of recent scientific breakthroughs means it’s likely to be far more successful than Acoustic Kitty was. The same advances that enabled the development of modern wildlife-tracking devices — the simultaneous decrease in size and increase in power of microprocessors, receivers and batteries — are making it possible to create true animal cyborgs. By implanting these micromachines into animals’ bodies and brains, we can seize control of their movements and behaviors. Genetics provides new options, too, with scientists engineering animals whose nervous systems are easy to manipulate. Together, these and other developments mean that we can make tiny flying cyborgs — and a whole lot more. Engineers, geneticists and neuroscientists are controlling animal minds in different ways and for different reasons, and their tools and techniques are becoming cheaper and easier for even us nonexperts to use. Before long, we may all be able to hijack animal bodies. The only question is whether we’ll want to.
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DARPA’s call for insect cyborgs piqued the interest of Michel Maharbiz, an electrical engineer at the University of California, Berkeley. He was excited by the challenge of creating flying machines that merged living bodies and brains with electronic bits and bytes. “What I wanted at the end of the day was a remote-controlled airplane,” Maharbiz recalls. “What was the closest thing to a remote-controlled airplane that I could get with these beetles?”
Maharbiz was an expert at making small electronic devices but an amateur when it came to entomology. So he started reading up. He figured that most scientists taking on DARPA’s challenge would work with flies or moths, longtime laboratory superstars, but Maharbiz came to believe that beetles were a better bet. Compared with flies and moths, beetles are sturdy animals, encased in hard shells, and many species are large enough to carry significant cargo. The downside: Scientists didn’t know much about the specific nerve pathways and brain circuits involved in beetle flight.
That meant that the first challenge was to unravel the insects’ biology. Maharbiz and his team began working with several different beetle species and eventually settled on Mecynorrhina torquata, or the flower beetle. It is a scary-looking bug — more than two inches long, with fearsome claws and a rhinoceros-like horn on the forehead. Through trial and error, the scientists homed in on a promising region of the beetle brain nestled at the base of the optic lobes. Previous research had shown that neural activity in this area helped keep the insect’s wings oscillating, and Maharbiz’s team discovered that when they stimulated this part of the brain in just the right way, they could start and stop beetle flight. When they sent a series of rapid electrical signals to the region, the beetle started flapping its wings and readied itself for takeoff. Sending a single long pulse to the same area prompted the insect to immediately still its wings. The effect was so dramatic that a beetle in mid-flight would simply fall out of the air.
After he discovered these tricks, Maharbiz was ready to try building the full flying machine. The flower beetle’s transformation began with a quick trip to the freezer. In the icy air, the beetle’s body temperature dropped, immobilizing and anesthetizing the insect. Then Maharbiz and his students removed the bug from the icebox and readied their instruments. They poked a needle through the beetle’s exoskeleton, making small holes directly over the brain and the base of the optic lobes, and threaded a thin steel wire into each hole.
They made another set of holes over the basalar muscles, which modulate wing thrust and are located on either side of the beetle’s body. The researchers pushed a wire into the right basalar muscle. Stimulating it would cause the beetle’s right wing to start beating with more power, making the insect veer left. They put another wire into the left basalar muscle; they would use it to steer the beetle to the right. The loose ends of all these wires snaked out of their respective holes and plugged into a package of electronics mounted with beeswax on the beetle’s back. This “backpack” included all the equipment Maharbiz needed to wirelessly send signals to the beetle’s brain: a miniature radio receiver, a custom-built circuit board, and a battery.
Then it was time for a test flight. One of Maharbiz’s students called up their custom-designed “Beetle Commander” software on a laptop. He issued the signal. The antennae jutting out of the beetle’s backpack received the message and passed it along to the circuit board, which sent electricity surging down the wire and into the beetle’s optic lobe. The insect’s wings began to flap. The empty white room the researchers used as an airfield filled with a buzzing sound, and the bug took flight. The beetle flew on its own — it didn’t need any further direction from human operators to stay airborne — but as it cruised across the room, the researchers overlaid their own commands. They pinged the basalar muscles, prompting the beetle to weave back and forth through the room, as if flying through an invisible maze. It wouldn’t have looked out of place going up against a stunt pilot at an air show. Another jolt of electricity to the optic lobe, and the beetle dropped out of the air and skittered across the tile floor.
As soon as Maharbiz presented his work, the news stories came fast and furious, with pronouncements such as, “The creation of a cyborg insect army has just taken a step closer to reality,” “Spies may soon be bugging conversations using actual insects, thanks to research funded by the U.S. military” and more. A columnist speculated about the possibility of a swarm of locust drones being used as vehicles for launching deadly germs. There was chatter about beetles that had been “zombified,” and references to “the impending robots vs. humans war.”
When Maharbiz reflects upon this media frenzy, he admits that the immense public interest in his work doesn’t surprise him. The research, after all, is practically primed to light up the futuristic-fantasy centers of our brains. Insects, even without modifications, seem like weird, alien organisms to many of us. As Maharbiz explains, “Insects have inherently some sort of strange, science fiction quality that a bunny doesn’t have.” Add in miniature electronics, flying devices, animal-machine hybrids, and covert military operations, and you have a recipe for dystopian daydreaming.
But Maharbiz bristles at the most sinister suggestions, at the media coverage that suggests his beetles are the product of, as he puts it, “some evil government conspiracy.” As for the possibility that the U.S. government is planning to use the bugs to build a killer insect army or to spy on its own citizens? “I think that’s nonsense,” he says. His beetles haven’t been sent out into the field yet — they still need some refinement before they’re ready for deployment — but if and when they are, Maharbiz says he expects his bugs to be used abroad in routine military operations. (Of course, some people may find that “equally reprehensible,” he acknowledges.) There are civilian applications, too. Imagine, Maharbiz tells me, an army of beetle-bots, steered to the scene of an earthquake. The bugs could be outfitted with temperature sensors, guided through rubble and programmed to send messages back to search teams if they detect any objects that are close to human body temperature; rescuers would then know exactly where to search for survivors.
Whatever the application, future insect commanders will have options that go beyond beetles. Maharbiz is working on a remote-controlled fly, which he anticipates being especially difficult to build. “The fly is so small and the muscles are so packed and everything’s so tiny,” he says, that even just implanting the electronics will be challenging. A Chinese research team has managed to start and stop flight in honeybees, and Amit Lal, the engineer who led the DARPA program, has created steerable cyborg moths.
One of Lal’s innovations has been figuring out how to take advantage of morphogenesis, the process by which many species of insects transform from wriggling larvae to spindly, multilegged adults. During pupation, a baby insect wraps itself in a protective cocoon or shell while its soft, immature body becomes a more structurally complex adult one. (Lal’s species of choice is the tobacco hawk moth, which morphs from a bright green worm into a brown-and-white spotted moth.) To Lal, this phase of the insect life cycle presented a unique opportunity; he hoped that if he inserted electronic components into a hawk moth when it was a wee pupa, the bug’s body would rebuild itself around the implant. In one set of experiments, Lal and his colleagues pushed thin wires through the hard shell that protects a hawk moth pupa and positioned them in the insect’s neck muscles and brain. Outside the bug’s body, the wires linked up with a small circuit board, which the researchers left resting loosely atop the pupal case. They repeated the procedure with 29 more pupae and then tucked them all away inside an incubator and allowed them to develop normally.
About a week later, the insects shed their shells, emerging as fully grown moths. Their bodies had in fact fashioned themselves around the implants; tissue had grown around the wires, securing them in place. The wires ran out of the moths’ heads and partway down their backs, winding their way into the attached circuit board. All researchers had to do to begin steering the moths was plug their control system into the circuit board, a task that took a matter of seconds.
These kinds of pupal surgeries have much to recommend them, the researchers say. They lead to more stable, permanent interfaces between electronic devices and living tissue. The approach may also be less traumatic for the animals; bugs heal easily during pupation, and since the adults are born with circuit boards hanging out of their backs, they’re less likely to perceive them as foreign objects or extra weight. (After all, the bugs will never know a life in which they aren’t attached to circuit boards.) It’s also much easier to operate on a pupa than an adult insect. The procedure is so simple that it could enable the “mass production of these hybrid insect-machine systems,” the scientists wrote.
Still, the robo-bugs aren’t quite ready for their tour of duty. Our directional control is still pretty crude. Ultimately, we’ll want to do more than make an insect simply veer left. We’ll want to be able to command it to turn, say, precisely 35 degrees to the left or navigate a complicated three-dimensional space, such as a chimney or pipe. There’s also the matter of the surveillance equipment. So far, the main focus has been on building insects that we can steer, but for these cyborgs to be useful, we’ll need to outfit them with various sensors and make sure that they can successfully collect and transmit environmental information. And though the cyborg insects power their own flight — something that completely robotic fliers cannot do — the surveillance equipment will need to get its electricity from somewhere.
One intriguing possibility is to use the insect’s own wings as a source of power. In 2011, a team of researchers from the University of Michigan announced that they had accomplished just that by building miniature generators out of ceramic and brass. Each tiny generator was a flattened spiral — imagine the head of a thumbtack, if it were shaped from a tight coil of metal rather than a single flat sheet — measuring 0.2 inches across. When they were mounted on the beetle’s thorax, these generators transformed the insect’s wing vibrations into electrical energy. With some refinement,the researchers note, these energy-harvesting devices could be used to power the equipment toted around by cyborg bugs.
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Insects could give us a cyborg-animal air force, zooming around the skies and searching for signs of danger. But for terrestrial missions, for our cyborg-animal army, we’d have to look elsewhere. We’d have to look to a lab at the State University of New York (SUNY) Downstate, where researchers have built a remote-controlled rat.
We’ve been rooting around in rat brains for ages; neuroscientists often send electrical signals directly into rodents’ skulls to elicit certain reactions and behaviors. Usually, however, this work requires hooking a rodent up to a system of cables, severely restricting its movement. When the SUNY team, led by the neuroscientist John Chapin, began their work more than a decade ago, they wanted to create something different — a method for delivering these electrical pulses wirelessly. They hoped that such a system would free researchers (and rats) from a cumbersome experimental setup and enable all sorts of new scientific feats. A wireless system would allow scientists to manipulate a rat’s movements and behaviors while it was roaming freely and give us a robo-rodent suitable for all sorts of special operations. Rats have an excellent sense of smell, so cyborg rats could be trained to detect the scent of explosives, for instance, and then steered to a field suspected to contain land mines. (The task would pose no danger to the animals, which are too light to set off mines.) Or they could be directed into collapsed buildings and tasked with sniffing out humans trapped beneath the rubble, performing a job similar to the one Maharbiz imagines for his cyborg insects. “They could fit through crawl spaces that a bloodhound never could,” says Linda Hermer-Vazquez, a neuroscientist who was part of the SUNY team at the time.
But before any of that could happen, the SUNY scientists had to figure out how to build this kind of robo-rat. They began by opening up a rat’s skull and implanting steel wires in its brain. The wires ran from the brain out through a large hole in the skull, and into a backpack harnessed to the rodent. (“Backpack” seems to be a favorite euphemism among the cyborg-animal crowd.) This rat pack, as it were, contained a suite of electronics, including a microprocessor and a receiver capable of picking up distant signals. Chapin or one of his colleagues could sit five hundred yards away from the rat and use a laptop to transmit a message to the receiver, which relayed the signal to the microprocessor, which sent an electric charge down the wires and into the rat’s brain.
To direct the animal’s movements, the scientists implanted electrodes in the somatosensory cortex, the brain region that processes touch sensations. Zapping one area of the cortex made the rat feel as though the left side of its face was being touched. Stimulating a different part of the cortex produced the same phantom feeling on the right side of the rat’s face. The goal was to teach the rodent to turn in the opposite direction of the sensation. (Though that seems counterintuitive, it actually works with the rat’s natural instincts. To a rodent, a sensation on the right side of the face indicates the presence of an obstacle and prompts the animal to scurry away from it.)
During the training process, the SUNY scientists used an unconventional system of reinforcement. When the rat turned in the correct direction, the researchers used a third wire to send an electrical pulse into what’s known as the medial forebrain bundle (MFB), a region of the brain involved in processing pleasure. Studies in humans and other animals have shown that direct activation of the MFB just plain feels good. (When the scientists gave the rats the chance to stimulate their own MFBs by pressing down on a lever, the animals did so furiously — hitting the lever as many as 200 times in 20 minutes.) So sending a jolt of electricity zinging down to a rat’s MFB acted as a virtual reward for good behavior. Over the course of 10 sessions, the robo-rats learned to respond to the cues and rewards being piped into their brains. Scientists managed to direct the rodents through a challenging obstacle course, coaxing them to climb a ladder, traverse a narrow plank, scramble down a flight of stairs, squirm through a hoop and then navigate their way down a steep ramp.
As a final demonstration, the researchers simulated the kind of search-and-rescue task a robo-rat might be asked to perform in the real world. They rubbed tissues against their forearms and taught the rodents to identify this human odor. They constructed a small Plexiglas arena, filled it with a thick layer of sawdust, and buried human-scented tissues inside. When they released the robo-rats into the arena, the animals tracked down the tissues in less than a minute. The scientists also discovered that the rats that received MFB rewards found the target odors faster and dug for them more energetically than rodents that had been trained with conventional food rewards. As Hermer-Vazquez recalls: “The robo-rats were incredibly motivated and very accurate.”
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Whether it’s rescue rat-bots or bomb-sniffing beetle drones, electronics are helping us create new beasts of burden, allowing us to conscript creatures into the modern animal workforce. These are no mere donkeys, poked and prodded into carrying our bags up steep hills; these animals’ brains are being taken hostage, their nervous systems forced to cooperate with our plans. As Maharbiz wrote in an account of his research, “[W]e wanted to be sure we could deliver signals directly into the insect’s own neuromuscular circuitry, so that even if the insect attempted to do something else, we could provide a countercommand. Any insect that could ignore our commands would make for a crummy robot.”
Is it wrong to take the reins of another creature’s nervous system? It certainly feels wrong. When we dictate the movements of sentient beings, we turn them into mere machines, no different than those remote-controlled airplanes Maharbiz was trying to emulate. Many animal liberationists and philosophers have argued that one of our obligations to animals is “noninterference” — that animals have the right to be the leaders of their own lives and that we have a duty to leave them alone. Cyborg animals represent an extreme violation of that responsibility. And unlike in wildlife tracking projects, in which our meddling may help save species, deploying cyborg insects and rodents on the battlefield isn’t going to do much to benefit animals.
The trouble is that we have to balance this intrusion into the life of another living being against the good that animal-machine mash-ups could do. It’s possible to care about animals and want to spare them needless suffering, and yet also decide that sometimes human welfare (say, the life of an American soldier) comes first. In fact, most Americans take this view, according to the psychologist Harold Herzog, who specializes in untangling our relationships with other species. After all, if you insist that an animal’s life is worth exactly the same as a human one, no matter what, Herzog says, “you can end up at untenable places.” (Such as deciding that you should flip a coin to decide whether to save a puppy or a child from a burning building.) Herzog has found that our attitudes toward other species are nuanced, complicated and often inconsistent. It’s not unusual, he says, to wish we could do without animal experimentation but still be grateful for the lifesaving drugs and treatments such research has made possible. It’s not strange to wish scientists would stop squirting shampoo into rabbits’ eyes and simultaneously want them to use as many bunnies as they need to find a cure for cancer.
Unless we rule out all use of animals for human purposes, we have to evaluate each application on a case-by-case basis, weighing pain against gain. In the case of the robo-beasts, the animals are anesthetized when the electronics are implanted in their bodies, but recovering from surgery isn’t painless. The devices themselves may cause stress, and being piloted around a lab by an ambitious postdoc can’t be any great picnic. But the price that animals have to pay for this research is relatively small. (Maharbiz notes that his beetles had normal lifespans — which, in insects, is a none-too-impressive several months — and “flew, ate, and mated just like regular beetles.”) Remotely guided rats aren’t exactly a cure for cancer, but if they can hunt down mines or find earthquake victims trapped in rubble, they could certainly save human lives. So while the cyborg research can seem creepy, I’m glad that there are scientists out there who are doing it.
The details matter, however. I wouldn’t be so keen on the research if the cost to animals were greater — if, say, each electric jolt we sent to an animal’s brain caused excruciating pain. Nor would I want to see robo-rats used to string lights along the branches of Christmas trees — an actual suggestion the SUNY researchers made in their patent application. There’s a species effect in play, too. I have no special affection for insects or rodents, and I’d find it a lot harder to sanction the creation of robo-dogs or robo-bonobos. Maharbiz has noticed this inconsistency, too, though it’s not clear where that leaves us, ethically speaking. “Where do you draw the line?”he wonders. “Is there a Disney effect — ‘Anything cuter than bunnies I will not neuro-control’ –, or should we base our judgments of cyborg projects on something else? Should we make an ethical distinction between forcing muscles to contract (as Maharbiz’s wing electrodes do) and simply rewarding an animal for moving the way we want (as Hermer’s brain electrodes do)? Or is it how we use the cyborgs that matters?
For his part, Maharbiz says he’s motivated more by the challenge of seeing what he can make insects do than by imagining how his work will ultimately be used. “Maybe I’m an example of a horrible amoral scientist,” he says, “but I think it would be fabulous to show, for example, that I could get a beetle to do a barrel roll, which it would never do in nature.” Everyone’s ethical barometer is set differently, and we won’t all welcome the notion of a barrel-rolling beetle. That’s fine with Maharbiz, who notes that most of us haven’t sat down and thought through what it means to take over an animal’s body, to physically force their muscles and minds to do our bidding. Why would we? Until recently, the idea seemed like pure science fiction. One of the ways his work can be useful, Maharbiz says, is “to get people to think about whether this is something we want to do.”
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Our options for mind manipulation are expanding as well. While Maharbiz and others are using electrodes and wires to physically force neurons to fire, some geneticists and neuroscientists are developing an alternative approach, engineering animals whose brains can be controlled with flashes of light. The technique, which comes from the hot, young field of optogenetics, relies on opsins, a class of light-sensitive molecules that bacteria, fungi and plants use to sense sunlight and convert it into energy. In 2005, scientists discovered that they could put opsin genes into mammalian brain cells using an unlikely assistant: a virus. Viruses are experts at delivering DNA; whenever they infect a cell, they dump their own genomes inside. In the early days of genetic engineering, biologists realized that they could get viruses to carry other genes into cells, too. In optogenetics, scientists insert an opsin gene into a virus, then inject the modified virus into the brain of a mouse. The virus infects the neurons, depositing the opsin DNA inside.
The mouse’s neurons begin to manufacture their own opsins and install them in their membranes, the thin, fatty layer that surrounds each cell. In the membrane, the opsins operate as light-sensitive channels; when scientists shine a light on the mouse’s brain, the opsin channels open and electrically charged particles rush into the cell. The influx changes the voltage inside the neuron. Different opsins respond to light in different ways — some usher positively charged particles into a neuron, making it more likely to fire. Others admit negatively charged particles, which suppress neural activity. By attaching a little snippet of regulatory DNA to the front of the opsin gene, researchers can make sure that only certain kinds of neurons produce the light-sensitive molecule. As a result, they can engineer a mouse’s brain so that one type of neuron, in one brain circuit or region, responds to a flash of light, while its neighbor is unaffected.
Equipped with this technology, we can make mice do the darnedest things. By turning certain neurons on and off, we can make rodents suddenly fall asleep or awaken. Or we can use a beam of light to activate a set of neurons involved in aggression, turning an otherwise calm mouse into a prizefighter who indiscriminately attacks other rodents — or even inanimate objects. These kinds of experiments hold huge promise for basic research; toggling a neural circuit on and off helps scientists puzzle out how those neurons affect behavior.
In 2011, Edward Boyden, a neuroscientist at MIT, used the tools of optogenetics to wirelessly direct mouse movements. Boyden’s team began with mice that had been modified to express opsins in certain neurons in the motor cortex; when exposed to light, these motor neurons would begin to fire. Then they constructed a mouse helmet — a headpiece that contained a radio antenna and an array of light-emitting diodes — and mounted it on one of their specially engineered mice. The scientists then sat back and used their wireless transmitter to flick the helmet’s lights on and off. When they turned all the lights on, a mouse that had been sitting calmly in its cage immediately began running around. (“It’s sort of turning up the volume knob of movement,” Boyden reports.) They also discovered that when they illuminated just one side of the helmet, a mouse would start spinning in that direction. (Unlike other optogenetics methods, the helmet is entirely noninvasive; the lights can activate neurons from the outside of the skull.)
Optogenetics gives us another way to bend animals to our will, but Boyden has no interest in using his wireless helmets to create a remote-controlled rodent army. To Boyden, the headset is an important breakthrough because it will expand the kinds of experiments that optogenetics researchers can do and pave the way for novel therapeutic devices. Many scientists in the field imagine implanting optical “prosthetics” in the human brain to treat neurological disorders with light. They dream of being able to selectively activate or deactivate neurons involved in Parkinson’s, epilepsy, sleep disorders, addiction and more. Setting animal brains ablaze is the first step toward that goal.
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Even as scientists come up with fancy new methods for commandeering animal brains, Greg Gage and Tim Marzullo, a pair of former neuroscience postdocs, are taking these techniques and making them available to anyone with an Internet connection and a hundred dollars to spare. As graduate students at the University of Michigan, the friends volunteered at local public schools, teaching students about human and animal brains. They were frustrated by the high barrier of entry to neuroscience, finding it odd that while anyone can pick up a telescope and look at the Moon, only advanced college students get the opportunity to see a neuron fire.
In 2009, Gage and Marzullo established Backyard Brains, a company that sells low-cost kits that will turn any interested amateur into a neuroscientist, if only for a day or two. (The company’s motto, emblazoned on its custom-made circuit boards, is “Neuro-science for Everyone!”) Their first product was a little contraption known as the SpikerBox. On sale for $99.98, the device lets customers observe neural firing in a cockroach in real time. (A set of three roaches is $12 extra.) The procedure is simple: Just insert two needlelike electrodes into a cockroach’s leg, and the SpikerBox will do the rest, amplifying the electrical activity of the insect’s neurons and transmitting it to an attached computer or smartphone as that characteristic visual pattern of peaks and valleys. The SpikerBox put Backyard Brains on the map, and instructors in 35 high schools and 100 universities have used the kits with their students.
For their second product, Gage and Marzullo decided to push the boundaries even further, to venture beyond brain observation and into brain control. Taking inspiration from the world of cyborg animals, they created a kit that provides their customers with all the tools they need to take over the nervous system of a living cockroach. In principle, the Backyard Brains RoboRoach is nearly indistinguishable from the beetles Maharbiz is making in a university lab — and that is precisely what is so remarkable about it. It means we can all experiment with bionic bugs in our own homes. Or, as it happens, in a crowded neighborhood coffee shop, which is precisely the plan when I meet Gage and Marzullo for breakfast in Woods Hole, Massachusetts.
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The bespectacled pair greet me at a popular local café, and we find ourselves some seats on the outdoor patio. Marzullo pulls out a plastic box of cockroaches and plops it down on our table. If you’re new to the hobby of animal mind manipulation, the cockroach is an excellent place to start. Because a roach relies on its long, fluid-filled antennae for a host of sensory and navigational functions, its nervous system is stunningly easy to hack; all a wannabe roach-master has to do is thread a wire inside each antenna. (“It’s like designed to be a cyborg,” Marzullo says.)
Marzullo has spent the morning prepping two roaches for their remote-controlled destiny. Several hours ago, he dropped the cockroaches into a miniature cooler of ice water — the preferred method, apparently, for anesthetizing insects. Then he pulled the roaches out of the cooler, their bodies motionless, their sensations dulled. (“We actually don’t know if insects feel pain,” Marzullo and Gage write on the Backyard Brains website, “but we do make the assumption that they do, which is why we anesthetize them in the first place.”) With a pair of everyday household scissors, Marzullo snipped the ends off each antenna. Then he slipped a thin silver wire inside. Thereafter, any electrical signals sent down the wires would be transferred directly to the roach’s nervous system.
Steering the roach simply requires taking advantage of a natural cockroach instinct: When one of the cockroach’s antennae detects an obstacle, the bug turns in the other direction. Zap the right antenna and the insect, convinced it’s about to bump into a wall on the right side of its body, will turn to the left. And vice versa. (The SUNY researchers had tapped into the same instinct in training their cyborg rats to turn away from perceived obstacles. But unlike the robo-rats, the cyborg cockroaches needed no special training or reinforcement to follow directional commands.)
Marzullo opens his bug box and removes one of the roaches. The wires run out of its antennae and into a small black box that Marzullo has glued onto its head. Marzullo plugs this “connector” into the cockroach backpack, a red-and-green assemblage of circuit boards. The electronics are slightly modified versions of circuit boards that come from a widely available toy: a plastic, remote-controlled inchworm called the HexBug that retails for twelve dollars at Toys“R”Us. When these circuit boards are linked to the head-mounted connector, Marzullo and Gage can use the remote control that comes with the toy to deliver pulses of electricity to the roach.
As Marzullo fiddles with the cockroach, he notices a family of three sitting at the table next to us. They’re all staring.
“What is it?”the father asks.
“The world’s first commercially available cyborg,” Marzullo says. “You want to do it, young lady?” he asks, handing the remote to the man’s 10-year-old daughter. He shows the girl which buttons to press.
We all head out to the sidewalk. The bug goes down. The little girl starts hitting buttons on the remote, steering the roach all around the sidewalk, while her father advises: “Don’t let it go into the street … Turn him into the shade.” The girl’s power to control the roach is, admittedly, crude. She can’t make the insect start or stop moving, and there’s no way to force it to simply move forward in a straight line. All she can do is let the roach do its roach thing, taking off in whatever direction its little invertebrate heart desires, and then overlay her own “left” or “right” commands, forcing the bug to turn and start moving in a different direction.
But even that small power is impressive, and a crowd forms.
People watch and smile, and Gage and Marzullo laugh and joke with the assembled audience. “There you go,” Marzullo says, “neuroscience for the people.”
“It looks so real!” a passing woman exclaims.
“It is real,” Gage says.“We’re selling these for 99 bucks.” The kit comes with all that customers need to make the cyborgs themselves — the circuit boards, the controller, the remote and detailed instructions for performing the insect surgery.
Then it’s my turn. I return to our table and pick up the second roach, which Marzullo has kindly prepared for me. Its sticky legs tickle my palm as I carry it out to the sidewalk. I place it down gingerly, and it begins to scuttle off. I fumble with the remote before finding the “L” button. I hit it, and the roach abruptly spins to the left. The effect is less dramatic after that, but convincing.
“It’s such a compelling demonstration,” Marzullo says. “We go to classrooms all the time and even the most jaded, problem kid in the room is going to pay attention to this. It doesn’t take very much time to break down their veneer when we bring out . . . remote- controlled bugs.”
Nevertheless, the RoboRoach has not been nearly as brisk a seller as Gage and Marzullo had hoped; as of June 2012, they’d squeaked out 51 sales. Perhaps that’s because it takes a special kind of customer to want to hijack another creature’s mind. “It’s kind of edgy,” Marzullo says. “It taps into human fears of puppet masters, that we are somehow evil scientists that don’t respect the natural order of things.” Gage and Marzullo have heard the same objections as other cyborg-animal scientists — that what they’re doing to animals is inhumane, disgusting and just plain wrong. They say they inspire more vitriol than scientists like Maharbiz, who are doing their research in official university laboratories. “We’re doing all this stuff on the fringe,” Marzullo says. “We’re not affiliated with any university, we go out in public and we’re pretty flamboyant about what we do.”
Gage and Marzullo attract controversy for the same reason that Alan Blake did as he prepared to bring GloFish to market — because they are taking biotechnology out of the lab and putting it into the hands of the public. And just like Blake, they are criticized for meddling with animal bodies for “trivial” purposes. Most people, Marzullo explains, have accepted the use of animals for scientific research, defense, or food. “But if you exploit animals for education,” he says, “people aren’t cool with that.” (“From my perspective,” he adds, “that’s the best use of animals. It’s an investment in the future.”)
Is educating students about the nervous system — and potentially encouraging a new generation of neuroscientists — a less-justifiable use of animals than hunting out mines or earthquake survivors? It’s time to start thinking through these issues, because now that the tools of brain control have been liberated from the lab, there’s no telling how they’ll be used.
Indeed, there is a growing community of “biohackers,” science enthusiasts who are experimenting with genes, brains and bodies outside the confines of traditional laboratories, working on shoestring budgets in their garages and attics, or joining the community labs that are springing up around the country. Some of these resourceful do-it-yourselfers are even building their own versions of high-tech laboratory equipment that normally costs thousands of dollars.
Backyard Brains is tapping into this movement, giving amateurs access to some of science’s most sophisticated tools and techniques (As it happens,their most recent product is a kit that allows customers to play around in the world of optogenetics, using blue light to make the muscles of transgenic fruit flies twitch.) And their customers are surprising them, in the best possible way, by coming up with ideas and discoveries of their own. A class of New York high school students working with the RoboRoach pinpointed a nerve that they could stimulate to make the insect walk straight ahead. Another customer — a Microsoft programmer — bought an EEG cap and tried to use his own brain waves to steer the roach. (It didn’t work, but he gets points for creativity.)
If these unprompted experiments are any indication, there are plenty of amateurs with an appetite for independent investigation and their own ideas for reengineering animals. Future generations are going to grow up tinkering not with computers, but with life itself. We already have the annual International Genetically Engineered Machine competition, in which high school and college students use standard genetic parts — easily available bits of DNA — to create cells with novel properties. In past years, teams have created bacteria that can clean heavy metal from polluted water, glow in a rainbow of colors, or give off the pleasant odor of banana or mint. We may one day have a similar competition that asks youngsters to engineer new kinds of animal-machine hybrids. Perhaps DARPA will even invite enthusiastic amateurs to respond to its scientific calls or look to the public for solutions to its most pressing problems.
The latest, greatest cyborg critters may come not from state-of-the-art labs, but the minds of curious kids and individual hobbyists. Though scientists will continue to build their cyborg animals, Maharbiz says he fully expects that “kids will be able to hack these things, like they wrote code in the Commodore 64 days.” We are heading toward a world in which anyone with a little time, money, and imagination can commandeer an animal’s brain. That’s as good a reason as any to start thinking about where we’d draw our ethical lines. The animal cyborgs are here, and we’ll each have to decide whether we want a turn at the controls.
DARPA’s call essentially launched a grand science fair, one designed to encourage innovation and tap into the competitive spirit of scientists around the country. The agency invited researchers to submit proposals outlining how they’d create steerable insect cyborgs and promised to fund the most promising projects. What the agency wanted was a remote-controlled bug that could be steered to within five meters of a target. Ultimately, the insects would also need to carry surveillance equipment, such as microphones, cameras or gas sensors, and to transmit whatever data they collected back to military officials. The pamphlet outlined one specific application for the robo-bugs — outfitted with chemical sensors, they could be used to detect traces of explosives in remote buildings or caves — and it’s easy to imagine other possible tasks for such cyborgs. Insect drones kitted out with video cameras could reveal whether a building is occupied and whether those inside are civilians or enemy combatants, while those with microphones could record sensitive conversations, becoming bugs that literally bugged you.
As far-fetched and improbable as DARPA’s dream of steerable robo-bugs sounds, a host of recent scientific breakthroughs means it’s likely to be far more successful than Acoustic Kitty was. The same advances that enabled the development of modern wildlife-tracking devices — the simultaneous decrease in size and increase in power of microprocessors, receivers and batteries — are making it possible to create true animal cyborgs. By implanting these micromachines into animals’ bodies and brains, we can seize control of their movements and behaviors. Genetics provides new options, too, with scientists engineering animals whose nervous systems are easy to manipulate. Together, these and other developments mean that we can make tiny flying cyborgs — and a whole lot more. Engineers, geneticists and neuroscientists are controlling animal minds in different ways and for different reasons, and their tools and techniques are becoming cheaper and easier for even us nonexperts to use. Before long, we may all be able to hijack animal bodies. The only question is whether we’ll want to.
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DARPA’s call for insect cyborgs piqued the interest of Michel Maharbiz, an electrical engineer at the University of California, Berkeley. He was excited by the challenge of creating flying machines that merged living bodies and brains with electronic bits and bytes. “What I wanted at the end of the day was a remote-controlled airplane,” Maharbiz recalls. “What was the closest thing to a remote-controlled airplane that I could get with these beetles?”
Maharbiz was an expert at making small electronic devices but an amateur when it came to entomology. So he started reading up. He figured that most scientists taking on DARPA’s challenge would work with flies or moths, longtime laboratory superstars, but Maharbiz came to believe that beetles were a better bet. Compared with flies and moths, beetles are sturdy animals, encased in hard shells, and many species are large enough to carry significant cargo. The downside: Scientists didn’t know much about the specific nerve pathways and brain circuits involved in beetle flight.
That meant that the first challenge was to unravel the insects’ biology. Maharbiz and his team began working with several different beetle species and eventually settled on Mecynorrhina torquata, or the flower beetle. It is a scary-looking bug — more than two inches long, with fearsome claws and a rhinoceros-like horn on the forehead. Through trial and error, the scientists homed in on a promising region of the beetle brain nestled at the base of the optic lobes. Previous research had shown that neural activity in this area helped keep the insect’s wings oscillating, and Maharbiz’s team discovered that when they stimulated this part of the brain in just the right way, they could start and stop beetle flight. When they sent a series of rapid electrical signals to the region, the beetle started flapping its wings and readied itself for takeoff. Sending a single long pulse to the same area prompted the insect to immediately still its wings. The effect was so dramatic that a beetle in mid-flight would simply fall out of the air.
After he discovered these tricks, Maharbiz was ready to try building the full flying machine. The flower beetle’s transformation began with a quick trip to the freezer. In the icy air, the beetle’s body temperature dropped, immobilizing and anesthetizing the insect. Then Maharbiz and his students removed the bug from the icebox and readied their instruments. They poked a needle through the beetle’s exoskeleton, making small holes directly over the brain and the base of the optic lobes, and threaded a thin steel wire into each hole.
They made another set of holes over the basalar muscles, which modulate wing thrust and are located on either side of the beetle’s body. The researchers pushed a wire into the right basalar muscle. Stimulating it would cause the beetle’s right wing to start beating with more power, making the insect veer left. They put another wire into the left basalar muscle; they would use it to steer the beetle to the right. The loose ends of all these wires snaked out of their respective holes and plugged into a package of electronics mounted with beeswax on the beetle’s back. This “backpack” included all the equipment Maharbiz needed to wirelessly send signals to the beetle’s brain: a miniature radio receiver, a custom-built circuit board, and a battery.
Then it was time for a test flight. One of Maharbiz’s students called up their custom-designed “Beetle Commander” software on a laptop. He issued the signal. The antennae jutting out of the beetle’s backpack received the message and passed it along to the circuit board, which sent electricity surging down the wire and into the beetle’s optic lobe. The insect’s wings began to flap. The empty white room the researchers used as an airfield filled with a buzzing sound, and the bug took flight. The beetle flew on its own — it didn’t need any further direction from human operators to stay airborne — but as it cruised across the room, the researchers overlaid their own commands. They pinged the basalar muscles, prompting the beetle to weave back and forth through the room, as if flying through an invisible maze. It wouldn’t have looked out of place going up against a stunt pilot at an air show. Another jolt of electricity to the optic lobe, and the beetle dropped out of the air and skittered across the tile floor.
As soon as Maharbiz presented his work, the news stories came fast and furious, with pronouncements such as, “The creation of a cyborg insect army has just taken a step closer to reality,” “Spies may soon be bugging conversations using actual insects, thanks to research funded by the U.S. military” and more. A columnist speculated about the possibility of a swarm of locust drones being used as vehicles for launching deadly germs. There was chatter about beetles that had been “zombified,” and references to “the impending robots vs. humans war.”
When Maharbiz reflects upon this media frenzy, he admits that the immense public interest in his work doesn’t surprise him. The research, after all, is practically primed to light up the futuristic-fantasy centers of our brains. Insects, even without modifications, seem like weird, alien organisms to many of us. As Maharbiz explains, “Insects have inherently some sort of strange, science fiction quality that a bunny doesn’t have.” Add in miniature electronics, flying devices, animal-machine hybrids, and covert military operations, and you have a recipe for dystopian daydreaming.
But Maharbiz bristles at the most sinister suggestions, at the media coverage that suggests his beetles are the product of, as he puts it, “some evil government conspiracy.” As for the possibility that the U.S. government is planning to use the bugs to build a killer insect army or to spy on its own citizens? “I think that’s nonsense,” he says. His beetles haven’t been sent out into the field yet — they still need some refinement before they’re ready for deployment — but if and when they are, Maharbiz says he expects his bugs to be used abroad in routine military operations. (Of course, some people may find that “equally reprehensible,” he acknowledges.) There are civilian applications, too. Imagine, Maharbiz tells me, an army of beetle-bots, steered to the scene of an earthquake. The bugs could be outfitted with temperature sensors, guided through rubble and programmed to send messages back to search teams if they detect any objects that are close to human body temperature; rescuers would then know exactly where to search for survivors.
Whatever the application, future insect commanders will have options that go beyond beetles. Maharbiz is working on a remote-controlled fly, which he anticipates being especially difficult to build. “The fly is so small and the muscles are so packed and everything’s so tiny,” he says, that even just implanting the electronics will be challenging. A Chinese research team has managed to start and stop flight in honeybees, and Amit Lal, the engineer who led the DARPA program, has created steerable cyborg moths.
One of Lal’s innovations has been figuring out how to take advantage of morphogenesis, the process by which many species of insects transform from wriggling larvae to spindly, multilegged adults. During pupation, a baby insect wraps itself in a protective cocoon or shell while its soft, immature body becomes a more structurally complex adult one. (Lal’s species of choice is the tobacco hawk moth, which morphs from a bright green worm into a brown-and-white spotted moth.) To Lal, this phase of the insect life cycle presented a unique opportunity; he hoped that if he inserted electronic components into a hawk moth when it was a wee pupa, the bug’s body would rebuild itself around the implant. In one set of experiments, Lal and his colleagues pushed thin wires through the hard shell that protects a hawk moth pupa and positioned them in the insect’s neck muscles and brain. Outside the bug’s body, the wires linked up with a small circuit board, which the researchers left resting loosely atop the pupal case. They repeated the procedure with 29 more pupae and then tucked them all away inside an incubator and allowed them to develop normally.
About a week later, the insects shed their shells, emerging as fully grown moths. Their bodies had in fact fashioned themselves around the implants; tissue had grown around the wires, securing them in place. The wires ran out of the moths’ heads and partway down their backs, winding their way into the attached circuit board. All researchers had to do to begin steering the moths was plug their control system into the circuit board, a task that took a matter of seconds.
These kinds of pupal surgeries have much to recommend them, the researchers say. They lead to more stable, permanent interfaces between electronic devices and living tissue. The approach may also be less traumatic for the animals; bugs heal easily during pupation, and since the adults are born with circuit boards hanging out of their backs, they’re less likely to perceive them as foreign objects or extra weight. (After all, the bugs will never know a life in which they aren’t attached to circuit boards.) It’s also much easier to operate on a pupa than an adult insect. The procedure is so simple that it could enable the “mass production of these hybrid insect-machine systems,” the scientists wrote.
Still, the robo-bugs aren’t quite ready for their tour of duty. Our directional control is still pretty crude. Ultimately, we’ll want to do more than make an insect simply veer left. We’ll want to be able to command it to turn, say, precisely 35 degrees to the left or navigate a complicated three-dimensional space, such as a chimney or pipe. There’s also the matter of the surveillance equipment. So far, the main focus has been on building insects that we can steer, but for these cyborgs to be useful, we’ll need to outfit them with various sensors and make sure that they can successfully collect and transmit environmental information. And though the cyborg insects power their own flight — something that completely robotic fliers cannot do — the surveillance equipment will need to get its electricity from somewhere.
One intriguing possibility is to use the insect’s own wings as a source of power. In 2011, a team of researchers from the University of Michigan announced that they had accomplished just that by building miniature generators out of ceramic and brass. Each tiny generator was a flattened spiral — imagine the head of a thumbtack, if it were shaped from a tight coil of metal rather than a single flat sheet — measuring 0.2 inches across. When they were mounted on the beetle’s thorax, these generators transformed the insect’s wing vibrations into electrical energy. With some refinement,the researchers note, these energy-harvesting devices could be used to power the equipment toted around by cyborg bugs.
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Insects could give us a cyborg-animal air force, zooming around the skies and searching for signs of danger. But for terrestrial missions, for our cyborg-animal army, we’d have to look elsewhere. We’d have to look to a lab at the State University of New York (SUNY) Downstate, where researchers have built a remote-controlled rat.
We’ve been rooting around in rat brains for ages; neuroscientists often send electrical signals directly into rodents’ skulls to elicit certain reactions and behaviors. Usually, however, this work requires hooking a rodent up to a system of cables, severely restricting its movement. When the SUNY team, led by the neuroscientist John Chapin, began their work more than a decade ago, they wanted to create something different — a method for delivering these electrical pulses wirelessly. They hoped that such a system would free researchers (and rats) from a cumbersome experimental setup and enable all sorts of new scientific feats. A wireless system would allow scientists to manipulate a rat’s movements and behaviors while it was roaming freely and give us a robo-rodent suitable for all sorts of special operations. Rats have an excellent sense of smell, so cyborg rats could be trained to detect the scent of explosives, for instance, and then steered to a field suspected to contain land mines. (The task would pose no danger to the animals, which are too light to set off mines.) Or they could be directed into collapsed buildings and tasked with sniffing out humans trapped beneath the rubble, performing a job similar to the one Maharbiz imagines for his cyborg insects. “They could fit through crawl spaces that a bloodhound never could,” says Linda Hermer-Vazquez, a neuroscientist who was part of the SUNY team at the time.
But before any of that could happen, the SUNY scientists had to figure out how to build this kind of robo-rat. They began by opening up a rat’s skull and implanting steel wires in its brain. The wires ran from the brain out through a large hole in the skull, and into a backpack harnessed to the rodent. (“Backpack” seems to be a favorite euphemism among the cyborg-animal crowd.) This rat pack, as it were, contained a suite of electronics, including a microprocessor and a receiver capable of picking up distant signals. Chapin or one of his colleagues could sit five hundred yards away from the rat and use a laptop to transmit a message to the receiver, which relayed the signal to the microprocessor, which sent an electric charge down the wires and into the rat’s brain.
To direct the animal’s movements, the scientists implanted electrodes in the somatosensory cortex, the brain region that processes touch sensations. Zapping one area of the cortex made the rat feel as though the left side of its face was being touched. Stimulating a different part of the cortex produced the same phantom feeling on the right side of the rat’s face. The goal was to teach the rodent to turn in the opposite direction of the sensation. (Though that seems counterintuitive, it actually works with the rat’s natural instincts. To a rodent, a sensation on the right side of the face indicates the presence of an obstacle and prompts the animal to scurry away from it.)
During the training process, the SUNY scientists used an unconventional system of reinforcement. When the rat turned in the correct direction, the researchers used a third wire to send an electrical pulse into what’s known as the medial forebrain bundle (MFB), a region of the brain involved in processing pleasure. Studies in humans and other animals have shown that direct activation of the MFB just plain feels good. (When the scientists gave the rats the chance to stimulate their own MFBs by pressing down on a lever, the animals did so furiously — hitting the lever as many as 200 times in 20 minutes.) So sending a jolt of electricity zinging down to a rat’s MFB acted as a virtual reward for good behavior. Over the course of 10 sessions, the robo-rats learned to respond to the cues and rewards being piped into their brains. Scientists managed to direct the rodents through a challenging obstacle course, coaxing them to climb a ladder, traverse a narrow plank, scramble down a flight of stairs, squirm through a hoop and then navigate their way down a steep ramp.
As a final demonstration, the researchers simulated the kind of search-and-rescue task a robo-rat might be asked to perform in the real world. They rubbed tissues against their forearms and taught the rodents to identify this human odor. They constructed a small Plexiglas arena, filled it with a thick layer of sawdust, and buried human-scented tissues inside. When they released the robo-rats into the arena, the animals tracked down the tissues in less than a minute. The scientists also discovered that the rats that received MFB rewards found the target odors faster and dug for them more energetically than rodents that had been trained with conventional food rewards. As Hermer-Vazquez recalls: “The robo-rats were incredibly motivated and very accurate.”
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Whether it’s rescue rat-bots or bomb-sniffing beetle drones, electronics are helping us create new beasts of burden, allowing us to conscript creatures into the modern animal workforce. These are no mere donkeys, poked and prodded into carrying our bags up steep hills; these animals’ brains are being taken hostage, their nervous systems forced to cooperate with our plans. As Maharbiz wrote in an account of his research, “[W]e wanted to be sure we could deliver signals directly into the insect’s own neuromuscular circuitry, so that even if the insect attempted to do something else, we could provide a countercommand. Any insect that could ignore our commands would make for a crummy robot.”
Is it wrong to take the reins of another creature’s nervous system? It certainly feels wrong. When we dictate the movements of sentient beings, we turn them into mere machines, no different than those remote-controlled airplanes Maharbiz was trying to emulate. Many animal liberationists and philosophers have argued that one of our obligations to animals is “noninterference” — that animals have the right to be the leaders of their own lives and that we have a duty to leave them alone. Cyborg animals represent an extreme violation of that responsibility. And unlike in wildlife tracking projects, in which our meddling may help save species, deploying cyborg insects and rodents on the battlefield isn’t going to do much to benefit animals.
The trouble is that we have to balance this intrusion into the life of another living being against the good that animal-machine mash-ups could do. It’s possible to care about animals and want to spare them needless suffering, and yet also decide that sometimes human welfare (say, the life of an American soldier) comes first. In fact, most Americans take this view, according to the psychologist Harold Herzog, who specializes in untangling our relationships with other species. After all, if you insist that an animal’s life is worth exactly the same as a human one, no matter what, Herzog says, “you can end up at untenable places.” (Such as deciding that you should flip a coin to decide whether to save a puppy or a child from a burning building.) Herzog has found that our attitudes toward other species are nuanced, complicated and often inconsistent. It’s not unusual, he says, to wish we could do without animal experimentation but still be grateful for the lifesaving drugs and treatments such research has made possible. It’s not strange to wish scientists would stop squirting shampoo into rabbits’ eyes and simultaneously want them to use as many bunnies as they need to find a cure for cancer.
Unless we rule out all use of animals for human purposes, we have to evaluate each application on a case-by-case basis, weighing pain against gain. In the case of the robo-beasts, the animals are anesthetized when the electronics are implanted in their bodies, but recovering from surgery isn’t painless. The devices themselves may cause stress, and being piloted around a lab by an ambitious postdoc can’t be any great picnic. But the price that animals have to pay for this research is relatively small. (Maharbiz notes that his beetles had normal lifespans — which, in insects, is a none-too-impressive several months — and “flew, ate, and mated just like regular beetles.”) Remotely guided rats aren’t exactly a cure for cancer, but if they can hunt down mines or find earthquake victims trapped in rubble, they could certainly save human lives. So while the cyborg research can seem creepy, I’m glad that there are scientists out there who are doing it.
The details matter, however. I wouldn’t be so keen on the research if the cost to animals were greater — if, say, each electric jolt we sent to an animal’s brain caused excruciating pain. Nor would I want to see robo-rats used to string lights along the branches of Christmas trees — an actual suggestion the SUNY researchers made in their patent application. There’s a species effect in play, too. I have no special affection for insects or rodents, and I’d find it a lot harder to sanction the creation of robo-dogs or robo-bonobos. Maharbiz has noticed this inconsistency, too, though it’s not clear where that leaves us, ethically speaking. “Where do you draw the line?”he wonders. “Is there a Disney effect — ‘Anything cuter than bunnies I will not neuro-control’ –, or should we base our judgments of cyborg projects on something else? Should we make an ethical distinction between forcing muscles to contract (as Maharbiz’s wing electrodes do) and simply rewarding an animal for moving the way we want (as Hermer’s brain electrodes do)? Or is it how we use the cyborgs that matters?
For his part, Maharbiz says he’s motivated more by the challenge of seeing what he can make insects do than by imagining how his work will ultimately be used. “Maybe I’m an example of a horrible amoral scientist,” he says, “but I think it would be fabulous to show, for example, that I could get a beetle to do a barrel roll, which it would never do in nature.” Everyone’s ethical barometer is set differently, and we won’t all welcome the notion of a barrel-rolling beetle. That’s fine with Maharbiz, who notes that most of us haven’t sat down and thought through what it means to take over an animal’s body, to physically force their muscles and minds to do our bidding. Why would we? Until recently, the idea seemed like pure science fiction. One of the ways his work can be useful, Maharbiz says, is “to get people to think about whether this is something we want to do.”
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Our options for mind manipulation are expanding as well. While Maharbiz and others are using electrodes and wires to physically force neurons to fire, some geneticists and neuroscientists are developing an alternative approach, engineering animals whose brains can be controlled with flashes of light. The technique, which comes from the hot, young field of optogenetics, relies on opsins, a class of light-sensitive molecules that bacteria, fungi and plants use to sense sunlight and convert it into energy. In 2005, scientists discovered that they could put opsin genes into mammalian brain cells using an unlikely assistant: a virus. Viruses are experts at delivering DNA; whenever they infect a cell, they dump their own genomes inside. In the early days of genetic engineering, biologists realized that they could get viruses to carry other genes into cells, too. In optogenetics, scientists insert an opsin gene into a virus, then inject the modified virus into the brain of a mouse. The virus infects the neurons, depositing the opsin DNA inside.
The mouse’s neurons begin to manufacture their own opsins and install them in their membranes, the thin, fatty layer that surrounds each cell. In the membrane, the opsins operate as light-sensitive channels; when scientists shine a light on the mouse’s brain, the opsin channels open and electrically charged particles rush into the cell. The influx changes the voltage inside the neuron. Different opsins respond to light in different ways — some usher positively charged particles into a neuron, making it more likely to fire. Others admit negatively charged particles, which suppress neural activity. By attaching a little snippet of regulatory DNA to the front of the opsin gene, researchers can make sure that only certain kinds of neurons produce the light-sensitive molecule. As a result, they can engineer a mouse’s brain so that one type of neuron, in one brain circuit or region, responds to a flash of light, while its neighbor is unaffected.
Equipped with this technology, we can make mice do the darnedest things. By turning certain neurons on and off, we can make rodents suddenly fall asleep or awaken. Or we can use a beam of light to activate a set of neurons involved in aggression, turning an otherwise calm mouse into a prizefighter who indiscriminately attacks other rodents — or even inanimate objects. These kinds of experiments hold huge promise for basic research; toggling a neural circuit on and off helps scientists puzzle out how those neurons affect behavior.
In 2011, Edward Boyden, a neuroscientist at MIT, used the tools of optogenetics to wirelessly direct mouse movements. Boyden’s team began with mice that had been modified to express opsins in certain neurons in the motor cortex; when exposed to light, these motor neurons would begin to fire. Then they constructed a mouse helmet — a headpiece that contained a radio antenna and an array of light-emitting diodes — and mounted it on one of their specially engineered mice. The scientists then sat back and used their wireless transmitter to flick the helmet’s lights on and off. When they turned all the lights on, a mouse that had been sitting calmly in its cage immediately began running around. (“It’s sort of turning up the volume knob of movement,” Boyden reports.) They also discovered that when they illuminated just one side of the helmet, a mouse would start spinning in that direction. (Unlike other optogenetics methods, the helmet is entirely noninvasive; the lights can activate neurons from the outside of the skull.)
Optogenetics gives us another way to bend animals to our will, but Boyden has no interest in using his wireless helmets to create a remote-controlled rodent army. To Boyden, the headset is an important breakthrough because it will expand the kinds of experiments that optogenetics researchers can do and pave the way for novel therapeutic devices. Many scientists in the field imagine implanting optical “prosthetics” in the human brain to treat neurological disorders with light. They dream of being able to selectively activate or deactivate neurons involved in Parkinson’s, epilepsy, sleep disorders, addiction and more. Setting animal brains ablaze is the first step toward that goal.
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Even as scientists come up with fancy new methods for commandeering animal brains, Greg Gage and Tim Marzullo, a pair of former neuroscience postdocs, are taking these techniques and making them available to anyone with an Internet connection and a hundred dollars to spare. As graduate students at the University of Michigan, the friends volunteered at local public schools, teaching students about human and animal brains. They were frustrated by the high barrier of entry to neuroscience, finding it odd that while anyone can pick up a telescope and look at the Moon, only advanced college students get the opportunity to see a neuron fire.
In 2009, Gage and Marzullo established Backyard Brains, a company that sells low-cost kits that will turn any interested amateur into a neuroscientist, if only for a day or two. (The company’s motto, emblazoned on its custom-made circuit boards, is “Neuro-science for Everyone!”) Their first product was a little contraption known as the SpikerBox. On sale for $99.98, the device lets customers observe neural firing in a cockroach in real time. (A set of three roaches is $12 extra.) The procedure is simple: Just insert two needlelike electrodes into a cockroach’s leg, and the SpikerBox will do the rest, amplifying the electrical activity of the insect’s neurons and transmitting it to an attached computer or smartphone as that characteristic visual pattern of peaks and valleys. The SpikerBox put Backyard Brains on the map, and instructors in 35 high schools and 100 universities have used the kits with their students.
For their second product, Gage and Marzullo decided to push the boundaries even further, to venture beyond brain observation and into brain control. Taking inspiration from the world of cyborg animals, they created a kit that provides their customers with all the tools they need to take over the nervous system of a living cockroach. In principle, the Backyard Brains RoboRoach is nearly indistinguishable from the beetles Maharbiz is making in a university lab — and that is precisely what is so remarkable about it. It means we can all experiment with bionic bugs in our own homes. Or, as it happens, in a crowded neighborhood coffee shop, which is precisely the plan when I meet Gage and Marzullo for breakfast in Woods Hole, Massachusetts.
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The bespectacled pair greet me at a popular local café, and we find ourselves some seats on the outdoor patio. Marzullo pulls out a plastic box of cockroaches and plops it down on our table. If you’re new to the hobby of animal mind manipulation, the cockroach is an excellent place to start. Because a roach relies on its long, fluid-filled antennae for a host of sensory and navigational functions, its nervous system is stunningly easy to hack; all a wannabe roach-master has to do is thread a wire inside each antenna. (“It’s like designed to be a cyborg,” Marzullo says.)
Marzullo has spent the morning prepping two roaches for their remote-controlled destiny. Several hours ago, he dropped the cockroaches into a miniature cooler of ice water — the preferred method, apparently, for anesthetizing insects. Then he pulled the roaches out of the cooler, their bodies motionless, their sensations dulled. (“We actually don’t know if insects feel pain,” Marzullo and Gage write on the Backyard Brains website, “but we do make the assumption that they do, which is why we anesthetize them in the first place.”) With a pair of everyday household scissors, Marzullo snipped the ends off each antenna. Then he slipped a thin silver wire inside. Thereafter, any electrical signals sent down the wires would be transferred directly to the roach’s nervous system.
Steering the roach simply requires taking advantage of a natural cockroach instinct: When one of the cockroach’s antennae detects an obstacle, the bug turns in the other direction. Zap the right antenna and the insect, convinced it’s about to bump into a wall on the right side of its body, will turn to the left. And vice versa. (The SUNY researchers had tapped into the same instinct in training their cyborg rats to turn away from perceived obstacles. But unlike the robo-rats, the cyborg cockroaches needed no special training or reinforcement to follow directional commands.)
Marzullo opens his bug box and removes one of the roaches. The wires run out of its antennae and into a small black box that Marzullo has glued onto its head. Marzullo plugs this “connector” into the cockroach backpack, a red-and-green assemblage of circuit boards. The electronics are slightly modified versions of circuit boards that come from a widely available toy: a plastic, remote-controlled inchworm called the HexBug that retails for twelve dollars at Toys“R”Us. When these circuit boards are linked to the head-mounted connector, Marzullo and Gage can use the remote control that comes with the toy to deliver pulses of electricity to the roach.
As Marzullo fiddles with the cockroach, he notices a family of three sitting at the table next to us. They’re all staring.
“What is it?”the father asks.
“The world’s first commercially available cyborg,” Marzullo says. “You want to do it, young lady?” he asks, handing the remote to the man’s 10-year-old daughter. He shows the girl which buttons to press.
We all head out to the sidewalk. The bug goes down. The little girl starts hitting buttons on the remote, steering the roach all around the sidewalk, while her father advises: “Don’t let it go into the street … Turn him into the shade.” The girl’s power to control the roach is, admittedly, crude. She can’t make the insect start or stop moving, and there’s no way to force it to simply move forward in a straight line. All she can do is let the roach do its roach thing, taking off in whatever direction its little invertebrate heart desires, and then overlay her own “left” or “right” commands, forcing the bug to turn and start moving in a different direction.
But even that small power is impressive, and a crowd forms.
People watch and smile, and Gage and Marzullo laugh and joke with the assembled audience. “There you go,” Marzullo says, “neuroscience for the people.”
“It looks so real!” a passing woman exclaims.
“It is real,” Gage says.“We’re selling these for 99 bucks.” The kit comes with all that customers need to make the cyborgs themselves — the circuit boards, the controller, the remote and detailed instructions for performing the insect surgery.
Then it’s my turn. I return to our table and pick up the second roach, which Marzullo has kindly prepared for me. Its sticky legs tickle my palm as I carry it out to the sidewalk. I place it down gingerly, and it begins to scuttle off. I fumble with the remote before finding the “L” button. I hit it, and the roach abruptly spins to the left. The effect is less dramatic after that, but convincing.
“It’s such a compelling demonstration,” Marzullo says. “We go to classrooms all the time and even the most jaded, problem kid in the room is going to pay attention to this. It doesn’t take very much time to break down their veneer when we bring out . . . remote- controlled bugs.”
Nevertheless, the RoboRoach has not been nearly as brisk a seller as Gage and Marzullo had hoped; as of June 2012, they’d squeaked out 51 sales. Perhaps that’s because it takes a special kind of customer to want to hijack another creature’s mind. “It’s kind of edgy,” Marzullo says. “It taps into human fears of puppet masters, that we are somehow evil scientists that don’t respect the natural order of things.” Gage and Marzullo have heard the same objections as other cyborg-animal scientists — that what they’re doing to animals is inhumane, disgusting and just plain wrong. They say they inspire more vitriol than scientists like Maharbiz, who are doing their research in official university laboratories. “We’re doing all this stuff on the fringe,” Marzullo says. “We’re not affiliated with any university, we go out in public and we’re pretty flamboyant about what we do.”
Gage and Marzullo attract controversy for the same reason that Alan Blake did as he prepared to bring GloFish to market — because they are taking biotechnology out of the lab and putting it into the hands of the public. And just like Blake, they are criticized for meddling with animal bodies for “trivial” purposes. Most people, Marzullo explains, have accepted the use of animals for scientific research, defense, or food. “But if you exploit animals for education,” he says, “people aren’t cool with that.” (“From my perspective,” he adds, “that’s the best use of animals. It’s an investment in the future.”)
Is educating students about the nervous system — and potentially encouraging a new generation of neuroscientists — a less-justifiable use of animals than hunting out mines or earthquake survivors? It’s time to start thinking through these issues, because now that the tools of brain control have been liberated from the lab, there’s no telling how they’ll be used.
Indeed, there is a growing community of “biohackers,” science enthusiasts who are experimenting with genes, brains and bodies outside the confines of traditional laboratories, working on shoestring budgets in their garages and attics, or joining the community labs that are springing up around the country. Some of these resourceful do-it-yourselfers are even building their own versions of high-tech laboratory equipment that normally costs thousands of dollars.
Backyard Brains is tapping into this movement, giving amateurs access to some of science’s most sophisticated tools and techniques (As it happens,their most recent product is a kit that allows customers to play around in the world of optogenetics, using blue light to make the muscles of transgenic fruit flies twitch.) And their customers are surprising them, in the best possible way, by coming up with ideas and discoveries of their own. A class of New York high school students working with the RoboRoach pinpointed a nerve that they could stimulate to make the insect walk straight ahead. Another customer — a Microsoft programmer — bought an EEG cap and tried to use his own brain waves to steer the roach. (It didn’t work, but he gets points for creativity.)
If these unprompted experiments are any indication, there are plenty of amateurs with an appetite for independent investigation and their own ideas for reengineering animals. Future generations are going to grow up tinkering not with computers, but with life itself. We already have the annual International Genetically Engineered Machine competition, in which high school and college students use standard genetic parts — easily available bits of DNA — to create cells with novel properties. In past years, teams have created bacteria that can clean heavy metal from polluted water, glow in a rainbow of colors, or give off the pleasant odor of banana or mint. We may one day have a similar competition that asks youngsters to engineer new kinds of animal-machine hybrids. Perhaps DARPA will even invite enthusiastic amateurs to respond to its scientific calls or look to the public for solutions to its most pressing problems.
The latest, greatest cyborg critters may come not from state-of-the-art labs, but the minds of curious kids and individual hobbyists. Though scientists will continue to build their cyborg animals, Maharbiz says he fully expects that “kids will be able to hack these things, like they wrote code in the Commodore 64 days.” We are heading toward a world in which anyone with a little time, money, and imagination can commandeer an animal’s brain. That’s as good a reason as any to start thinking about where we’d draw our ethical lines. The animal cyborgs are here, and we’ll each have to decide whether we want a turn at the controls.
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