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New research has revealed that fungi—you know, like mushrooms—barter and trade with
other organisms like little stockbrokers.
Basically, there's a whole economy of nutrients right beneath our feet that we are just
uncovering.
And yes, it can be pronounced either fun-guy or fun-gee, don't even start, and their
classification has been difficult, to say the least.
They're eerily more genetically similar to animals than they are to plants or bacteria.
And things only get weirder from there.
Fungi are possibly the most widely distributed organisms on Earth, existing everywhere on
Earth from the North to South Pole.
They take elements like carbon that are trapped in organic matter, and through decomposition,
they process and release those elements back into the ecosystem for other organisms to use.
They can do this by releasing a sophisticated cocktail of enzymes and other helpful chemicals
that allow them to break down organic material outside of their bodies, so that they can more easily
digest the nutrients. This is how fungi cause decay.
But they don't just play an essential role as nutrient cyclers.
See, all living things need phosphorus and nitrogen to live, but not a lot of those elements
exist in forms that are ready for uptake.
We eat plants and other things that eat plants to get enough of our phosphorous and nitrogen,
but where do the plants get it?
That's right: microbes, like bacteria and fungi.
Fungi that work with plants in this way can grow into structures called hyphae: delicate
thread-like tendrils that can push into a plants' roots.
This forms mycorrhizae—symbiotic relationships between fungi and the plants they glom on
to.
And for the record, mycorrhizae refers both to the kind of fungi that do this and the
relationship between a fungus and a plant's roots, so it's a dual-purpose word.
Mycorrhizae can also connect to each other to form incredibly dense, expansive, and interconnected
networks.
Some estimates say there's around 200 meters of mycorrhizal hyphae in just one gram of
typical forest soil.
I mean are you kidding me?
But plants bring something to the table, too.
They have an ability that fungi do not—they can form carbohydrates through photosynthesis.
So in exchange for essential nutrients, plants provide fungi with those tasty, tasty sugars.
This worldwide network of nutrient exchange includes all kinds of microbes, like these
fungi and bacteria that play a similar role, and as a whole, this system has come to be
known as the Wood Wide Web.
And we're not even to the coolest part yet!
New research details just how these nutrient exchanges between plants and fungi actually
work.
It's like zooming in on a business contract.
We thought we knew what it said but then we took a closer look at the fine print and woa
boy is it more complicated than we imagined.
A research team in Amsterdam recently found that these nutrient exchanges may operate
almost like an economy.
When the plants have more sugars to share, the fungi give more phosphorus in return,
and vice versa.
Both parties can 'punish' or 'reward' each other for good exchange rates.
They can even withhold a store of a nutrient until the other party has a better 'offer'.
Building on the results of this work, the team wanted to go even further.
They tagged each of the molecules in question with a fluorescent compound, and then tracked
the tagged molecules using a powerful confocal microscope.
This allowed them to quantify the nutrient transfer from the fungi to the plant root
and, for the first time ever, actually see the transfer of nutrients.
They then began to study flow patterns within the fungus, making videos of the complex patterns
of movement—you can actually see here that the fungus stops the flow of nutrients in
one direction and reverses it, sending them back the other way.
The scientists think this is our first look into how fungi can redirect nutrients in response
to their environment.
It could even be that these oscillations of molecules represent some kind of
communication—could this be how these complex fungal networks transmit information?
A new paper from a separate team used a database of over a million samples to visualize fungal
relationships with their respective plants, revealing distinct patterns in biogeography:
that means that certain areas of the world have a particular ecosystem type that supports
specific plant-fungus interactions.
This is a more macro look at the role fungi play in ecosystems that are defined by their
local climates.
Research into the complex kingdom of fungi could help us better understand how organisms
all over the world—both fungi and their business partners—have evolved and survived
over millennia.
If we pair this nano-scale look at the transfer of nutrients with a larger, more ecosystem-level dynamic
we can better understand how these relationships might change as the climate becomes more unpredictable,
and what that might mean for the plants that we rely on as we look into the future.
Do you want even more on the mind-blowing facts we're discovering about the microbial life
on our planet?
Check out this video here, and make sure you subscribe to Seeker to keep up with all your
fungal news, it just might grow on you.
And as always, thanks for watching, and I'll see you next time.