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The Kingdom: How Fungi Made Our World (2018)
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(bird screeches) (ominous music) (woodpecker pecking) Hidden from site is a kingdom that rules all life on land. They're landing on me. We have this coding that's falling right now all around us. They're on your food, they're in your lungs, they're on your skin, they're on each thing you touch. They're each place you go. They are a single interconnected network. Could be described as a third mode of life. It's an alien world of powerful ancient life forms. This entire web of life is connected, and it's connected through the fungi. Some of those will save us, some of those threaten us, and we're just beginning to understand which are which. They shaped our world, and hold the key for our future. This is the kingdom of fungi. (inspirational music) (bright music) (birds chirping) Fungi are not plants, they're not animals. They're a kingdom in their own right. Many people think of them as plants, perhaps because they don't move, they just sit there. But in fact, fungi are much more closely related to animals than they are to plants, and like animals, they have to eat other organisms. When we think of fungi at all, we think of mushrooms. But these are just the fruit. A small part of the fungal life that's all around us. They're just the tip of the iceberg. They're the outward sign of a presence of a fungus. Ah, look at this. The main part of fungus is a whole mass of fine filaments, which together form what is called the mycelium. The mycelium is the body of the fungus. It spreads through the soil eating everything in its path, and even penetrates solid wood. They can get there by physical penetrative force, but also by producing enzymes which digest the materials that they're growing into. These enzymes are the teeth and claws of fungi. Well we're very familiar with single celled organisms, could be bacteria. And and multicellular organisms, so plants and animals. The fungi are unusual because they are a single interconnected network. So much is unknown. Almost every time we do an experiment, we're seeing something that nobody else has ever seen before. The whole of their growth and development depends on what's going on in their environment, whereas for animals and plants, for an animal, once you've got your arms and your legs, you don't grow a new one depending on whether you need it or not. Unlike animals, the body of the fungus is constantly changing shape in a relentless search for food. It can keep spreading. And it can recycle material that's not useful, and use all of that material to grow somewhere else. So it can actually migrate in the environment depending on whether it can find food or not. During a billion years of evolution, fungi became the masters of survival. The fungi have been around so long, it means they've had a long time to figure out the best ways to do everything. The best ways to be lethal, the best way to kill the things they fight. You know, they have a billion years of experience in doing the hard work of living. We have much to learn from this mysterious kingdom. Yet we know less than 1% of the estimated five million fungi species. We're still incredibly ignorant about these organisms. Every time you breathe in, you're breathing in hundreds of species of fungi. And even those fungi we've studied for hundreds of years, they're really basic things we don't necessarily know about them. Microbial explorers Rob Dunn and Anne Madden are out to discover how fungi can change our lives. We don't have to go to far off lands or distant places because there's new species underneath our feet. With each new species is the promise of a new compound that could be the next greatest antibiotic, or a chemical that could cure cancer, or something that we don't even know what it could do yet. Ah, we've become really interested recently in trying to figure out how do we find not just any new fungus, but fungi that might be useful to people. And so in some cases that fungi we might use for making new kinds of beer. In other cases though, we're looking fungi that might be able to break down industrial waste, human waste, we'll need fungi to help us deal with that. Most of the coolest stuff nature can do we haven't discovered yet. And so we both systematically look, and we bumble around a little bit. It's cool, bark's like a magical thing you lift and any kind of drama can be playing out underneath it. It's a microscopic mystery inside a microscopic mystery. We need some way to guide us toward understanding all of this mystery. And so I think evolutionary history serves as the compass to guide us. It points us in a direction. This is the great untold story of how fungi shaped all life on land. And to understand it, we need to go way back in evolutionary time. (ominous boom) (bright chime) A billion years ago, planet earth is waking from a prolonged ice age. Retreating glaciers reveal a barren landscape. And yet from this bleakness will emerge all the abundance of terrestrial life. In the lava fields of Iceland, we find evidence of the first colonizers. I'm really excited to see what's living here that we're not seeing. On these rocks there are signs that microscopic fungi were amongst the pioneers. About a billion years ago, terrestrial earth started to be colonized by microbes. And those microbes included bacteria, and eventually also fungi in crust like communities. The first terrestrial fungi survived by mining minerals from rocks. They are literally carving out an existence. When we look at a volcanic landscape like this one, it's hard to imagine that fungi have anything to do with the story. Fungi are fragile, they're mushrooms, and teeny little microscopic spores. And yet fungi are precisely at the center of this story because fungi are what turn a rock like this into soil. Fungi eat rock. They produce spores that release acid, breaking up the rock's surface. Fast growing fungal filaments, hyphae, then drill into the rock to extract a meal of minerals. Using pressure a hundred times greater than inside a car tire, the tips of the hyphae can crush the rock. What we're looking at here is a kind of molecular mining operation. It's this sort of process through which fungi turn rock to life. By mineralizing rocks, fungi will slowly lay the ground work for the coming of the first plants. But that next step of colonizing earth was a big one. Around 500 million years ago, a group of algae started to move from the ocean to freshwater ponds on land. But to take a foothold on ground, they'd need to make a deal with fungi. Organisms living in water are bathed in a solution of nutrients. When they move to land it's a very different scenario. So it's very difficult then, to be able to get ahold of the water and the nutrients that they need to grow. One of the major strategies very early on would've been to link up with this fungi that were established on land. Fungi at the time are living on bacteria and decaying seaweed washed up on the shore. The arrival of land plants offers fungi an easier way to access food. By exploiting a living organism to get sugar out of them rather than having to excrete their own digestive enzymes and then assimilate all the nutrients, that's energetically a lot less expensive for the fungus. So it makes economical sense. When algae emerge from lakes, they're ready for a trade. They offer the fungi sugars, and in return receive essential minerals. This mutually beneficial relationship is a form of symbiosis. And it will become one of the most powerful forces of evolution. And so when that first algal cell hits the terrestrial ground, it was already ready to say I'm here, let's form a relationship. Microbiologist, Dr. Erik Hom, has reignited the romance between fungi and algae. I'm always fascinated, even in human relationships, who's gonna hit it off and why? Dr. Hom's experiment shows that even 500 million years later, fungi and algae will work together again. So if I were to ask you how long do you think these guys could maybe form a symbiosis together, what would you say? It doesn't seem like a forgone conclusion that they would form a partnership. Yes, so they can form a partnership, and this is a result of just seven days. So not-- Wait, that's (mumbles). So you put these together right, that are both just hatin' life, and in seven days you get this? Yes, they find each other. And so the fact that these are together means that the algae are actually embedded somehow in the ivy? Yes, they're actually psychically attached. Like arm and arm. That's awesome. To me this is pretty fantastic, and I love the idea that you're remaking this dance that must've happened, and yeah, there's a beauty in that. This symbiosis between fungi and algae will open the way to the evolution of all land plants. It's the biological big bang. That first jump was a big one in the greening of a dark, dark land. 450 million years ago, the earth is teeming with bizarre lifeforms. But nearly all of it is still in the ocean. The land is void of animals, trees, and flowering plants. Only mosses cushion the lava fields, and simple plants cling to the edges of streams. They had no leaves, they had no roots, and so they were limited to just staying around the water because they had no way of storing it or transporting it. Like their algae ancestors, these early plants will reach out fungi for help. Those fungi would've been already well established in the earth at that time, and they would've been able to go a lot deeper and get into smaller crevices in the soil and be able to sort of mine that soil. Martin Bidartondo studies the interaction between fungi and the oldest land plants, liverworts. Imagine that the fungi were making contact with this plant surfaces, this shallow growing plants. And they would be growing around them rather than into them. As fungi explore the liverworts, they find their way in between plant cells. Some even manage to break inside. So the fungi were able to occupy the plants themselves and form these beautiful tree like structures which we call arbusculars, and it's through these arbusculars that the plants are able to take phosphorous from the fungus, and in return the plant gives the fungus carbon that its generated through photosynthesis. Katie Field can recreate the atmosphere of 450 million years ago when fungi and liverworts began cooperating. So what we've done is we've ramped the CO2 right up to around three times its level in the current atmosphere. So I'll just have a quick look and see how the liverworts are doing in there. So this is one of my favorite liverworts, this is trabial lacunosa, and it's actually the most ancient land plant on earth today, and it's probably really similar to how the very first land plants were back 400 million years ago. And as you can see, it's doing really well under those high CO2 concentrations in this cabinet, which suggest that the fungi is doing it's job and it's supplying it with nutrients from the soil, and the plant's doing really well because of that. By working with fungi, liverworts not only survive, they thrive. Sucking up carbon dioxide and pumping out oxygen, these tiny plants are giving the planet its first breathe of fresh air, and over time, they change the composition of the entire atmosphere, paving the way for the emergence of complex plants. And so you end up with these much larger plants evolving which have leaves, stomata, which are able to control the CO2 movement into the leaves. And roots, which allow the plants to grow really big up above ground. And ever since, nearly every plant has been nurtured by their symbiotic fungi. I am still captivated by this whole idea of a plant that is alive, that is healthy, and that it's allowing another organism to grow in between its cells and into its cells, and that not only is it allowing them to do that, but it's actually deriving a benefit from it. Well ultimately, fungi help plants move away from being these marginal, tiny little things on the water's edge into large forests and entire ecosystems. If fungi had not evolved, it would be a very, very radically different looking kind of planet. We certainly wouldn't be here. Long before the first forests arrive, it's fungi that rule the world. For 50 million years, giant organisms called prototaxites, tower up to eight meters above the landscape. So strange and inexplicable. Scientists have argued about them for a century. Prototaxites is identified as a fossil wood. And I thought, I looked at the tissue myself, I said that can't possibly be. So got intrigued, well let's find out what it is. And there was nothing that you could compare to any modern wood. And so well, the other next thing, well, maybe it is a fungus, and I'll check that out with present day woody fungi, bracket fungi. They are very woody and they're very hard. Material that's been weathered in the dessert. Dr. Francis Hueber has spent a lifetime trying to make sense of these enigmatic fossils. Well you see this kind of structure, it's definitely not wood. These are hyphae, these are tubes. And this is typical in what you see in the fungus today when you make a section of a bracket fungus. You see very much a similar arrangement of various size tube elements. These massive mushrooms spread to every continent. They had no rivals until insects appeared and begun eating them from the ground up. I just sort of jokingly say, well prototaxites got tired of being fed upon on the ground, and it climbed a tree, and became a bracket fungus. These strange fossils are all that's left. A reminder of evolution's bizarre experiments. (dinosaurs roaring) In the golden age of the dinosaurs, the planet is exploding with life. Tree ferns and conifers dot the landscape, but it's fungi beneath the ground that's making this all possible. Fungi are the kind of classic out of sight out of mind type of organisms, but if you take a step back, the fungi are really the organisms that are putting those plants there. With the coming of trees, new type of fungi evolve. They'll forge partnerships with the roots of trees, and give rise to entire forests. (mumbles) is a fungi that are able to do something quite different in the soil than what the early fungi that were involved in allowing plants to colonize land could do. Above ground, these new fungi are marked by their fruiting bodies, mushrooms. Beneath the surface they form complex networks. Scientists call it the wood wide web. In fact, there are two sorts of wood wide web. One sort is formed by the decompose of fungi, the rotters that break down dead plant material, and they interconnect between lots of different dead resources. Without these decomposers, life in the forest would soon be buried under dead stuff. Fungi eat death, and in doing so, they create life. They're the garbage disposal agents of the natural world. They break down dead, organic matter, and by doing that they release nutrients, and those nutrients then made available for plants to carry on growing. Otherwise all the nutrients on the planet would be locked up in dead stuff. Fungi are taking all of that dead stuff and giving it back to life. It's how everything is reborn, so that this entire web of life is connected, and it's connected through the fungi. The second type of wood wide web is formed between living plants, especially trees. Hungry for food, fungal filaments called hyphae are searching for tree roots. They envelope the root, and some find their way inside. Here, they'll provide water and minerals in exchange for sugars. But this is more than a trade. The entire forest is now connected through the fungi. If you summed up the distance traveled by the hyphae just beneath a single foot, it would be more than 500 kilometers of hyphae. A vast network that traffics in everything that forests need. This is nature's internet. An information highway that allows trees to communicate and even send out danger signals to each other. It's as if the forest isn't made of individual trees, but is operating as a super organism. Connected by the fungal network, a lush and vibrant planet emerges. But hundreds of millions of years of evolution is about to be swept away in a single moment. (explosion) This asteroid strike will wipe out 70% of all species. Yet fungi, nature's ultimate survivor, will turn the cataclysm to it's advantage. The earth became a fungal compost. Think about it. Overnight you have this catastrophe. Dust is kicked up, there is no sunlight. And you have all this decaying plant matter. The fungi then can reproduce very rapidly. In this expansive death, fungi inherit the earth. And incredibly, without this catastrophe, we wouldn't be here. An otherwise insignificant animal group, the mammals from whom we will evolve, survive. They are immune to fungi's lethal embrace. Mammals have one built in advantage relative to the reptiles. They're hot. The reptiles are quite susceptible to fungal diseases, but your typical mammal, which maintains a temperature in the mid 30s or so, creates a thermal exclusionary zone for fungi. It's an intriguing theory, and if correct, the temperatures of warm blooded animals would be above the temperature tolerated by most fungi. Casadevall's team set out to test the hypothesis. So after two days in culture at either 25 degrees, which is ambient room temperature, or 37, degrees which is human body temperature, we can see that there are differences in growth. So on the 25 degree plate, we can see all four of these strains grew. But on our 37 degree plate, we can see two of those fungi haven't grown at all. And that's because they don't survive at 37, and it happens to be that those are the same ones that cannot infect people. The narrow margin protecting us from fungal pathogens is the difference between life and death. In America, millions of little bats are dying from a newly arrived fungus. Bats are like us, warm blooded. However, the bats hibernate in the winter, and when their temperature drops, they become selectable to this fungal disease. Here is the interesting thing. If you take the bats when they're infected, and you feed them, wake them up, and let their temperatures go up, they're able to control the fungal disease. But when they're cold, their immune system cannot do it by itself. The warm bloodedness of mammals, including ourselves, has evolved in part as a response to the pressure from fungus. And so we seem to have cooked out the fungal pathogens. Protected by their high temperature, mammals were free to roam the fungi dominated world. 10 million years ago, the climate became warm and dry. Forests gave way to grasslands, and our ancestors began to explore life on the ground. Their fate would be altered by the simplest of fungi, yeast. In the trees you find lots of fruit that is unfermented. But when it gets old and falls to the ground, it can get damaged, yeast can get into the fruit, and then they can start fighting a war with the bacteria, and how do they fight that? They make ethanol. So if you're adapting to life on the ground, you're more likely to encounter fermented fruit than you are unfermented fruit. But eating alcohol laden fruit when you are surrounded by predators, isn't a great idea. If you do eat that fermented fruit, and you cannot metabolism the ethanol, you get inebriated, you get intoxicated, and is this a good survival strategy when you're wandering around the forests surrounded by predators or competing with other animals? Probably not. Biologist Matthew Carrigan discovered that our early ancestors were able to break down alcohol. What we know from some of the enzyme's that we've studied is that our ancestors with these guys and with gorillas, we got a mutation that allowed us to metabolize ethanol really well. And in a world where food is scarce, that can be difference between life and death. If there's no other things to eat, then having ethanol in fruit is better than starving. And those ancestors that could tolerate alcohol had a better chance to survive, and eventually to evolve into us. What we've evolved is to consume ethanol and not get intoxicated, not get legally drunk. Cheers! Yeah, yeast, gotta love 'em. A single mutation in our deep evolutionary past paved the way to one of our favorite pastimes. And since that moment, our history has been intertwined with yeast. If you think about the transition in human history from being a hunter gatherer to being an agricultural society to being an empire, and so key to that transition would be fungi. Farming sowed the seeds for modern society. Civilization began because of agriculture. We thought these grains were grown to bake bread, but what if they were harvested to brew beer? There's actually evidence suggesting that yes, the very grains that were chosen in those early days included grains that were really the very best not for bread but instead for beer. Both baking and brewing rely on yeast for fermentation, but brewing beer has the added advantage of sterilizing against bacteria. In those early gatherings of humans, we pooped on everything. The danger of getting infected and sick was very high, and it was especially higher from the liquids that you would drink. And so in that context, fermented drinks might've actually increased our ability to survive ourselves. We've built our civilization around a single, microscopic fungus. For 10 thousand years, every glass of beer and every loaf of bread has been made with the very same yeast. Anne Madden and Rob Dunn set out to change that. There are many more yeast species that exist in our world. And so our idea was, maybe we could go to these wild yeasts and see if they produced different, new, and valuable beers. In one of the places we decided to first search were the bodies of social wasps. As wasps pollinate flowers, they incidentally pick up yeast that are feasting on the nectar. So we knew that wasps are a reservoir of yeast in the environment, and we went to explore and wrangle yeast from these wasps. We grabbed a species of yeast that hasn't ever been worked with for brewing. So here we have four different yeasts that came from the different arthropods we were looking at. And you can see that the yeasts look quite different. They've got different pigments produced. And they all have a different smell. So you get kind of a fruity note in that one. Whoa. Yeah, and that's likely gonna come through in the beer, so we wanna keep that in mind when you look through them. Now most yeasts can't produce alcohol, and if they can produce alcohol, they produce horrible flavors. (laughs) So not that one? That wasn't fair, that was a trick! So we had very low chances of success, but we found a few yeasts with this remarkable ability to produce alcohol. So I sent them off to our brewer and didn't really expect to hear much back. This was a long shot of a chance in science. But then a few weeks later I get an email, and it's John. And he says, the yeast made beer. That's right, the yeast that was originated from the wasp body is now making our beer for us, and you're about to drink it. I don't know how I feel about that. Should I feel good? Well, try it. All right, here we go. Well that's quite good. You like that? v -Yeah! Wasp being delicious and a little bit fungal too, I like it. Fungi have given us more than beer and bread. Our ancestors long recognized them as life savers. 5,000 years ago this beautiful area here in the Italian Alps was already settled by people. And this man was going on his journey, packed with a lot of equipment, but he would never return home, unfortunately. This is tzi, the Iceman. A victim of a neolithic murder. His body was perfectly preserved in the ice for thousands of years, and amongst his belongings were some intriguing items. There were two objects which were a big mystery in the beginning. They've turned later out to be fungi, polypores. We were thinking, could it be food? But he would not put a lot of work in food to make it so nicely ramented. Dr. Ursula Peintner is one of the scientists who studied these mushrooms. The evidence suggests they were much more than decoration. Now we know that it's enhancing your immune system and it will help you also against cancer, against inflammations, antiviral, it's antibacterial, so it has a huge array of medicinal properties. tzi's bracket fungi are the first recorded use of mushrooms as medicine, but for the Iceman it meant even more. It was a talisman, it was spiritual. Like bringing the spirit of God with you to protect you on your journey. (church bells ringing) In western culture, the power of mushrooms will soon be forgotten. And it's only an accident that revives it. In 1928, fungal spores blow through the window of a London hospital. They land in a Petri dish in the laboratory of Alexander Fleming. This fungus, called penicillium, will change human history. He looked at one of these unusual Petri dishes, and at that interface between the bacteria and the fungi was a zone where nothing was growing. What he would come to realize was that was the zone where the fungi were producing enzymes, chemicals, that were outside of the body of the fungus and killing the bacteria. And that's the germ of the discovery of antibiotics. For most of history, humanity was decimated by bacterial epidemics. But since the first penicillin pill, world population has tripled and allowed us to build vast cities changing the face of the planet. We're expected to add another two billion people to the planet, we'll need more food. With that number of people we'll need more antibiotics. And so we're going to need to depend on fungi more than we do today. The life saving power of antibiotics is the outcome of an ancient war. Fungi and bacteria are sworn enemies. Wherever fungi grow and they encounter bacteria, and over millions and millions of years, they've evolved mechanisms to kill those bacteria. Fungi are absolutely remarkable chemists. They make molecules that are almost impossible, frankly are impossible, for us to replicate in the lab right now. But bacteria are constantly evolving. And as a result, we are now facing a global crisis of antibiotic resistance. Unless we find a solution, hundreds of millions will die. The challenge is we don't have any new drugs. And what we need to do is find new ways to overcome this problem. Microbiologist Gerry Wright wondered if fungi had evolved ways of beating bacterial resistance. And that meant returning to the soil looking for a compound that might help to safeguard our antibiotics. Hey guys, got some more dirt for you. It came from the back of the university. Thank you. See if you can't get anything cool out of it. Okay, sounds good. We screened 10,000 extracts that we had collected from microorganisms around various environments, and from that 10,000 extracts, we found one that had excellent activity at overcoming resistance. We call it AMA for short, cause aspergillomycosis is too much to say every day. Incredibly, this compound produced by a common soil fungus, aspergillus, restored the power of our antibiotics. When I saw the result, I honestly didn't believe it. It just seemed relatively too easy to do. But it turned out to be real, so every week, every month, as we continue to work on this compound and kept saying, well, can it be used for pneumonia, or can it be used for this kind of an infection, every time we did an experiment like this it was proving to be really effective. When these fungal molecules were added to antibiotics, even the most resistant superbugs were defeated. I've been working in this field for 25 years, we've never had any molecule that's shown to be that potent and that's insanely exciting. The kingdom of fungi is nature's chemical factory offering immense benefits to humanity. Already, half of our 20 most valuable medicines are derived from fungi, including immunosuppressants and cholesterol lowering statins. Many of the new drugs we're thinking about are coming from fungi, and so in your every day life, they're this magic set of compounds that we rely on. Scientists are now investigating the benefits of a wide range of mushrooms for their antiinflammatory, anticancer, antioxidant, and immune stimulant properties. A challenging thing as a scientist is trying to understand why they're doing it and we do tap into that and actually enhance our chances of finding what we want. With millions of potential candidates, the search for beneficial fungi needs clever detective work. The great thing is they're a bunch of insects that we know probably have useful fungi, but then there are lots of other insects that nobody's ever studied in the context of fungi. And so what we've started to do is to look to social insects, who like us, have many challenges with microbial pathogens that would like nothing other than to destroy their entire society. Holy moly. One promising candidate is nature's worst housekeeper, the winnow ant. Seemingly oblivious to hygiene, the ants live surrounded by waste and decaying bodies. Right next to the larvae and the eggs we found a whole bunch of ant poop and ant skeletons, dead ants, and so almost certainly that means the ants are doing something interesting. Think about it in the context of your own life. If you had in your bedroom a bunch of poop and dead bodies, you'd immediately worry about, well how did they get there, but also about pathogens, right? How do you prevent the pathogens associated with those things from killing you? What we're doing here is collecting the ants, but also collecting some of their garbage, and what we wanna do is figure out if in that garbage there's a fungus which could be as useful as an antibiotic, but also that the ants might be using to break down what's the waste in their colony. In the lab, Anne Madden recovers the fungi found on the ants, opening the window to a previously unseen world. So this is my favorite part, because you never really know what's going to grow from these insects on a Petri plate. It's crazy diversity for one insect. That's awesome. We're seeing different fungi here, but it's likely that there are more species here than we can even see. My biggest hope is that this has got antibiotic producing fungi in it, this has got fungi we can use to clean up human waste, yeah I guess we don't know what these are yet, right? Right, so we have to do further genetic sequencing to find out who they are so that afterwards we can find out what they do. It makes me antsy not to know . Is that too much? Yeah, sorry. We've barely begun our journey into the mysterious fungal kingdom. There are wonders to be discovered wherever we search. So if we look to many of our problems, and we think about what the challenge is, fungi offer a vast reservoir of possibilities. Both because of their mastery of chemistry, and because of their diversity. Fungi are nature's great survivors. This makes them both powerful allies, and given the chance, formidable foes. An unfolding epidemic on Canada's west coast is a warning of fungi's lethal power. In 2001, vets on Vancouver Island noticed something unusual. Many cats and dogs developed lumps under their skin, and were having trouble breathing. (phone rings) Good afternoon, Dr. Ghesquiere's office. Soon, people began complaining of stubborn coughs, headaches, and night sweats. X-rays showed shadows on their lungs. They thought they had cancer, they were told that by their surgeons, and so they'd cut it out, and lo and behold it was not a cancer, it was a fungal infection. The culprit turned out to be cryptococcus gattii, a relatively harmless fungi, previously only seen in tropical environments like Australia. The question was how did it get here, we did not know. And this is where we've bit of a detective story to sort that out. What we are really looking at when we are looking at fungi is evolution itself. Professor Bartlett is a microbe hunter. When c. gattii emerged, it was her job to locate it in the wild. There was no time to lose. C. gattii had already infected hundreds of people, killing nearly one in 10. Once we knew that it was gattii, then we contacted our Australian colleagues where it's endemic, and primarily associated with eucalyptus trees. It gave us at least something to go on, the trees. And that was our initial starting point, but I was also taking air samples, and that was actually the big break through. All you really need is to get the spores airborne, and there's no way of controlling them. With an infection rate of 10 times higher than in Australia, Vancouver Island was declared a hot zone. Standing in the middle of these trees, in the middle of literally a forest, and not knowing whether it was going to be epidemic curve, it was pretty sobering. The second thing that crossed my mind at that point was that because I was the one there taking the samples, was if I had a risk of coming down with cryptococcal disease or not. What made gattii scary was that it infected healthy people. It's very, very unusual. Left undetected, the infection can be lethal. Ken James, a former mill worker from Duncan, was lucky. His life was saved by coincidence. ...Center for Disease Control is issuing a health warning. Here are the symptoms to watch out for. They were doing a report on this cryptococcus disease on Channel 6 News out of Victoria. They started going through the symptoms, and I was like, yup, check, check, check, and basically I had pretty much all of the symptoms that it described. ...undiagnosed fever, night sweats, neck stiffness, and severe-- Dr. Ghesquiere got a sample, took it and cultured it, and came back and said that I did in fact have cryptococcus. Invasive fungal infections are difficult to treat, and early diagnosis is essential. It's very hard to treat them. To give you an example, if you have bacterial pneumonia, you can often be treated for two weeks and you get better. When you have a fungal disease, you often have to treat for many months. I was on the medication for a year. Had I not seen that TV show, I might not be here talkin' to ya today, right? I mean, people have died from it. Not everybody is as lucky as Ken. The infection can get lethal when the fungus finds its way from the lung to the brain. You've got this fungal infection that would surround your brain, and in some people would actually invade the brain tissue. And so we can see small lesions that would look like holes, Swiss cheese in their brain. But how can a harmless yeast that enjoys a simple life in soil, find a way to invade and kill healthy humans? It's because the ecology of the soil. There are other organisms there, including amoeba, soil amoeba. Now, they are animals, they do move around, and they eat other organisms for their food source. In this evolutionary arms race, c. gattii built a protective shield to avoid being eaten. Now, shift that whole concept to the human body. As humans, we have a primary defense system that it's called white blood cells. And if you were naively looking at them under the microscope, they don't look a whole bunch different than soil amoeba do. Much like amoebas in the soil, our white blood cells, the macrophages, engulf invading microbes. But c. gattii is equipped to deal with such a challenge. The same traits that allow them to survive amoeba, allow them to survive macrophages in the lung. Long before the first human, this fungus had evolved the means to kill us should we cross paths. Probably would have lived out his happy little life without our even knowing it was here. Cryptococcus gattii lay dormant in the environment until conditions changed, and the change was global warming. We know that over the last 40 years, the average mean temperature has gone up by a degree or two in this particular area. We have longer dry spells, and so as soon as you get that dust stirred up, the possibility of people inhaling the (mumbles) goes up, and so the possibly of people coming down with cryptococcal disease goes up. C. gattii is on the move. It was localized to Australia, then in a blink of an eye, this becomes a world wide problem. It's spreading to United States, and we think that this has established itself in this continent, and we're gonna be seeing a lot more of it. The Vancouver outbreak is a cautionary tale in a warming world. Given the opportunity, fungi are always ready to invade new territory, including us. It has only been by very good fortune that humans in general have only a few pathogenic fungi because there are only a few pathogenic fungi that can grow at 37 degrees, IE, human body temperature. That's been our savior. But as the planet warms, more and more fungi are forced to adapt to new conditions. Therefore, organisms are out there, but are not capable of causing disease today because our temperatures keep 'em out could become new pathogens. Fungi will continue to evolve in unpredictable ways. To ignore them is both a lost opportunity, and a dangerous mistake. And so I think it's more important than ever to understand what this relationship we have is with fungi because we don't have control over them and we're hoping that we can keep this mostly peaceful relationship going. Since the dawn of life, fungi have been the driver of evolution on land. They ate the rocks that created the soils and nurtured plants, turning the planet green. To have the planet that we have today, we had to have fungi. It was fungi that brought back life after each global catastrophe. If there were no fungi there would be no other life. They're a keystone in our world. It was fungi that paved the way for civilization. They have made us who we are. All around here are these fungi that are falling on you that are going to alter our fate as humans, and we're just starting to figure it out. And as we begin to explore the kingdom of fungi our most exciting discoveries are still to come. (birds chirping) (wings flapping) |
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