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Psychedelics, mind control, radiation-eating: The secret superpowers of fungi - Max G. Levy
Psychedelics, mind control, radiation-eating: The secret superpowers of fungi - Max G. Levy
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Phụ đề (83)
0:06
When scientists sample the soil, bodies of water, or even the air for DNA,
0:13
they routinely unmask thousands of tiny mysteries—
0:17
unique fragments of fungal DNA that don't match any known species.
0:23
This DNA belongs to cryptic organisms, often referred to as “dark fungi,”
0:30
which, like dark matter and dark energy,
0:33
are simultaneously all around us and yet elude discovery.
0:38
Scientists estimate that somewhere between 2 and 12 million species of fungi
0:45
remain undiscovered—
0:47
their physical structures yet to be seen,
0:49
either because they’re microscopic, live hidden within other species,
0:54
or for other unknown reasons.
0:57
The diverse fungal kingdom,
0:59
which includes everything from baker's yeast to edible mushrooms
1:03
to foot infections,
1:05
has long defied assumptions.
1:08
For centuries, biologists mistakenly classified them as plants,
1:13
for what they’d argue were good reasons:
1:16
many grow from the soil atop branching, root-like networks.
1:20
But at the biological level, they're very different.
1:24
Unlike plants that harness energy from the Sun,
1:27
fungi eat by decomposing matter or siphoning nutrients from other organisms.
1:34
Rather than cellulose, their cell walls are made of chitin,
1:38
the same material in exoskeletons of insects, like beetles,
1:43
and crustaceans, like shrimps.
1:46
Fungi are actually more closely related to animals than plants,
1:51
sharing a common ancestor
1:53
which first appeared over 1 billion years ago.
1:58
Over time, fungi evolved to occupy a range of ecological roles,
2:03
including intertwined relationships with plants.
2:07
Many plants can't survive without these fungal partners.
2:11
Ectomycorrhizal fungi envelop plant roots,
2:15
trading nutrients they forage in the soil, like phosphorus and nitrogen,
2:20
for carbon to fuel their growth.
2:23
Another guild, called arbuscular mycorrhizal fungi,
2:27
goes so far as puncturing plant root cells like straws to aid in this exchange.
2:33
This relationship enabled plants to colonize land 470 million years ago,
2:40
when nutrients were far more difficult to obtain from the barren, rocky ground.
2:46
Other fungi evolved remarkable strategies to defend against, exploit,
2:52
and manipulate their neighbors,
2:54
often by producing an arsenal of compounds
2:57
like antibiotics, toxins, and even psychedelics.
3:02
Many mushrooms in the genus Psilocybe produce psilocybin,
3:06
a molecule that binds to serotonin receptors
3:09
in the bodies and brains of animals.
3:12
This causes hallucinogenic effects in humans,
3:16
though psilocybin likely evolved to deter hungry slugs or snails.
3:21
Clathrus archeri, a cluster of red tentacle-like mushrooms,
3:26
sometimes called “devil’s fingers,”
3:29
emits a sticky, spore-filled slime called gleba.
3:34
It smells like rotting flesh,
3:36
attracting nearby flies that feed on it and carry spores away on their bodies.
3:42
Other fungi take a more extreme approach.
3:45
Many species of Cordyceps infect ants,
3:49
chemically hijacking their nervous systems with toxins
3:53
and connecting directly to muscle fibers to puppeteer their movements.
3:58
The infected ants become zombies,
4:00
compelled to climb to high places and eject millions of fungal spores.
4:07
Still other fungi are more self-reliant,
4:10
carving out solitary lives in extreme environments,
4:13
like the walls of nuclear wastelands.
4:16
Researchers have observed at least 37 species of fungi
4:20
living among the ruins in Chernobyl,
4:23
home to one of the world’s worst nuclear disasters.
4:26
Many are rich in melanin,
4:28
a pigment that can absorb harmful radiation to protect fungal cells and DNA.
4:34
But some don’t just endure radiation— they eat it.
4:38
Studies conducted on the International Space Station revealed
4:42
that species like Cryptococcus neoformans can convert absorbed gamma radiation
4:49
into useful energy,
4:50
establishing a previously unknown metabolic strategy,
4:54
and redefining the perceived limits of life.
4:59
The planet-wide consequences of this fleet of fungal functions
5:03
are still making themselves known.
5:06
In the Arctic tundra, fungi form a vast underground network,
5:11
helping plants survive the harsh winters,
5:14
while stockpiling carbon from the atmosphere.
5:17
Scientists suspect these soils may be particularly rich in rare, dark fungi.
5:24
And these fungal networks, along the plants they support,
5:28
may sequester about 1 trillion metric tons of carbon—
5:32
10 times more than the entire Amazon rainforest—
5:36
potentially keeping Earth resilient against climate change.
5:41
The fungal world we see is vast and wild.
5:45
Who knows what other wonders might be growing just beyond our view.
