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[MUSIC PLAYING] JACOB BENEDICT: Hi. I'm Jacob Benedict, and I'm here to talk to you today about fungi and how they're in the world around us. Organisms are divided into five different kingdoms. These kingdoms consist of things like plants and animals, and one kingdom is called fungi.
What makes a fungi different from some of the other kingdoms, like animals and plants, are a few qualities that are kind of a little bit biology but they're kind of easy to understand once you start to think about them. The first difference heterotrophs and autotrophs. Now, these might sound like big words, but at a basic level it means where they get their food from.
As you probably know, plants make their own food through photosynthesis. On the other hand, animals have to consume other organisms to get their food. And in this respect, fungi are a lot more like animals. Fungi are called heterotrophs, which means they get their food from other sources. You've probably seen a fungi on a log before. And this is just the fungi decomposing the wood and getting its nutrients from it.
Another thing that makes fungi a separate kingdom from plants and animals is at a cellular level. Now, if you've ever seen a cell, sometimes they have a thing around them and it's called a cell wall. And it's pretty much a hard structure. Plants have cell walls, and so do fungi.
If you look at an animal cell on a microscope, on the other hand, they have more of a loose structure. It feels a lot more like skin then it would like wood. And that's called a cell membrane. So fungi, because they have cell walls, have to be characterized in a different kingdom than animals.
I bet you think all fungi are mushrooms. In fact, most fungi never even turn into mushrooms. Mushrooms are a fruiting body for fungi, and it's basically a reproductive structure. So most of the time in nature, fungi are this little mycelium structure that you see in mold.
Mycelium sounds like a big word, but you've probably seen it before. It's the fuzz that you see growing whenever there's mold on bread. Lots of mycelium gets together and make this fuzz. And this is what most fungi are in nature.
Fungi have some bizarre reproductive techniques. Unlike plants and animals, fungi can reproduce both sexually and asexually. What this means is, in the absence of a partner, fungi are still able to reproduce. When two fungi reproduce sexually, they create spores. And these spores, whenever they land in the right environment, will create another fungi. Whenever they reproduce, they have basically the mushroom coming up. And there's three different methods of spore dispersal from that.
The first type of spore dispersal, wind, is something you're probably very familiar with. Whenever you're in your backyard playing and you step on these little balls, they'll release black clouds. These balls are called puff balls, and the black clouds are actually spores. They rely on people like you, and animals, to step on them to release their spores and send them through the wind.
Some fungi rely on animals to disperse their spores. A really gross example of this is the stink worm fungi. What happens with the stink worm fungi is, it sprouts its mushroom and then it starts smelling like rotten flesh. Now of course, flies are attracted to this. When the flies land on it, spores get on their legs. The flies then go to other fungi and disperse the spores.
Some fungi utilize water to disperse their spores. A really cool example of this is the bird's nest fungi. If you imagine a little bird's nests with four or five eggs in it, this is what the bird's nest fungi looks like. And when a water drop comes down, it hits the bird's nest, or the cup, and dispersing the eggs a few feet. Now, this may not sound like a lot, but whenever the fungi is about this big, that's actually quite an effective means of dispersing.
Now I want to tell you about some really bizarre types of fungi. The pilobolus fungi definitely has a unique issue to overcome. It only lives in cow poo. So in order to reproduce, it has to be eaten by a cow again. But a cow won't eat anywhere near where it just pooed.
So what happens is, the fungi-- its hyphae, actually, which is about the size of your hair-- has to shoot the spore 16 feet outside of the poo so that the cow will eat it again.
The fungal kingdom actually has the honor of having the largest organism on earth. Now what this is is a colony of honey mushrooms in Oregon. It covers 3.5 square miles, which is 1,600 football fields. It's basically a net covering the span with thousands of mushrooms popping up around it. Scientists started looking into this whenever they noticed trees were dying because this mushroom was just sucking the life out of it. They've estimated it to be 9,000 years old.
Fungus came onto the world stage in a pretty bizarre way in 1993. The Chinese women's track team actually broke five world records that year. Now, whenever the debate ensued, the coach had told reporters that they ate Chinese caterpillar fungi. Now what these are, are fungus that parasitize caterpillars, and they're dried up. In China, these are a delicacy and trade for about $20,000 a pound. Reportedly, these fungi can give superhuman stamina, and that's how the runners broke all the records.
Fungi, like lots of other types of organisms, can actually be bioluminescent at times. Now, what this means basically is, they can glow in the dark. One species, called fox fire, might be pretty alarming if you saw it at night. It glows bright green. And actually, Benjamin Franklin thought of the idea of using this as a flashlight on early submarines.
The fungal kingdom actually has some pretty potent killers. The death angel, which looks just like portobello mushrooms that you might have had on pizza, can kill you in under 24 hours. It causes 95% of fungal deaths, and is in backyards all throughout America.
Ringworm, the disease that grows underneath your skin, is actually not caused by worms. In reality, it's caused by fungi. And the reason why it grows radially is because fungi also grow in a circular pattern outwards.
Another fungi that you may have encountered is toxic mold. Now, what happens after floods, a lot of times, is black mold will grow in someone's basement. And you actually have to condemn the house after that.
While fungi can cause disease, they can actually cure them. Alexander Fleming, a scientist, was growing bacteria in his lab. He accidentally left the lid off of one of the Petri dishes, and fungi grew on it overnight. He was very upset, but whenever he looked closely, he realized that around the fungi, all the bacteria had died. This led to the discovery of penicillin, the antibiotic that has saved millions of lives.
Fungi play a pretty key role in the development of some other pretty important drugs. One is cyclosporine. Now, whenever someone gets an organ transplant, to prevent rejection from the donor, they have to take an immunosuppressant that's made from a fungi.
You're probably pretty familiar with mushrooms as a food source. We'll start off with some really familiar ones. This is a button mushroom. This is a crimini mushroom, and this is a portobello mushroom. Now, you might think they're all pretty different looking, but in reality, there are all the same species. Just with different characteristics.
These mushrooms are examples of cultivated mushrooms. What this means is humans are able to domesticate them, and then grow them in controlled environments, unlike a lot of mushrooms that you'll see at the grocery store.
So some other types of mushrooms that humans have been able to cultivate are beech mushrooms. And you can tell their cultivated by looking at the bottom of them. Another type is the oyster mushroom. Both of these are grown on log-type substrates.
Shitake mushrooms, are the final type of cultivated mushrooms I'll talk about. You could actually grow these in your own backyard. What you do is drill holes in a log and put shitake spores mixed with sawdust in them, and cover it with wax. Nine months later, you could have a log filled with shitakes.
This bizarre-looking fungi is called hen of the woods. And this is a type that isn't cultivated. Now this means is, whenever you see this in the grocery store, someone had to go out in the woods and actually pick it.
Yeast is a type of fungi that you're probably pretty familiar with. Again, this is a fungi that doesn't produce mushrooms. You've probably seen this package in your refrigerator before. And this is what's used in bread making.
Another type of yeast is used in beer and wine brewing. And this is what actually makes the beer alcoholic.
Another type of yeast is used in the production of marmite. You might have heard this called vegemite before. This eaten a lot in the UK and over in Australia. What this is, basically, is yeast extract paste. And it has a pretty potent taste.
Fungus is used in the brewing of some pretty familiar products. One is soy sauce. Fungus is actually used in the fermentation process used to make soy sauce. Another product is called kombucha. And if you actually look at the bottom of a new bottle, you can see fungus at the bottom.
Some products that are starting to become pretty popular are made using fungi. One is tempeh. Now what this is, is basically puffed rice with fungus growing all around it. And if you look really closely, the white fuzz is fungi.
Another product is called Quorn. And this is basically compressed mold. And what it comes out looking like is a chicken nugget. And it tastes just like chicken.
Fungus is used in the making of some pretty familiar cheeses. One is blue cheese. If you look really closely, you can see blue fungi growing on the inside of the cheese. This fungus is actually really closely related to the fungus that makes penicillin. Another way fungus shows up in cheese is on the outside. If you look at this wheel of brie, you can see white fuzz on the outside of it.
In Mexico, people eat some pretty bizarre fungi. One of them is corn smut, or huitlacoche. Now what this is basically a fungal growth on corn ears. And people take them off and make things like dip from them.
You probably eat fungi every day and don't realize it. Citric acid is made using fungus. Citric acid is an ingredient in things like tomato sauce, candy, or anything processed. It's added to these foods to give it a sour flavor.
As you can see, fungi are in our backyards, in the medicine we take, and the food we eat. They're not that bad after all.
[MUSIC PLAYING]
Jacob discusses fungi, its impact and its uses in the world around us. He talks about the difference between "fungi" and the other four Kingdoms: Bacteria, Archaea, Plants, and Animals.
