Previous: This Ancient Mammal's Ears Were Built for Chewing
Next: The Curious Case of Colic



View count:3,280
Last sync:2019-12-08 17:20
Mushrooms can be pretty weird! Some have the power to trick animals into caring for them, appear to bleed, or even clean up radiation!

Hosted by: Michael Aranda

SciShow has a spinoff podcast! It's called SciShow Tangents. Check it out at
Support SciShow by becoming a patron on Patreon:
Huge thanks go to the following Patreon supporters for helping us keep SciShow free for everyone forever:

Kevin Carpentier, Eric Jensen, Matt Curls, Sam Buck, Christopher R Boucher, Avi Yashchin, Adam Brainard, Greg, Alex Hackman, Sam Lutfi, D.A. Noe, Piya Shedden, Scott Satovsky Jr, Charles Southerland, Patrick D. Ashmore, charles george, Kevin Bealer, Chris Peters
Looking for SciShow elsewhere on the internet?

Special thanks to Dr. David Moore's_Mane_mushroom_A_review

[♪ INTRO].

There’s more to mushrooms than the cute button varieties you find at your local grocery store. The word “fungus” describes a whole kingdom of organisms that are neither plant nor animal.

It includes chanterelles and shiitakes, but also molds and yeasts. Mushrooms are the part of the fungus that spreads its spores in order to reproduce. And there are some really strange examples of fungi and their fruiting bodies out there.

They’re not just interesting looking, either. Some have the power to trick animals into caring for them, or even clean up radiation. So here are six weird mushrooms and other fungi, and what sets them apart from regular garden fare.

The first fungus on our list has a pretty clever survival technique. The genus Fibularhizoctonia, also known as the cuckoo fungus, hides itself in piles of termite eggs by mimicking their size and color. Its little round balls aren’t technically mushrooms.

They’re actually the fungus’s sclerotia form. That’s a resting state that will eventually sprout a new colony when conditions are right. By making itself look like termite eggs, the fungus ensures it’s safe until it’s time to sprout.

See, termites will pile all their eggs together in one place and groom and lick them to protect them from dryness and infection. By hiding in the heap, the fungal termite balls get the same protection. But it’s not just a matter of looking like a termite egg.

The cuckoo fungus smells like them too. To blend in, the fungi make an enzyme called beta-glucosidase. This same enzyme is made by termite eggs to help adults recognize them.

And in an experiment from 2000, termites didn’t care for glass beads resembling termite eggs unless they were coated in egg-recognition chemicals. Researchers have found that multiple species of fungus can all hide away in the same termite mound; all it takes is looking and smelling similar enough. There’s just one catch to all this protection: the fungal balls can’t sprout with worker termites around.

Researchers think that maybe the termite’s saliva keeps them from growing somehow. When the termites run out of food and relocate to a new colony, they carry their own eggs,and the fungus, with them. And then the fungus can sprout.

It’s a handy way for the fungus to hitch a ride and set up camp in a brand new location before its competitors get there. This next fungus on the list sounds and looks positively frightening. But it turns out, all its weirdness is just a mushroom living its life.

The bleeding tooth fungus gets its name in part from the teeth-shaped structures on its underside. In fact, all members of the hydnoid family of fungi have these structures, not just the bleeding tooth. Most mushrooms use gills or pores to release their spores.

You can easily spot the gills if you flip over a portobello. But hydnoids use teeth instead. And the bleeding part?

That dark red liquid oozing from the mushroom’s top is actually because of the fungus’s internal transportation system. See, fungi transport nutrients and water up from the soil through root-like structures called hyphae. Under the right conditions, pressure can build up in the hyphae and push fluid up and out of the pores on the mushroom’s surface.

Although there haven’t been any studies to figure out exactly why the fluid is red, one fungi expert we asked thinks the mushroom might add red pigments to attract insects that help spread its spores; the same insects that are also attracted to red flowers. Not creepy and bleeding at all! One of the other cool things about these fungi is how they get their nutrients in the first place.

Bleeding tooth fungi are mycorrhizal, meaning they form symbiotic relationships with trees like pine or spruce. The fungi get carbohydrates from the trees and, in return, they give the tree nitrogen and phosphorus. And you could say it’s quite an intimate relationship.

The fungus’s hyphae grow as a layer on the outside of the tree’s root tips, actually growing in between the tree’s cells, so they can easily hand nutrients back and forth with one another. I’m not sure I’d be comfortable with having a gruesome-looking fungus latched on to me. But it seems to work out just fine for the trees!

When you think of a wild mushroom, chances are you picture something like the Fly Agaric. And I know we’re supposed to be talking about weird mushrooms, but stick with me. This iconic mushroom is depicted in everything from.

Germanic Christmas decorations to Super Mario. But its recognizability has as much to do with its chemistry as it does aesthetics. See, the Fly Agaric’s name may not actually refer to insects.

Instead, it may be related to an older usage of the word ‘fly’, which could refer to madness or possession. That’s because the world’s prettiest, most stereotypical mushroom has hallucinogenic properties. But they’re also kind of toxic, so just in case we have to say it, don’t.

There are accounts dating back to at least the 18th century, and perhaps much earlier, of European and Asian peoples using the mushrooms in religious rituals. If ingested, the mushrooms cause confusion, dizziness, space distortion, unawareness of time and hallucinations, followed by drowsiness and fatigue. The two main compounds responsible are muscimol and ibotenic acid.

They have a chemical structure that’s really similar to the neurotransmitter GABA. And they act in kind of the same way to make neurons in the spinal cord and brain less likely to fire. Which has kind of a calming effect.

But they also explain the mushroom’s psychedelic effects. Muscimol and ibotenic acid trigger the release of additional neurotransmitters dopamine and serotonin, which give those happy feelings. At least that’s what the mice studies have shown.

The funny thing is, these mushrooms are actually trying not to be eaten. Their distinctive red and white color is a warning to animals that, hey, I’m toxic! Seems one creature’s warning system is another’s video game powerup.

This next group of fungi have earned the nickname ‘Hulk bugs’. That’s because they seem to have the ability to absorb radiation. These superhero fungi have been found in areas with some seriously high levels of radiation, like inside the damaged nuclear reactor at Chernobyl and even hanging out on the outsides of spacecraft.

Some fungi on the outskirts of Chernobyl even grow towards the source of radiation. Hence their name, radiotropic fungi; tropism being a term for when an organism turns towards a particular stimulus. But radiation is nasty stuff for most living things, given its ability to shred DNA.

So how can these fungi tolerate it? Some fungi, like black yeast, can protect themselves by using the radiation to activate particular genes related to DNA repair and defense. These fungi seem to have a sensor for detecting UV light, which can also cause DNA damage.

And that sensor may be picking up radiation and turning on DNA repair. And they don’t just absorb it and cope. The radiation actually helps some fungi grow stronger.

For example, when black yeast was exposed to low doses of radiation over 24 hours in the lab, it grew 30 percent more cells, and those cells were larger than the ones that hadn’t been exposed to radiation. And the single-celled fungus Cryptococcus neoformans grew faster when exposed to high levels of gamma radiation in the lab. Scientists think this might have to do with melanin in the fungi’s cell walls.

Yes, the same pigment that gives our skin its color. They think melanin might be acting in a similar way to other biological pigments like chlorophyll to turn radiation into usable energy. When researchers exposed fungi containing melanin to gamma rays, they found an increase in cellular energy production.

But not all fungi found in radioactive areas have melanin, so there may be something else going on that we don’t understand yet. And it would be a good thing to investigate, since some radiotropic fungi may have the ability to decompose and decontaminate radioactive material, meaning they could be used for environmental cleanups. Two fungi are doing just that with the debris at Chernobyl.

But scientists don’t yet whether the fungi retain the radioactive particles or spit them back out into the environment somehow, which is to say, more research is needed to see if they can truly decontaminate radiation. Still, maybe we should rename them Captain Planet bugs? Speaking of names, you can learn a lot about the fungi in this next group from both their scientific and common names.

Their family name, Phallaceae, alludes to these fungus’s distinctive shape. But that’s not the whole story. These mushrooms actually come in a wide variety of forms, from geometric, to alien looking, to something quite beautiful.

Scientists aren’t exactly sure why these fungi take so many different shapes, but some have speculated that it might increase the mushrooms’ surface area to help spread their spores. That’s where this family’s other name comes in: Stinkhorn fungi. They secrete a foul-smelling slime that reeks of rotting flesh thanks to a chemical called dimethyl trisulfide.

The same chemical is given off by necrotic wounds. This attracts flies that gobble up the slime, as well as a bunch of spores. The flies then spread those spores to another location when they poop, helping the mushrooms reproduce.

And it’s not just flies that are interested in this mushroom as a snack. Despite its horrid odor, pickled stinkhorn eggs are a delicacy in China and Europe. One species, the bridal veil stinkhorn, is dried and eaten on special occasions in China.

Once dried they apparently smell more earthy, musty or almondy than putrid, and when cooked have a nice umami flavor. So, don’t judge a mushroom by its smell I guess? Lion’s Mane sounds like something you might add to a potion.

And it kind of is. This fluffy, white mushroom is edible; it’s said to have a fleshy texture and seafood-like taste. It’s been used in Chinese medicine for centuries as an antimicrobial, antioxidant and anti-aging supplement.

Claims abound in support of the beneficial properties of the various chemicals found within lion’s mane mushrooms. And there seems to be some evidence to support these claims. One group of compounds, the hericerins, slows the growth of cancer cells.

Another, belonging to a class of chemicals called polysaccharides, stimulates immune responses by activating the body’s defensive cells. And in a double blind study from 2008, elderly people who took tablets containing the dry mushroom powder scored better on a test of cognitive function after 16 weeks than those who received a placebo. But before you start stockpiling Lion’s Mane, you should know there are a few snags.

For one, a lot of these studies were done in vitro, that is, with a culture dish of cells rather than an actual person. And others were done on rodents. There’s a big difference between rodents and people, and between cells and full-blown human bodies, so the effects probably aren’t as staggering as some people might have you believe.

Still, if there’s a silver lining, it’s that this mushroom still tastes pretty good. These magnificent mushrooms and fancy fungi all stand out for different reasons, but it goes to show that there’s a lot more going on than what’s in your backyard. Unless there’s stinkhorns in your backyard.

Those things smell terrible. I’m so sorry. Thanks for watching this episode of SciShow.

If this list piqued your interest, there’s a whole episode of our spin-off podcast SciShow Tangents about the fungus among us. And that’s just one of the lightly competitive, science poem-filled topics on offer. It’s brought to you by the same super smart people who make SciShow, as well as Complexly and WNYC Studios.

Check it out wherever you find podcasts. [♪ OUTRO].