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Giant, fungus-like organism may be a completely unknown branch of life
- ahazred8ta 2y agoPrototaxites, an ancient treetrunk-mushroom-like organism that preceded land plants about 400M yr ago. Its fossils contained plantlike lignin instead of funguslike chitin or chitosan. https://www.biorxiv.org/content/10.1101/2025.03.14.643340v1 https://www.biorxiv.org/content/10.1101/2025.03.14.643340v1 https://en.wikipedia.org/wiki/Prototaxites https://en.wikipedia.org/wiki/Prototaxites
- Liquix 2y agohilarious: John William Dawson, a Canadian scientist, studied Prototaxites fossils, which he described as partially rotten giant conifers, containing the remains of the fungi which had been decomposing them. This concept was not disputed until 1872, when the rival scientist William Carruthers poured ridicule on the idea. ... Dawson fought adamantly to defend his original interpretation until studies of the microstructure made it clear that his position was untenable, whence he promptly attempted to rename the genus himself, calling it Nematophyton ("stringy plant"), and denying with great vehemence that he had ever considered it to be a tree.
- therealpygon 2y ago[flagged]
- qbxk 2y ago> Prototaxites did not contain chitin, a major building block of fungal cell walls and a hallmark of the fungal kingdom. The Prototaxites fossils instead appeared to contain chemicals similar to lignin, which is found in the wood and bark of plants. ... best considered a member of a previously undescribed, entirely extinct group of eukaryotes So these are the ancestors of Groot? or Ents? and all manner of "animated trees"?
- N_A_T_E 2y agoPretty sure this was a major plot point of the latest resident evil game.
- andrewstuart 2y agoThere’s one of them at the back of my fridge.
- mfdoom13 2y agoCommon Side Effects, here we come.
- chasil 2y agoI'm still trying to wrap my head around nitroplasts, another newfound plastid.
- deadbabe 2y agoIs there a point in Earth’s history where if you were to visit you’d find it was just a fungus planet, with no other form of life? Could there have been fungal type creatures that lived, died, and left no trace?
- doctoboggan 2y agoNo, non-fungi single celled organisms have existed at all times that fungi have existed on earth.
- adrian_b 2y agoBlue-green algae have colonized fresh water and all moist spaces on the continents billions of years before the appearance of fungi and of the terrestrial green plants. They were accompanied by the ancestors of several groups of heterotrophic bacteria, e.g. Firmicutes and Actinobacteria (the Gram-positive bacteria), which had developed abilities like making spores that could survive dryness and be spread by wind, like also fungi would do later. In fact, it is likely that blue-green algae have appeared for the first time on continents, either in fresh water or moist rocks, and only much later they have spread into marine environments, which had been previously dominated by anoxygenic phototrophic bacteria, which were oxidizing sulfur, iron or manganese, not water. The transition to oxidizing water is likely to have been necessary for the spreading of the blue-green algae on continents, where the fresh water had only a very small content of substances that could be oxidized unlike seawater, which at that time was rich in hydrogen sulfide and in Fe(II) and Mn(II) ions. When the blue-green algae have expanded back into the oceans, that must have been after the oxygenation of the atmosphere has modified the composition of the oceans, by precipitating most of the iron and manganese and oxidizing sulfide to sulfate, which would have deprived the anoxygenic phototrophic bacteria of their food. Then, in the oceans, at some point in time a blue-green alga has become symbiotic with the ancestor of red algae and green algae, which have then dominated for many hundred million years the oceans, before the much later appearance of other phototrophic groups, like diatoms and brown algae. Multicellular red algae and green algae already existed in the oceans around one billion years ago, when no other multicellular eukaryotes existed. When the fungi have appeared through a transition to a terrestrial lifestyle, that could happen only if on land they could find great amounts of dead living matter, which had been produced by blue-green algae. It is not known for sure whether fungi have appeared a long time before the first terrestrial green plants or about the same time, but it seems that already for the most ancient terrestrial green plants, symbioses with fungi that enhanced the absorptive capabilities of their roots have been important. For aquatic plants, roots had only a fixation function, not the function of absorbing nutrients, so perhaps symbiosis with some already existing terrestrial fungi might have been necessary, not optional, for the first terrestrial green plants, until better absorbing roots have evolved. So for a long time in the history of the planet, the drier parts of the land would be barren, but wherever there was moisture you would find mats or crusts of blue-green algae, with associated heterotrophic bacteria and viruses. Then, probably not earlier than the Cambrian, there would be also fungi, and even later the first moss-like terrestrial green plants would appear.
- calibas 2y ago> with eukarya containing all multicellular organisms within the four kingdoms of fungi, animals, plants and protists. This bugs me so much. The four-kingdom system should have died out decades ago, it's absurdly wrong. For one thing, fungi and animals should be together (opisthokonts) if you're dividing eukaryotes into the major groups. If you consider genetics, there's no such thing as "protists", they're just a whole bunch of small things that were grouped together because we didn't know otherwise. It's more like, Archaeplastida, Excavata, SAR supergroup, Amoebozoa, and Opisthokonta at the moment. The exact list is up for debate, and currently undergoing change. There's plenty of weird things like Hemimastigophora and we're not really sure where they fit yet.
- mmooss 2y ago> The exact list is up for debate, and currently undergoing change. My strong impression is that even the roots of the tree are debated, with competing models that often change. > The four-kingdom system should have died out decades ago First, hopefully not! :) Second, I think it's used because it's the last stable model. Third, it's a model that the public can understand - theres no point in even trying to use "Archaeplastida, Excavata, SAR supergroup, Amoebozoa, and Opisthokonta" unless you are an expert in phylogenics or evolution. Who can understand and remember that?
- calibas 2y agoChildren can memorize all 50 US state capitals, they can memorize a handful of scientific names. If we really wanted to, we could teach them a much more accurate view of the tree of life. Also, I don't think the four-kingdom system has been taught in schools for a while? I went to high school in the late 90s and it wasn't taught then. It's strange to see people promoting it online in 2025. If adults want to remain ignorant, so be it, but at least teach children the truth. Let them know that life is incredibly complicated, it's a mystery we're still solving, and they could be the ones to help figure it out. Don't overly simplify things for small minds, it creates a false picture and it kills the imagination.
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- mmooss 2y ago> All life on Earth is classified within three domains — bacteria, archaea and eukarya — with eukarya containing all multicellular organisms Single cell eukaryotes also exist. Is it strictly true that there are no multicellular prokaryotes (what they call bacteria) or archaea? No exceptions at all?
- dragonwriter 2y ago> Single cell eukaryotes also exist. Yes, "with eukarya containing all multicellular organisms" does not mean "all eukarya are multicellular organisms" it means "multicellular organisms are a subset of eukarya". > Is it strictly true that there are no multicellular prokaryotes (what they call bacteria) or archaea? First off, "prokaryotes (what they call bacteria)" is incorrect. Both archaea and bacteria, in the three-domain model referenced in the article, are prokaryotes. Second, correct, everything understood as a multicellular organism -- as distinct from colonies of unicellular organisms -- is composed of cells with nuclei, classified in eukarya in the three-domain model. (There is a newer proposed two-domain model which disposes with Eukarya as a top-level domain, folding it under Archaea; in that model, clearly, there are multicellular Archaea.)
- mmooss 2y ago> Both archaea and bacteria, in the three-domain model referenced in the article, are prokaryotes. I suppose it depends on which model you use, and as discussed they seem to vary and be in flux right now, but the three domain model I learned was prokaryotes, archaea, and eukaryotes - the first two being different domains. > Yes, "with eukarya containing all multicellular organisms" does not mean "all eukarya are multicellular organisms" it means "multicellular organisms are a subset of eukarya". We agree. I don't grasp your point?
- xdavidliu 2y ago> We agree. I don't grasp your point? your original comment didn't refute the quote, but one needs to squint hard to see that you didn't refute it.
- BrenBarn 2y ago> Upon examining the internal structure of the fossilized Prototaxites, the researchers found that its interior was made up of a series of tubes Who knew the internet evolved millions of years ago?
- exe34 2y agoI love the idea that fungi house the Polises of Greg Egan.
- culi 2y agoit's called the wood wide web (seriously)
- ddejohn 2y agoScientists are so adorable
- amy214 2y agoWho knews the scope and breadth of the reach of Al Gore, internet inventor, conceiver of the series of tubes paradaigm. Perhaps he has a tube all the way back 400 million years ago amongst his tube series https://www.pellcenter.org/did-al-gore-invent-the-internet/ https://www.pellcenter.org/did-al-gore-invent-the-internet/
- bbor 2y agoI saw this on bsky a few days ago and was fascinated, so glad to see it made its way here! I had this question that went unanswered, so hopefully there's some experts/fellow musers here: Why grow up if you don't need photosynthesis? From my perusal of The Literature (AKA an amazing Wikipedia article + the paper discussed in this link), we have a few strong theories about the prototaxites: 1. They fed off decaying matter in the soil through a vast network of mycelia/roots, and didn't photosynthesize. 2. They grew large, trunk-like protrusions, but without any branches or leaves (that were fossilized, at least). Like, way, way taller than the bugs, moss, and short weird proto-grass around at the time. 3. These protrusions were regularly burrowed into by aforementioned bugs, which surely was a major health risk. 4. Even before this analysis, they've always been something of an oddball compared to contemporary life -- so everything's on the table, so to speak. Given those facts, I'm pretty stumped as to what evolutionary pressures might have driven them to grow upwards. At first I considered spore (seed?) dispersal, but mushrooms seem to get along just fine without towering above everything else, and I don't think wind speeds were way lower or anything. Anyone here have any better guesses?
- clort 2y agoWhen you feed off decaying matter, hosting a colony of bugs which go out daily, bring back food and leave waste all around your environment sounds like a pretty good strategy when you don't have any way to move to better pastures?
- boxed 2y agoIsn't this a long time before insects and such though?
- anentropic 2y agoWikipedia says: "evidence of arthropod boreholes in Prototaxites has been found from the early and late Devonian, suggesting the organism survived the stress of boring for many millions of years.[30] Intriguingly, boreholes appeared in Prototaxites long before plants developed a structurally equivalent woody stem, and it is possible that the borers transferred to plants when these evolved" and for Arthropods: "The evolutionary ancestry of arthropods dates back to the Cambrian period." which is about 100 million years before the Devonian also: "The oldest known arachnid is the trigonotarbid Palaeotarbus jerami, from about 420 million years ago in the Silurian period.[82][Note 3] Attercopus fimbriunguis, from 386 million years ago in the Devonian period, bears the earliest known silk-producing spigots" so there could have been all sorts of weird and wonderful bugs burrowing into Prototaxites I guess
- baalimago 2y agoI wonder what it tastes like
- intsunny 2y agoThe article about the study writes: `The study has not yet been peer-reviewed.` We should just stop reading the article then and there. This is a major method of how a single study can perpetuate fake science and fake news.
- verisimi 2y ago> This is a major method of how a single study can perpetuate fake science and fake news. It's a feature, not a bug.
- 1970-01-01 2y agoClickbait is a bug tagged with WON'T FIX
- jfengel 2y agoWe should, but we don't. People want the news now. They don't want to wait for it to be peer reviewed, or even cursorily checked. There is an infinite maw for information, and it has already consumed every single known fact. If you want science, you'll wait a month, because it's not actually urgent. These species waited hundreds of millions of years and it'll still be there in a few weeks. If you want entertainment, you want it right this instant. And that's what LiveScience exists to do. So you really should have stopped reading as soon as you saw the URL.
- countWSS 2y agoPerhaps its a Ediacaran biota remnant, that had very diverse groups some of which could be misclassified because the consensus is against Ediacaran relics existing past their period.
- neuroelectron 2y agoIt's likely simply a fungus that used lignin instead of chitin. It went instinct when fungus learned to attack lignin.
- hydrogen7800 2y agoDiscussions about classifying the domains of life aside, this article implies that there was, or could have been entire domains that are now extinct. Is this the case?
- andrewflnr 2y agoThat's really hard to answer without tackling the classification question head on. Do you mean groups that "would have" been considered a domain if humans had been around at the time? Or groups that are in some sense different from other domains to the same degree those domains are from each other? Whether we tag something as a domain also depends on its abundance and/or visibility. I bet if you take dug into microorganisms, you'd find tons that are as different from plants and animals as plants and animals are fun each other. But they all tend to get lumped in as "protists" or something because... we kinda don't care. I wouldn't be surprised if we somehow found out there were a lot of extinct critters in equivalent situations.
- hydrogen7800 2y agoIn my draft reply, I was going to add "is this even the right question", meaning "is the taxonomy more of a human construct than a natural one". It seems the answer is yes. >Or groups that are in some sense different from other domains to the same degree those domains are from each other? This.
- andrewflnr 2y agoI'm not a biologist, and especially not a microbiologist, so you should take what I say with a decent chunk of salt. That said, microbes are so wildly diverse that that version of the question sounds a lot like "are there any big extinct clades of microbes", which, I don't know, microbes are pretty persistent. But probably. As for macroscopic life, there are some Ediacaran critters like rangeomorphs and tribrachidium that (to my knowledge) are not conclusively associated with any existing domain. So who knows about those guys.
- tremon 2y ago
- curtisszmania 2y ago[dead]
- damnitbuilds 2y agoYou never did like my mother.
- riwsky 2y agoOh, that? That’s just Bob. He helps out around the busy season sometimes. Didn’t know this much about his family, though—neat!
- roughly 2y agoAcknowledging this is a pre-print, but it is _wild_ that we can do this kind of analysis on a species that went extinct nearly a third of a billion years before the first hominids emerged. Every now and again I'm reminded of just how far we've extended our sensorium as a species.
- ChuckMcM 2y agoThis was an interesting read, and reminded me how paleo-biology is the closest thing to exobiology we've got. Looking at the different biomes that emerged on planet earth over a billion years feels equivalent to looking at a thousand different planets at the same time. Basically a thousand chance to see what that 'megayear' produced, life wise.