Ed Yong: Zombie roaches and other parasite tales | TED Talk | TED.com

Watch this fascinating, hilarious, extremely well written TED Talk.


— excerpt of video transcript below —

Ed Yong

Zombie roaches and other parasite tales

Posted Mar 2014 Rated Fascinating, Informative

A herd of wildebeests, a shoal of fish, a flock of birds. Many animals gather in large groups that are among the most wonderful spectacles in the natural world. But why do these groups form? The common answers include things like seeking safety in numbers or hunting in packs or gathering to mate or breed, and all of these explanations, while often true, make a huge assumption about animal behavior, that the animals are in control of their own actions, that they are in charge of their bodies. And that is often not the case.

This is Artemia, a brine shrimp. You probably know it better as a sea monkey. It’s small, and it typically lives alone, but it can gather in these large red swarms that span for meters, and these form because of a parasite. These shrimp are infected with a tapeworm. A tapeworm is effectively a long, living gut with genitals at one end and a hooked mouth at the other. As a freelance journalist, I sympathize. (Laughter) The tapeworm drains nutrients from Artemia’s body, but it also does other things. It castrates them, it changes their color from transparent to bright red, it makes them live longer, and as biologist Nicolas Rode has found, it makes them swim in groups. Why? Because the tapeworm, like many other parasites, has a complicated life cycle involving many different hosts. The shrimp are just one step on its journey. Its ultimate destination is this, the greater flamingo. Only in a flamingo can the tapeworm reproduce, so to get there, it manipulates its shrimp hosts into forming these conspicuous colored swarms that are easier for a flamingo to spot and to devour, and that is the secret of the Artemia swarm. They aren’t sociable through their own volition, but because they are being controlled. It’s not safety in numbers. It’s actually the exact opposite. The tapeworm hijacks their brains and their bodies, turning them into vehicles for getting itself into a flamingo.

And here is another example of a parasitic manipulation. This is a suicidal cricket. This cricket swallowed the larvae of a Gordian worm, or horsehair worm. The worm grew to adult size within it, but it needs to get into water in order to mate, and it does that by releasing proteins that addle the cricket’s brain, causing it to behave erratically. When the cricket nears a body of water, such as this swimming pool, it jumps in and drowns, and the worm wriggles out of its suicidal corpse. Crickets are really roomy. Who knew?

The tapeworm and the Gordian worm are not alone. They are part of an entire cavalcade of mind-controlling parasites, of fungi, viruses, and worms and insects and more that all specialize in subverting and overriding the wills of their hosts. Now, I first learned about this way of life through David Attenborough’s “Trials of Life” about 20 years ago, and then later through a wonderful book called “Parasite Rex” by my friend Carl Zimmer. And I’ve been writing about these creatures ever since. Few topics in biology enthrall me more. It’s like the parasites have subverted my own brain. Because after all, they are always compelling and they are delightfully macabre. When you write about parasites, your lexicon swells with phrases like “devoured alive” and “bursts out of its body.” (Laughter)

But there’s more to it than that. I’m a writer, and fellow writers in the audience will know that we love stories. Parasites invite us to resist the allure of obvious stories. Their world is one of plot twists and unexpected explanations. Why, for example, does this caterpillar start violently thrashing about when another insect gets close to it and those white cocoons that it seems to be standing guard over? Is it maybe protecting its siblings? No. This caterpillar was attacked by a parasitic wasp which laid eggs inside it. The eggs hatched and the young wasps devoured the caterpillar alive before bursting out of its body. See what I mean? Now, the caterpillar didn’t die. Some of the wasps seemed to stay behind and controlled it into defending their siblings which are metamorphosing into adults within those cocoons. This caterpillar is a head-banging zombie bodyguard defending the offspring of the creature that killed it.


We have a lot to get through. I only have 13 minutes. (Laughter)

Now, some of you are probably just desperately clawing for some solace in the idea that these things are oddities of the natural world, that they are outliers, and that point of view is understandable, because by their nature, parasites are quite small and they spend a lot of their time inside the bodies of other things. They’re easy to overlook, but that doesn’t mean that they aren’t important. A few years back, a man called Kevin Lafferty took a group of scientists into three Californian estuaries and they pretty much weighed and dissected and recorded everything they could find, and what they found were parasites in extreme abundance. Especially common were trematodes, tiny worms that specialize in castrating their hosts like this unfortunate snail. Now, a single trematode is tiny, microscopic, but collectively they weighed as much as all the fish in the estuaries and three to nine times more than all the birds. And remember the Gordian worm that I showed you, the cricket thing? One Japanese scientist called Takuya Sato found that in one stream, these things drive so many crickets and grasshoppers into the water that the drowned insects make up some 60 percent of the diet of local trout. Manipulation is not an oddity. It is a critical and common part of the world around us, and scientists have now found hundreds of examples of such manipulators, and more excitingly, they’re starting to understand exactly how these creatures control their hosts.

And this is one of my favorite examples. This is Ampulex compressa, the emerald cockroach wasp, and it is a truth universally acknowledged that an emerald cockroach wasp in possession of some fertilized eggs must be in want of a cockroach. When she finds one, she stabs it with a stinger that is also a sense organ. This discovery came out three weeks ago. She stabs it with a stinger that is a sense organ equipped with small sensory bumps that allow her to feel the distinctive texture of a roach’s brain. So like a person blindly rooting about in a bag, she finds the brain, and she injects it with venom into two very specific clusters of neurons. Israeli scientists Frederic Libersat and Ram Gal found that the venom is a very specific chemical weapon. It doesn’t kill the roach, nor does it sedate it. The roach could walk away or fly or run if it chose to, but it doesn’t choose to, because the venom nixes its motivation to walk, and only that. The wasp basically un-checks the escape-from-danger box in the roach’s operating system, allowing her to lead her helpless victim back to her lair by its antennae like a person walking a dog. And once there, she lays an egg on it, egg hatches, devoured alive, bursts out of body, yadda yadda yadda, you know the drill. (Laughter) (Applause)

Now I would argue that, once stung, the cockroach isn’t a roach anymore. It’s more of an extension of the wasp, just like the cricket was an extension of the Gordian worm. These hosts won’t get to survive or reproduce. They have as much control over their own fates as my car. Once the parasites get in, the hosts don’t get a say.

Now humans, of course, are no stranger to manipulation. We take drugs to shift the chemistries of our brains and to change our moods, and what are arguments or advertising or big ideas if not an attempt to influence someone else’s mind? But our attempts at doing this are crude and blundering compared to the fine-grained specificity of the parasites. Don Draper only wishes he was as elegant and precise as the emerald cockroach wasp. Now, I think this is part of what makes parasites so sinister and so compelling. We place such a premium on our free will and our independence that the prospect of losing those qualities to forces unseen informs many of our deepest societal fears. Orwellian dystopias and shadowy cabals and mind-controlling supervillains — these are tropes that fill our darkest fiction, but in nature, they happen all the time.

Which leads me to an obvious and disquieting question: Are there dark, sinister parasites that are influencing our behavior without us knowing about it, besides the NSA? If there are any — (Laughter) (Applause) I’ve got a red dot on my forehead now, don’t I? (Laughter)

If there are any, this is a good candidate for them. This is Toxoplasma gondii, or Toxo, for short, because the terrifying creature always deserves a cute nickname. Toxo infects mammals, a wide variety of mammals, but it can only sexually reproduce in a cat. And scientists like Joanne Webster have shown that if Toxo gets into a rat or a mouse, it turns the rodent into a cat-seeking missile. If the infected rat smells the delightful odor of cat piss, it runs towards the source of the smell rather than the more sensible direction of away. The cat eats the rat. Toxo gets to have sex. It’s a classic tale of Eat, Prey, Love. (Laughter) (Applause)

You’re very charitable, generous people. Hi, Elizabeth, I loved your talk.

How does the parasite control its host in this way? We don’t really know. We know that Toxo releases an enzyme that makes dopamine, a substance involved in reward and motivation. We know it targets certain parts of a rodent’s brain, including those involved in sexual arousal. But how those puzzle pieces fit together is not immediately clear. What is clear is that this thing is a single cell. This has no nervous system. It has no consciousness. It doesn’t even have a body. But it’s manipulating a mammal? We are mammals. We are more intelligent than a mere rat, to be sure, but our brains have the same basic structure, the same types of cells, the same chemicals running through them, and the same parasites. Estimates vary a lot, but some figures suggest that one in three people around the world have Toxo in their brains. Now typically, this doesn’t lead to any overt illness. The parasite holds up in a dormant state for a long period of time. But there’s some evidence that those people who are carriers score slightly differently on personality questionnaires than other people, that they have a slightly higher risk of car accidents, and there’s some evidence that people with schizophrenia are more likely to be infected. Now, I think this evidence is still inconclusive, and even among Toxo researchers, opinion is divided as to whether the parasite is truly influencing our behavior. But given the widespread nature of such manipulations, it would be completely implausible for humans to be the only species that weren’t similarly affected.

And I think that this capacity to constantly subvert our way of thinking about the world makes parasites amazing. They’re constantly inviting us to look at the natural world sideways, and to ask if the behaviors we’re seeing, whether they’re simple and obvious or baffling and puzzling, are not the results of individuals acting through their own accord but because they are being bent to the control of something else. And while that idea may be disquieting, and while parasites’ habits may be very grisly, I think that ability to surprise us makes them as wonderful and as charismatic as any panda or butterfly or dolphin.

At the end of “On the Origin of Species,” Charles Darwin writes about the grandeur of life, and of endless forms most beautiful and most wonderful, and I like to think he could easily have been talking about a tapeworm that makes shrimp sociable or a wasp that takes cockroaches for walks.

But perhaps, that’s just a parasite talking.

Thank you.


© TED Conferences, LLC

For healthier buildings, just add bacteria? |


— excerpt below —

Search Icon

Search for:


    Arts + Design


    We humans

For healthier buildings, just add bacteria?

Jan 24, 2017 / Ed Yong


Sacha Vega/TED

Just like a human being, a house or office has its own microbiome, with good and bad microorganisms. One researcher has a targeted idea: to customize our spaces with the right microbes.
Right before the University of Chicago’s Center for Care and Discovery opened in 2013, a team of researchers — overseen by Jack Gilbert, microbial researcher and director of the Microbiome Center at the University of Chicago — went through the eerily empty hallways, armed with bags of Q-tips. None of the rooms were home to humans yet; their only residents were microbes, which the team was there to collect. They swabbed the pristine floors, the gleaming bedrails, the perfectly folded sheets. They collected samples from light switches, door handles, air vents and more. Finally, they fitted the rooms with data loggers to measure light, temperature, humidity and air pressure, carbon dioxide monitors that would automatically record if a room was occupied, and infrared sensors that could tell when people entered or left. After the hospital opened, the team collected weekly samples.
Just as others have catalogued the developing microbiome of a newborn baby, Gilbert has, for the first time, catalogued the developing microbiome of a newborn building. His team is analyzing the data to work out how the presence of humans has changed the building’s microbial character and whether those environmental microbes have flowed back into the occupants. Nowhere are those questions more important than in a hospital. There, the flow of microbes can mean life or death — a lot of deaths. In the developed world, around five to ten percent of people who check into hospitals and other health-care institutions pick up an infection during their stay, falling ill in the very places that are meant to make them healthier. In the United States alone, this means around 1.7 million infections and 90,000 deaths a year.
Ever since the 1860s, when Joseph Lister instigated sterile techniques in his hospital, cleaning regimes have helped curb the spread of pathogens. But just as we have gone overboard in taking unnecessary antibiotics or lathering ourselves in antibacterial sanitizers, we have also gone too far in cleaning our buildings, even our hospitals. As an example, one US hospital recently spent around $700,000 to install flooring that was impregnated with antibacterial substances, despite no evidence that such measures work. They might even make things worse. Perhaps the quest to sterilize our hospitals has created dysbiosis in the microbiomes of our buildings. By removing harmless bacteria that would otherwise impede the growth of pathogens, perhaps we have inadvertently constructed a more dangerous ecosystem.
    Researcher Gilbert has visions of adding microbial spheres to neonatal intensive care units, to expose babies to a ‘rich microbial ecosystem’
Rather than trying to exclude microbes from our buildings and public spaces, perhaps it is time to lay the welcome mat out for them. One of Gilbert’s many microbial ideas: to deliberately seed buildings with bacteria. The microbes won’t be sprayed or plastered onto walls. Instead, they’ll come caged within tiny plastic spheres, created by engineer Ramille Shah. She will use three-dimensional printers to fashion balls that contain a warren of microscopic nooks and crannies. Gilbert will then impregnate these with useful bacteria like Clostridia, which digests fiber and quenches inflammation, as well as nutrients that nourish those microbes.
These bacteria should then jump over to anyone who interacts with the spheres. Gilbert is testing this with germ-free mice. He wants to see if the bacteria are stable in their cages, if they jump into rodents that play with the balls, if they last in their new hosts and if they can cure the rodents of inflammatory diseases. If that works, Gilbert has visions of testing the microbial spheres in office blocks or hospital wards. He imagines adding them to the cots in neonatal intensive care units, so that the infants would “be constantly exposed to a rich microbial ecosystem that we’ve designed to be beneficial.” He adds, “I want to create 3D-printable teething toys, too. You can imagine children playing with these.”
These spheres are effectively a different take on probiotics — a way of delivering beneficial microbes not through yogurt drinks or nutritional supplements, but via an animal’s surroundings. “I don’t want to put the microbes in their food and shove it down their gullet,” he says. “I want the microbes to interact with their nasal membranes, their mouths and their hands. I want them to experience that microbiome in a more natural way.”
    Microbes that prevent dandruff and dermatitis might be used to stop mold from developing in homes
But Gilbert is interested in implementing his ideas on a much larger scale. He wants to shape the microbiomes of entire cities, starting with Chicago. He has been talking to architect Luke Leung, who designed the world’s tallest building, Dubai’s Burj Khalifa. Since meeting Gilbert, Leung has also become something of a microbiome fanatic. In several of his buildings, Leung has routed the ventilation system so that it flows through a wall of plants, which not only pleases the eye but also filters the air. To him, Gilbert’s idea of lacing walls with microbial spheres — which I’ve suggested should be called Baccy Balls — makes perfect sense. Karen Weigert, Chicago’s chief sustainability officer, has also become a microbiome enthusiast.
The four of us — Leung, Gilbert, Weigert and me — are meeting for lunch at a Chicago restaurant overlooking Lake Michigan. Like Leung, Weigert is excited about using bacteria in architecture, and she asks Gilbert if the Baccy Balls would work in low-income housing, as well as in skyscrapers. Yes, he says. He wants to make them as cheaply as possible.
She switches the conversation to Chicago’s perennial problem with flooding. The sewer system backs up a lot and will probably do so more and more as the global climate changes. “Is there something we can do to manage flooding, or after-effects like mold?” she asks. “There actually is,” says Gilbert.
In a different project, he has been working with L’Oréal to identify bacteria that can prevent dandruff and dermatitis, by stopping fungi from germinating on the scalp. These microbes could form the basis of anti-dandruff probiotic shampoos, but they could also be used to create “micro-wetlands” that stop flooded homes from becoming overrun by mold. So if a home floods, fungi would get a bonanza of water, but also face a bloom of antifungal microbes. “You’d get automatic built-in mold control,” says Gilbert.
“So how real is all of this? Where are you with it?” asks Weigert.
“We’ve got the fungal control agents, and we’re trying to work out how to implant them into plastics,” says Gilbert. “We’re probably two or three years off from having something that we’d feel comfortable inserting in somebody’s home — someone who wasn’t a colleague. And it may be three or four years before we have something reliable we can roll out.”
“We’ve been getting pretty good at killing bacteria, but we want to revitalize that relationship,” Leung says. “We want to understand how the bacteria can help us in the built environment.”
    It’s the start of a new era, when people are finally able to embrace the microbial world.
Manipulating the microbiomes of buildings and cities is just the start of Gilbert’s ambitions. As well as the hospital and aquarium initiatives, he is also studying the microbiomes of a local gym and a college dorm. He and microbial researcher Rob Knight at UC San Diego (TED Talk: How our microbes make us who we are) are looking into forensic applications. He is studying the microbiomes of a wastewater treatment plant, floodplains, oil-contaminated waters in the Gulf of Mexico, prairies, a neonatal intensive care unit and Merlot grapes. He is studying how gut microbes change over the course of the day and whether that affects our risk of becoming fat. He is analyzing samples from several dozen wild baboons to see if the females that are most successful at rearing young have anything distinctive in their microbiomes.
Finally, together with Knight and Janet Jansson (of the Pacific Northwest National Laboratory), Gilbert is coordinating the Earth Microbiome Project — a breathtakingly ambitious plan to take full stock of the planet’s microbes. The team are making contact with people who work on oceans or grasslands or floodplains, and persuading them to share their samples and their data. Ultimately, they want to be able to predict the kinds of microbes that live in a given ecosystem by plugging in basic factors like temperature, vegetation, wind speed or levels of sunlight. And they want to predict how those species would respond to environmental changes, like the flooding of a river, or the passage from night to day. As goals go, it is ludicrously ambitious; some would say, unachievably so. But Gilbert and his colleagues are undeterred.
Now is a time for thinking big. It’s a time when families can be persuaded to swab their houses for researchers, when aquarium managers are as concerned about the invisible life in their waters as they are about the charismatic dolphins, when hospitals are seriously considering adding microbes to walls rather than removing them. It’s the start of a new era, when people are finally ready to embrace the microbial world.
Excerpted from the new book I Contain Multitudes: The Microbes Within Us and a Grander View on Life by Ed Yong. Copyright 2016 Ed Yong. Reprinted with permission from Ecco, an imprint of HarperCollins Publishers.

About the author
Ed Yong writes the award-winning blog Not Exactly Rocket Science (hosted by National Geographic). He also contributes to Nature, Wired, Scientific American and many other web and print outlets.
    baccy ballsbacteriabook excerptearth microbiome projectEd Yongjack gilbertJoseph ListerKaren WeigertLuke LeungmicrobesmicrobiologymicrobiomeRamille ShahRob Knight

© TED Conferences, LLC Powered by WordPress.com VIP


The Tiny Robots Will See You Now – IEEE Spectrum


— excerpt below —

IEEE Spectrum | The Human OS, Biomedical,  Biomedical Devices

The Tiny Robots Will See You Now

By Megan Scudellari

Posted 1 Mar 2017 | 19:00 GMT
Over the past week, we’ve highlighted a lot of big, impressive robots. Now it’s time to pay homage to their teeny, tiny counterparts.
It’s science-fiction-turned-reality: Researchers are developing micro- and nanoscale robots that move freely in the body, communicate with each other, perform jobs, and degrade when their mission is complete. These tiny robots will someday “have a major impact” on disease diagnosis, treatment, and prevention, according to a new review in Science Robotics from a top nanoengineering team at the University of California, San Diego.
The review highlights four areas of medicine where tiny robots have been successfully used in proof-of-concept studies: targeted delivery, precision surgery, sensing of biological targets, and detoxification. Of those, “active drug delivery is primarily the most promising commercial application of medical microrobots,” said paper co-author Joseph Wang, chair of nanoengineering at UCSD, in an email to IEEE Spectrum. In December, for example, researchers at ETH Zurich in Switzerland showed that a wire-shaped nanorobot could be wirelessly steered toward a location and then triggered by a magnetic field to release drugs to kill cancer cells.
To get to know these little machines better before we meet them in the doctor’s office, here are five things to know about micro- and nanorobots:
1. They are hard to move—and even harder to power.
Two of the key challenges of miniaturizing robots to the micro- and nanoscales are locomotion and power. You simply can’t fit gears or a battery on these guys. Many of the robots employ a swimming strategy and are either chemically powered or externally powered by magnetic fields or other energies, including light, heat, or electricity. One of Wang’s favorites is a “nanorocket” his team developed that propels itself in the stomach or gastrointestinal tract using gastric fluid as fuel and leaving a trail of bubbles in its wake. Still, the field continues to look for new energy sources that last longer that current sources and will work autonomously, without a technician’s intervention.
2. They can perform surgery.
Robot-assisted surgery is now common, translating doctors’ hand movements to smaller, precise motions inside a patient’s body. Now, imagine that on the nanoscale. Scientists are developing nanodrillers, microgrippers, and other tools to be injected into the body, travel to particular areas in the body, and then capture or remove certain tissues, such as a clump of cells for biopsy. In one recent example, researchers constructed a tube-like microrobot that performed surgery, injecting a needle into the back of a living rabbit’s eye. The motion of the robot was controlled with magnetic fields.
3. They’ll cooperate via swarm intelligence.
Micro- and nanorobots aren’t expected to work alone; hundreds to thousands of units will cooperate to do a job. “These microrobots can swarm into small schools to perform a collective action,” says Wang. For that to happen, scientists will need to instill de-centralized communication called swarm intelligence. That can be done using group motion planning and machine learning, according to the paper.
4. They’re designed to destroy themselves after completing a mission.
Let’s be honest—no one wants a bunch of nanobots sticking around inside of their body once the job is done, whether it be surgery, drug delivery, or something else. So scientists are constructing the robots out of biodegradable materials that stay in a patient’s body for a limited amount of time, and then are cleared or disappear once the job is completed.
5. They’re being used in live animals.
Wang’s nanorocket, mentioned earlier, was the first artificial micromotor to be tested in a live mouse model. Today, more labs are testing their tech in live animals, says Wang, including at ETH Zurich and the University of Montreal. If successful, this in vivo work should lead to clinical trials in humans, says Wang. Who wants to sign up first?

    © Copyright 2017 IEEE Spectrum

The Space Without



Using Computer Vision and AI to interpret the world for the visually impaired.

Same technology that brings us facial recognition, and self driving cars.




Visualized by Jeff Nishinaka

Source: The Space Without