Submitted by whittily t3_yea30l in askscience
Lots of cool research in recent years into fungal<>tree symbiosis, including example organisms that underpin entire forests. How is it determined that it’s a single organism throughout the system and how is its size estimated?
As far as I know they use DNA to determine that it is the same organism, you take samples from various places and they all have the exact same DNA and about size it is simply a matter of mapping out where the samples are taken
Seems like burden of proof that it’s the same organism would need to be higher than just matching DNA. Isn’t it possible for a fungus to reproduce in ways that multiple organisms would have the same DNA?
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Indeed—the details of what I don’t understand are included in my questions :) appreciate your contribution tho!
In the old days, they'd take samples from different areas and see if they fuse in a a petri dish, which indicates they are the same individual. These days genetic testing is faster and easier though.
So basically you take samples from different areas and map out where the fungus matches out as genetically identical. Once you get an idea of the amount of ground surface it covers, you can estimate total mass by figuring how much fungus mass is in a given square meter of soil (or whatever) and multiplying by the total area.
Having the same DNA is pretty much the thing that defines what makes up a fungus organism.
Fungal colonies are big networks of filaments that spread through the soil (or something else) and grow by cells dividing and making more fungal cells. So if you get the same genetic signature, you know the cells must be different branches of that same fungal network. There's not really "individual organisms" in these fungus the way there is in animals, it's just what is genetically a part of the original colony, or what's a new colony produced by sexual reproduction.
Got it! Thank you for your responses. I need to do a deeper dive into fungal reproduction it sounds like.
Fungi get graded on a curve then compared to animals/plants when measuring total organism mass then. It’s a little like saying all banana trees are the same organism since they’re all asexually reproduced with the same dna.
Well, it's the same as Pando for example. Or coral heads. People don't usually count bananas because they aren't all connected to each other, but the fungus probably is (there's probably no way to verify that, but it's what you would expect)
I get the feeling our current understanding of what fungi really are and do. Is just now beginning to be slightly realized. With the mushrooms we see being only the tips of living icebergs. To a degree that perhaps all life exists on a foundation of, and is supported by a scaffolding of fungal designs. 🤔
[deleted] t1_ity7egf wrote
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