English Project

Name: Zafer Surname: Çepnioğlu School Number: 339 Class: 11/B Topic: Science/Biology Contents: Technology Alliances Are Making Researches To Store Data in DNA ...............2 Your Hidden Censor: What Your Mind Will Not Let You See ............................3 Lessons in Music Has A Good Effect On Aging Brain .........................................9 Parasites Are Going Extinct. Here's Why We Need To Save Them ...................13

Technology Alliances Are Making Researches To Store Data in DNA According to the market-analysis firm IDC, the digital universe could add some 175 zettabytes of data per year by 2025. That’s 175 with 21 zeroes after it. That amount of information will require massive data centers and vast energy resources to maintain. A small but growing group of researchers are suggesting DNA as a sustainable, stable replacement. These efforts got a lift last November, when a coalition of computing and biotech firms including Microsoft, Twist Bioscience, Illumina and Western Digital announced that they were forming the DNA Data Storage Alliance (DDSA). The alliance hopes to “organize the industry and think of how to build the whole ecosystem for DNA data storage”, says Xavier Godron, chief technology officer at DNA Script, a Paris-based developer of bench-top DNA synthesizers and a member of the alliance. Karin Strauss, a researcher at Microsoft in Redmond, Washington, says the DDSA formed in response to the “critical mass and community” coalescing around the technology, which until recently was largely theoretical. “It sounded like science fiction five years ago. It’s really starting to happen,” she says. The process of DNA data storage combines DNA synthesis, DNA sequencing and an encoding and decoding algorithm to pack information into DNA more durably and at higher density than is possible in conventional media. That could be up to 17 exabytes per gram. In a demonstration of the technology last October, geneticist George Church at Harvard Medical School in Boston, Massachusetts, and his team described a way to encode a snippet of music from the video game Super Mario Bros in the transitions between runs of identical

synthetic genetic bases, and then retrieve it and play it back on a computer. Olgica Milenkovic at the University of Illinois at Urbana-Champaign and her team have developed a ‘DNA punch card’ strategy that encodes data in nicks made in the DNA backbone; they used the technique to store a copy of former US president Abraham Lincoln’s Gettysburg address and an image of the Lincoln Memorial. And Robert Grass at the Swiss Federal Institute of Technology in Zurich and his team have devised a strategy for embedding digital genetic information — instructions for 3D printing an object, for instance — into the object itself, an approach they call “DNA-of-things”. The low-hanging fruit for DNA data storage is what Twist Bioscience chief executive Emily Leproust in San Francisco, California, calls ‘cold data’ — data that are written once and read rarely, if ever. That’s because DNA remains stable for a long time, but data access — through sequencing and data analysis — is slow. DNA has already proved itself to be up to the task of big data, albeit not in peer-reviewed publications. The DNA-storage firm Catalog in Boston, Massachusetts, another alliance member, announced in 2019 that it had used its DNA-writing technology to encode all of English-language Wikipedia into genetic material. And last year, Twist announced that it had stored an episode of the Netflix series Biohackers. Others see broader opportunities, and Church, for one, encourages researchers to think outside the box. Imagine fruit flies that can record video of everything they see in their DNA, or human tissues capable of storing physiological data. “If you have a new revolution, it’s usually misguided to try to apply it to the old way of thinking,” he says. Fact: DNA stands for deoxyribonucleic Acid Your Hidden Censor: What Your Mind Will Not Let You See Scientists probe the biases of “unconscious selective attention” It was a summer evening when Tony Cornell tried to make the residents of Cambridge, England see a ghost. He got dressed up in a sheet and walked through a public park waving his arms about. Meanwhile his assistants observed the bystanders for any hint that they

noticed something strange. No, this wasn’t Candid Camera. Cornell was a researcher interested in the paranormal. The idea was first to get people to notice the spectacle, and then see how they understood what their eyes were telling them. Would they see the apparition as a genuine ghost or as something more mundane, like a bloke in a bed sheet? The plan was foiled when not a single bystander so much as raised an eye brow. Several cows did notice, however, and they followed Cornell on his ghostly rambles. Was it just a fluke, or did people “not want to see” the besheeted man, as Cornell concluded in his 1959 report? Okay, that stunt was not a very good experiment, but twenty years later the eminent psychologist Ulric Neisser did a better job. He filmed a video of two teams of students passing a basketball back and forth, and superimposed another video of a girl with an umbrella walking right through the center of the screen. When he asked subjects in his study to count the number of times the ball was passed, an astonishing 79 percent failed to notice the girl with the umbrella. In the years since, hundreds of studies have backed up the idea that when attention is occupied with one thing, people often fail to notice other things right before their eyes. When you first learn about these studies, they seem deeply strange. Is it really possible that we are constantly failing to notice things right in front of us? Is there some mysterious force screening what we see and what remains hidden? According to Neisser the answer is yes, we

are constantly overlooking much of the world around us and no, there is nothing mysterious about it. The key is to realize that this is just what attention is: selectivity. For a brain with finite computing power, zooming in to focus on one thing always means picking up less information about everything else. That’s how we are able to concentrate on anything at all and leave behind the blooming, buzzing bundle of distraction that is the rest of the world. It is also why being absorbed in a basketball game renders us blissfully oblivious to all requests to take out the garbage. Prioritizing one thing and neglecting everything else are two sides of the same coin. Simple selectivity cannot be the end of the story, though, because recent research suggests that we miss some unattended things more than others. That’s right – the brain is selectively selective. In new research my colleagues Jazmin Brown-Iannuzzi, Sophie Trawalter, Kelly Hoffman and I pushed the idea of selective selectivity further by asking whether the unconscious screener might have priorities of its own. Scads of studies have suggested that the unconscious mind is riddled with stereotypes and biases, even among people who are consciously well intentioned. We asked whether the unconscious screener is prejudiced. We started with a video of two teams passing basketballs around, as in Neisser’s early study. Then we superimposed a video of a young black man or a young white man walking across the screen. Would there be a racial disparity in which man gets noticed? We predicted that it would depend on the kind of goals the study’s participants had in mind. For decades, social scientists have known that prejudices show a social distance effect: people are more approving of stereotyped groups at a cold, impersonal distance than when they are up close and personal. For instance, polls show that whites are more likely to support equality for black Americans at a distance (such as saying that they support integrated neighborhoods and workplaces) than to support close personal ties (such as saying that they approve of someone in their family having an inter-racial marriage). Although attitudes toward all of these topics have become steadily less prejudiced since the 1960’s, the gap between close and far social distances has remained remarkably constant. We told groups of white women that in a few minutes they would be asked to look through some online profiles of men to pick the best match for one of several roles. Two groups were to look for a socially distant match (a neighbor or a co-worker) and two would look for a more intimate match (a friend or a date). A separate control group was not told anything about searching profiles at all. After they understood what they were going to look for, we interrupted the study to say that first they had to complete a concentration test to make sure they were paying attention. The concentration task was —you guessed it — the ball tossing video, and the participants were asked to keep their eyes on the ball. The real question was whether the women would be more likely to see the white man when they on the lookout for a close connection. About two thirds of the women never saw the man walk across the screen in front of them, similar to the previous studies. As we suspected, who they saw depended on what they had on their minds. When the women were set to look for a suitable neighbor or co-worker, they saw the black man and the white man equally often. But when they were looking for a friend

or a date, they noticed the white man more than twice as often as the black man. The unconscious screener seemed to have racial preferences, but there was not a simple bias to see only whites or only blacks. The women were unconsciously deciding whether the man in the video was the kind of guy they were looking for. If not, he was never consciously perceived. The simple fact of selectivity has big consequences: at any moment we are aware of just a tiny fragment of all that is around us. Consider your visual experience right now. There is usually no experience of a line in your periphery where your vision stops; there’s just a fading out of what you notice. You can move your eyes around to find the edges, of course, but you normally don’t notice the absence. If you look down, even your nose seems to get out of your way: a half-transparent thing that you almost never see without a mirror despite that it is in plain sight from your eye sockets. Some psychologists and philosophers think that the rich and detailed conscious experience of the world around us is a grand illusion. The refrigerator light always appears to be on because when it is dark, we aren’t looking. Just so, our conscious experience seems to be a rich and detailed picture of the world because where it’s not, we aren’t paying attention.

The idea of selective selectivity means that the unconscious mind may be shaping our experience even more dynamically than previously thought, screening what we see based on goals and emotions. Scientists are only starting to understand how selective selectivity works. Consider what happens when each of your eyes sees something different. That doesn’t happen in daily life, but in the laboratory, scientists use a special kind of goggles that project images to each eye independently. One eye sees a face, say, and the other sees an elephant. Do you experience two pictures simultaneously, or a mixed-up face with an elephant trunk? Neither: conscious experience toggles back and forth between a face one moment and an elephant the next. The unconscious screener is fickle, but decisive. Psychologists Georg Alpers and Paul Pauli recently tested whether some kinds of pictures are more likely to be seen than others. On some trials of their experiment, one eye saw a neutral picture like a lamp, and the other eye saw a bloody scene of violence. On other trials, one eye saw a neutral picture and the other saw an erotic nude picture. The subjects’ conscious experiences of the pictures flipped back and forth, but the scenes of sex and violence were more likely to be the first ones seen, and they occupied consciousness much longer than the boring neutral images. Several studies have now confirmed that dangerous things like snakes, angry men, and snarling dogs can break through our concentration and intrude on consciousness. Dirty words and naughty pictures have the same effects. (I imagine it took a lot of delicate conversations between professors and the university ethics boards to produce this knowledge.) The common thread seems to be emotion. If it gets your heart racing it will get your attention. This makes good evolutionary sense. It is important to be selective so that the mind can devote most of its resources to the task at hand. But it is also useful to keep an eye or an ear out for the unexpected (especially if it might eat you or you might mate with it). One minute you are sitting at a sidewalk cafe happily immersed in your newspaper and espresso. The whooshing traffic and the singing birds and the panting joggers all fade away as you lose yourself in the latest political battle between your favorite party and the irrational maniacs who disagree with them. And then a sexy jogger with a snarling pit bull saunters by. Who can concentrate on politics? More to the point, who decided that this particular jogger gets to dominate your consciousness but the previous five were consigned to invisibility? It couldn’t be the conscious “you” who decided, because by the time you became aware of the jogger, the decision had already been made. There must be some part of the mind that is triaging the sights and sounds, but based on what, exactly? Critics of this research suggest that it may be driven by something other than emotion. In one early study that flashed pictures of religious symbols to each eye, Catholic subjects were more likely to see a Crucifix and Jewish subjects were more likely to see a Star of David. Critics argued that this difference was not about personal significance, but simply the fact that Catholics had seen more Crucifixes and Jews had seen more Stars of David, which made them easier to process. Is there something about the red of blood or the anatomy of a nude body that that sets off unconscious alarms irrespective of emotional significance?

Psychologist Emily Balcetis and colleagues tackled this problem by holding the pictures constant and changing how much they meant to people. One group of subjects in the study was told that they could earn extra chances in a lottery for each letter they could identify in their goggles. Another group earned extra chances for each number. Pictures of letters and numbers were flashed to each eye so quickly that there was only time to see one or the other. When it paid to see a number, people saw a number. When it paid to see a letter, they saw a letter. Scientists have argued for decades about how smart the screener is. Some believe it is a simpleton, able to detect basic sensory characteristics like light, color, and motion, but not able to read words for meaning or recognize what a picture is. If this view is right, it would be easy to break the screener down into simpler parts and understand it because it would be doing nothing more sophisticated than your digital camera. But the simpleton hypothesis cannot explain selective selectivity. It cannot explain why some events become visible or invisible based on what they mean to you. This trick requires a smarter screener. The question is how smart does the screener need to be to explain these findings? No scientist today believes in a Freudian unconscious, complete with its own quirks and urges, scheming to delude the conscious mind. The unconscious today is understood as a vast store of knowledge, habits, and associations that help process information efficiently rather than waiting in the queue for slower conscious thinking. To explain selective selectivity, the unconscious screener must be able to do at least two things. First, it has to know what the goal is. Second, it must make a first approximation of whether the candidate for consciousness fits the goal or not. This simple two-step comparison can explain why emotional events like dangerous and sexy things break through, because goals as basic as having sex and not being eaten are always relevant. It is not yet clear how sophisticated the screener can be. Our findings of racial bias, however, suggest something new about the assumptions the unconscious makes. At a minimum, our findings imply that the unconscious can represent social goals such as looking for a friend, a date, or a co-worker. And it seems to have opinions about which kind of people are suitable for each. These kinds of distinctions are more sophisticated, and perhaps more disturbing, than we had assumed. There is something particularly disquieting about this brand of bias, because there is a power asymmetry. The unconscious screener shapes what the conscious “you” gets to see, but the conscious “you” doesn’t have veto power over that decision. Of course, you could try to shift your attention or change your goals once you are aware of them, but by then it may be too late. The unconscious always has a head start. Personal contact between people of different races has always been seen as a powerful way to reduce prejudice. As the world becomes increasingly multicultural and globalized, these unconscious blinders might make us immune to that diversity. We cannot get to know or learn from people if we look right through them. The modern world might magnify these effects in a second way, because the power of the unconscious is greatest when our attention

is under the heaviest demands. In today’s multitasking world, when we split our attention between Facebook and real friends, between our kindles and our kids, between our laptops and our loved ones, we delegate ever more to the unconscious. It makes you wonder who you have looked at today and have not seen. Lessons in Music Has A Good Effect On Aging Brain Something almost like magic happened when Jennifer Bugos played music for her grandparents. “My grandfather with dementia, who could barely utter a complete sentence, sang all of the words to the Battle Hymn of the Republic,” recalls Bugos, now a professor at the University of South Florida. “My grandmother with Alzheimer’s disease, who was in a complete vegetative state, was moving her big toe to the steady beat of the music.”

Their reactions inspired Bugos to investigate how music training could help older adults in the hope of preventing these advanced disease states or potentially mitigating cognitive deficits. Bugos developed a piano intervention for older adults who never played an instrument. For three hours a week, participants learned music theory (reading music), technical exercises (playing scales), and musical pieces from an introductory course book. After six months, participants showed improvement in cognitive skills like attention, multi-tasking, and memory. “Music is a very powerful stimulus that contributes to cognitive and emotional responses,” says Bugos. “Despite physical and cognitive deficits, music has the capacity to break down barriers.” Although hearing, working memory, and other cognitive skills decline with age, studies show people who participate in a little musical practice may be able to gain or maintain these skills. Scientists have learned a lot about the how playing music affects the brain by studying musicians. Compared to older adults with no music training, older musicians can hear better in noisy environments and have better working memory and cognitive control. In a 2018 study, researchers found musicians have “younger-looking brains.” The researchers took MRI scans of professional musicians, amateur musicians, and non- musicians to compare how their brains were aging. “The difference between estimated and chronological age [of the brain] is called BrainAGE [Brain Age Gap Estimation] and now provides information about whether the aging process in the brain is accelerated or slowed down,” says Christian Gaser, one of the study authors and a professor at Jena University Hospital. A low BrainAGE score indicated the brain was aging slowly, while a high score corresponded to accelerated aging. Musicians had lower scores than non-musicians, and less signs of brain aging like the regional brain shrinking typically observed in the brains of older people. Notably, the amateur musicians had even lower scores than professional musicians — their brains were aging slowest. Gaser and his colleagues speculate this may be because amateurs don’t have the stressors from playing music for a living. “Those who only play a musical instrument in their free time may not only have more fun making music, but also the

rejuvenating effect on the brain is more pronounced here as stress factors, as with professional musicians, are eliminated,” he says. Playing music could be associated with cognitive benefits because it’s an exercise session for the brain. “Playing a musical instrument is a whole brain workout,” says Jessica Strong, a clinical geropsychologist and assistant professor of psychology at the University of Prince Edward Island. As you play, you need to coordinate your hands and fingers (and sometimes your feet), while also suppressing excessive movements. In addition to dealing with physical movement, you’re also interpreting and following the sheet music. All the while you’re focusing your attention on the music and ignoring distractions. In the auditory cortex, those changes can last, Strong notes. One study found older adults who had not played an instrument in over 40 years showed faster neural responses to auditory stimuli than individuals who had never played an instrument. The early musical experiences may set up individuals to interact auditorily with the world in a particular way for the rest of their lives.

“Even if an older adult has not played an instrument in a while, there are lasting brain changes in terms of volume or density of particular areas or structures of the brain from having played an instrument earlier in life,” says Strong. In 2018, Strong examined cognitive differences among older active musicians, former musicians, and non-musicians. Participants received tests analyzing their working memory, processing and attention, executive functioning skills, and visuospatial abilities, which help you navigate the environment. Participants with music training scored better in language comprehension, planning, and attention. Strong’s findings from this study lined up with previous research. She notes, “Replicating and extending findings really lends more support for the relationship between playing a musical instrument and late-life cognition.” In 2019, Claude Alain and his team at the Rotman Research Institute examined how music training impacts older adults’ brain activity. The researchers recruited older adults to participate in either a music or visual arts intervention. Participants completed tests measuring verbal comprehension, working memory, and cognitive control. After three months, adults in the music intervention showed greater inhibitory control — they could ignore irrelevant information to stay on track. “Short-term visual arts and music training can boost the brain health of older adults. This is remarkable given the training was only for three months,” says Alain. While scientists have learned a lot about the relationship between music and the aging brain, there’s still more to discover. For example, what’s happening in the brain when people play music and why is it causing positive effects? “We need to get at the mechanisms behind the music training and which pieces of music training contribute to the improvements we are observing,” says Bugos. Still, it’s never too late to start playing.

Parasites Are Going Extinct. Here's Why We Need To Save Them. They’re “gross and slimy and flaccid and wiggling.” But parasites can be just as important as more charismatic animals—and many may be on the verge of disappearing. Growing up, Chelsea Wood dreamed of becoming a marine biologist and studying sharks or dolphins—the kinds of big, exciting animals that biologists call charismatic megafauna. Instead, during a college internship, she found herself peering through a microscope at the guts of a snail. The snail was one she knew well. As a kid, she had often plucked Littorina littorea periwinkles off rocks along the shores of Long Island and dropped them into buckets to watch them crawl around. But she had never seen inside one. She cracked a snail open, teased out the soft parts, and under her magnified gaze saw “thousands of little white sausage-shaped things dumping out of the snail’s body,” she says. The sausages were the larvae of the flatworm Cryptocotyle lingua, a common fish parasite. Seen through the microscope, each one had two dark eyespots, which made them surprisingly cute and charming. “I couldn’t believe that I’d been looking at snails for as long as I had and missing all the cool stuff happening inside them,” says Wood, now a

parasite ecologist at University of Washington. “I just totally fell in love with them. I like to say that they got under my skin.” Wood has since become a leader in a new conservation movement that aims to save the world’s uncharismatic minifauna. Nearly half of all known animals on Earth are parasites, Wood says, and according to one study, a tenth of them may already be doomed to extinction in the next 50 years due to climate change, loss of their hosts, and deliberate attempts at eradication. But right now, it seems few people care—or even notice. Of the more than 37,000 species flagged as critically endangered on the IUCN red list, only one louse and some freshwater mussels are parasites. By definition, parasites live in or on a host and take something from that host. This has made them the pariahs of the animal world. But not all parasites cause noticeable harm to their hosts, and only a small percentage affect humans. Scientists warn of dire consequences if we disregard the rest. Not only is there much can we learn about parasites and ways to use them for our own needs (such as medicinal leeches, still employed in some surgeries), but we’re also starting to understand that they play crucial roles in ecosystems, keeping some populations in check while helping to feed others. Some experts say there’s an aesthetic argument for saving them, too. If you get past the ick factor and get to know them, you may find parasites’ pluckiness eerily charming. They’ve evolved ingenious means of survival, from the crustacean that becomes a fish’s tongue to the jewel wasp that paralyzes part of a cockroach’s brain and then leads it to a nest by its antenna, like a dog on a leash. “People think of parasites as gross and slimy and flaccid and wiggling, and that’s true some of the time,” says Wood. “But if you look at them under the microscope, they are just staggeringly beautiful.” Of course, the modern conservation movement isn’t supposed to care about looks or charisma anyway, says Kevin Lafferty, an ecologist at the University of California, Santa Barbara. There are plenty of nondescript plants and homely, squishy, or creepy-crawly invertebrates that are protected. “None of those things are cute and cuddly,” he says. “The public doesn’t give a damn about them. But modern conservation biology still considers those important parts of biodiversity.”

A world of parasites When we humans look at a landscape, whether African savanna or Australian coral reef, we see the other host species, like ourselves. But the lions and zebras and fish are just homes for most of the life hidden in front of us. All told, 40 percent of known animals are parasites, and those are just the ones that have been described. Scientists think that’s only about 10 percent of all the parasites out there, leaving potentially millions more yet to be discovered. Parasitic wasps alone probably outnumber any other group of animals, even beetles. Most species, it turns out, are parasitized by multiple others. Take humans: Despite our efforts to be unhospitable, we’re excellent hosts. More than a hundred different parasites have evolved to live in or on us, many of them now dependent on us for their species’ continued existence. Parasites proliferate because every living thing is a smorgasbord of nutrients and energy, and being a top predator isn’t the only way to get a bite of that bounty. Parasites opt out of the arms race between predator and prey entirely, choosing an easier path. It’s clever, when you think about it, and it’s exactly why parasitism is so common. “Nature abhors a vacuum. If there’s an opportunity, someone’s going to evolve to fill it,” says Wood. Parasitism has evolved as a way of life again and again, over billions of years, from the smallest and simplest microbes to the most complex vertebrates. There are parasitic plants, parasitic birds, a bewildering array of parasitic worms and insects, and even a parasitic mammal—the vampire bat, which survives by drinking the blood of cows and other

mammals. Of the 42 major branches on the tree of life, called phyla, 31 are mostly parasites. Yet we have barely begun to identify all the parasites, much less learn their lifestyles or monitor their populations. “That’s just not something that we’ve ever really prioritized,” says Skylar Hopkins, an ecologist at North Carolina State University. So a few years ago, Hopkins pulled together a group of scientists interested in parasite conservation, and they started sharing what they knew. In 2018 they presented research at the Ecological Society of America conference. Then, in October 2020, they published the first-ever global plan for saving parasites in a special issue of the journal Biological Conservation. “There should be, potentially, millions of parasite species that are threatened, and probably a lot that have already gone extinct,” One of the things Hopkins and her colleagues have noticed is what they call the paradox of co-extinction. Since parasites by definition need other species, they’re particularly vulnerable to the phenomenon. Take, for example, the endangered pygmy hog-sucking louse. It lives only on another critically endangered species, the pygmy hog, which is disappearing from the grasslands it inhabits in the foothills of the Himalaya. “There should be, potentially, millions of parasite species that are threatened, and probably a lot that have already gone extinct,” Hopkins says. “But the weird thing is that we’ve hardly documented any parasite extinctions.” Wood says she has been hunting for historical data on parasite abundance for more than a decade, for any parasite—on land or in the water. “I’ve had my eyes peeled,” she says, and so far, she has found a grand total of two useful data sets: one from a research cruise in the late 1940s and the other in a lab notebook kept by one of her mentors. With so little information, “we have no idea whether parasites are playing the same role now that they did in the past,” Wood says. “I think that’s a travesty.” The poster child for parasite conservation, if there is one, is the California condor louse, an ironic victim of the conservation movement itself. In the 1970s, desperate to save the California condor, biologists began rearing the birds in captivity. Part of the protocol was to de-louse every bird with pesticides, on the assumption that parasites were bad for condors, though it’s not clear they actually were. The California condor louse hasn’t been seen since. Similarly, the New England medicinal leech hasn’t been seen for over a decade, and overfishing has probably done in the marine fluke Stichocotyle nephropis, which depended

on endangered rays and skates to complete its life cycle. Untold other parasitic worms, protozoans, and insects are presumed to have gone down with the ship, so to speak, as their hosts died out. A world without parasites While the demise of life’s hangers-on might seem like no big deal, or even something to strive for, ecologists caution that wiping them all out would probably spell planetary doom. Without parasites keeping them in check, populations of some animals would explode, just as invasive species do when they’re transplanted away from natural predators. Other species would likely crash in the ensuing melée. Big, charismatic predators would lose out, too. Many parasites have evolved to move into their next host by manipulating the host they’re in, which tends to drive that host into a predator’s mouth. Nematomorph worms, for instance, mature inside crickets but then need to be in water to mate. So, they influence the crickets’ brains, driving the insects to jump into streams, where they become an important food source for trout. Similar phenomena feed birds, fish, cats, and other predators the world over. Even human health wouldn’t entirely benefit from wiping out parasites. In countries such as the United States, where we have eliminated most intestinal parasites, we have autoimmune diseases that are virtually unheard of in places where everyone still has those parasites. According to one line of thinking, the human immune system evolved with a coterie of worms and protozoan parasites, and when we killed them off, our immune systems began attacking ourselves. Some people with Crohn’s disease have even purposely infected themselves with intestinal worms to try to restore their guts’ ecological balance, with mixed results. That said, scientists aren’t eager to save all the parasites. The Guinea worm, for instance, gets a hard pass from even the most hard-core conservationists. It grows to adulthood inside a person’s leg, often reaching several feet long, and emerges painfully through the foot. Former president Jimmy Carter’s foundation has set out to drive the worm to extinction, and few will miss it when it’s gone. If anyone would want to get rid of all parasites, you’d think it would be Bobbi Pritt. As the medical director for the Mayo Clinic’s human parasitology lab, Pritt identifies parasites found all over the country and in every body part. A typical day could see her working with blood carrying malaria parasites, brain tissue full of Toxoplasma gondii, or toenail clippings with sand fleas that someone picked up walking barefoot on the beach. Yet even Pritt has a soft spot for parasites. She writes a blog called “Creepy Dreadful Wonderful Parasites,” and she spends weekends studying the ticks outside her vacation cabin. As a physician, she backs the idea of eradicating parasites in places where they cause disease and suffering. “But as a biologist, the idea of actually going out and purposefully trying to make something extinct just doesn’t sit well with me,” she says.

Ultimately, the goal of promoting parasite conservation isn’t to make everyone fall in love with them. Instead, it’s to call a détente in our war against all of them, because there’s still so much we don’t understand about their value to ecosystems and maybe even to people. And if you’re not swayed by parasites’ usefulness, consider Kevin Lafferty’s take: “If you are a religious person, you’d say they’re all God’s creatures; we should care about them all the same,” he argues. “And that’s kind of the approach that conservation biology has been taking, with one major exception. And that’s parasites.”