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  • OK, now here's a question.

  • What's the biggest living organism on the planet?

  • A whale? A redwood tree?

  • Arguably it's armillaria,

  • a huge honey fungus living in a forest in Oregon, USA.

  • It covers over nine square kilometres

  • and is thought to be at least 2,400 years old.

  • Oh, and it glows in the dark.

  • Mind blown?

  • What if we also told you that other types of fungi

  • can absorb oil spills, control insects' brains

  • and that fungi in general

  • are essential to all terrestrial life on Earth?

  • And there's still so much we don't know -

  • more than 90% of the fungi in the world

  • are currently unknown to science.

  • You could say there's mush-room for learning.

  • Now that we've got that terrible pun out of the way,

  • we can take a closer look

  • at some fascinating facts

  • that will make you a real fun-guy at parties.

  • Sorry.

  • If you think of mushrooms as vegetables on your pizza,

  • you're not alone,

  • thanks to the Victorian botanists who classified fungi with plants.

  • In fact, fungi are neither plant nor animal.

  • They are in a kingdom of their own,

  • but are genetically much closer to animals.

  • The genetic code of a mushroom

  • has more in common with ours than a potato's.

  • Maybe don't mention that to your vegan friends.

  • Fungi also have the ability to control other organisms.

  • While some species of fungi break down dead leaves and wood,

  • like the helpful housemate

  • who always remembers to take the bins out,

  • other fungi are mycorrhizal,

  • they plug into the root tissue of plants

  • and pass precious nutrients between them.

  • This process forms a dense fungal network called a mycelium.

  • Soil often contains masses of these mycelial threads

  • connecting different plants, like fibre-optic cables.

  • In woods, the network is known as the wood-wide web

  • because plants use it to communicate with one another.

  • In a fertile pasture, the fungi feeding on plants below ground

  • can be many times heavier than the cows eating the grass above it.

  • Some fungi get other species to do the work for them.

  • The Leucoagaricus uses chemical signals to 'employ' leaf-cutter ants.

  • The ants work together to form a supply chain

  • that can deliver up to 60,000 leaf fragments an hour to the fungus.

  • In return, it produces miniscule ant-sized mushrooms to feed them.

  • Other fungi employ more gruesome methods.

  • Cordyceps infiltrate their insect host -

  • for example ants or beetles -

  • and control their brains,

  • forcing them to climb up high,

  • and then bursting out of their bodies to scatter their spores to the wind.

  • Talk about evil genius.

  • Not content with insect mind-control,

  • some types of fungi can trouble humans,

  • causing irritations like athlete's foot,

  • as well as the more deadly histoplasmosis.

  • Ergot, a fungus that grows on wheat and rye, can literally send you mad -

  • eating bread made from affected flour

  • is likely to have contributed to mass hallucinations in medieval Europe.

  • And you don't have to be a seasoned forager

  • to know that some species of fungi are highly toxic.

  • If I were you, I'd avoid anything with an intimidating biker-gang name

  • like Autumn Skullcap or Destroying Angels.

  • While fungi can, in some cases, be extremely dangerous,

  • they are also an invaluable resource.

  • For a start, fungi produce life-saving medicines

  • such as penicillin.

  • Yeast is a fungus,

  • without which we'd have no bread, wine, beer or cheese.

  • Even Quorn is made from a fungus.

  • Basically, without fungi there would be no middle-class dinner parties.

  • Mycelium can be used to make packaging and clothing.

  • Fungi have been used to clean up oil spills,

  • and an itaconic acid derived from a fungus

  • is even used to make Lego!

  • Fungi are also eco-warriors.

  • They are absolutely essential to a healthy soil,

  • and play a key role in trapping CO2 fixed by plants into the soil,

  • preventing its return to the atmosphere.

  • Over a thousand billion tonnes of carbon

  • are locked in the world's soils.

  • That's more than twice the amount of carbon

  • held by all the trees on Earth.

  • If the activity of soil fungi were to increase,

  • they could potentially solve global warming on their own!

  • But despite their many uses, and dangers,

  • of course fungi aren't actually 'good' or 'evil'.

  • They are an incredibly adaptable and distinct life-form,

  • playing a key role in terrestrial life on the planet.

  • And for that -

  • and not just because they taste great on pizzas -

  • they should be celebrated.

OK, now here's a question.

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The fascinating world of fungi | BBC Ideas

  • 35 1
    Summer 發佈於 2022 年 10 月 23 日
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