From the Vault: Shrooms Like Cedars in the Devonian Wilds

a little skit for this one with time travelers. At the beginning, the time traveler, for so it will be convenient to speak of him, turned his attention at last the Devonian period. His pale gray eyes shone and twinkled, and his usually pale face became flushed and animated. The calm of morning was upon the world world, and it's greening,

the spring time of the Earth. The environment was arid and warm, and everywhere I walked I observed forests of moss and clusters of shrub like ferns, and horse tails. Amid them crept primitive arthropods and something that looked remarkably like a winged insect, though I did not catch it in the act of flight. But there were no leaves, no true trees to lift a canopy above my head. But what I at first took for primitive conifers proved anything.

But each of these cylindrical giants stood some twenty feet high, and we were a good yard wide. They towered above the Devonian world like skylight pillars, and I observed just a hint of scores carried away from their bizarre heights. I wonder, then, might these organisms be giant mushrooms? But that's when the more locks came at me. The more locks, I said, surely, the more locks existed far in the future. What were they doing in the Devonian? Well, they stole

my time machine and they followed me. But you arrived there in your time, Well, they stole it from the future. But the look time travel is very complicated. No further questions. Welcome to have to blow your mind? A production of I Heart Radios has to work. Hey, are you welcome to stuff to blow your mind? My name is Robert Lamb and I'm Joe McCormick. And in that cold open

we had a little fun with H. G. Wells. The time machine, which of course is a is a wonderful novel, well worth seeking out even in today's uh technically advanced times. I remember liking it when I read it, but I don't recall does he actually go into the prehistoric past. Well, he certainly goes into the far, far future, which is kind of my inspiration for that, because he goes he goes so far into the future that the world is

just an alien landscape. But one of the fun things is that if you travel back far enough in time, you also encounter an alien landscape like that is what the surface world of the Devonian period four hundred million years ago basically was, and so it was irresistible to use the time traveler. Here is a is a way of sort of the magic name what it might be

like to walk amid the strangely strange specimens. That's all this weird Devonian flora and a glimpse in the wild, a living specimen of an organism that continues to mystify us in the past. It's been called a mystery fossil even and that is proto tax i t s. Yes, today we are going to be talking about the world of prehistoric fungus. This is something that I wanted to talk about for a long time because fungus in the fossil record. I think there's actually a lot of interesting

stuff we could explore. But the keystone of today's episode is going to be, Yeah, the fossil remains of these giant stylite organisms from hundreds of millions of years ago that we're the tallest standing things of their time, and we don't know for sure what they were. We have we have better ideas than we used to, and we'll

get into that as the episode goes on. But yeah, try to imagine yourself as a paleontologist digging into the strata from a pure it hundreds of millions of years ago, where there were no trees, there's no there are no forests on the Earth, but you find these six meter high giant pillars of something that was alive. Yeah, and you can see if you look up the images of prototax it t s, you'll you'll see people posing with

the fossil remnants. Uh. And it looks like like a massive pillar or even in the way it's broken in some of these uh, these fossils, it looks like it could be the you know, the neckbone of some of some enormous creature. Like there's an enormity to the fossil uh that that makes it so irresistible. It is a giant of the past, but it is not. It is not an animal, it is it is something else. We don't know exactly what prototax it t s looked like

when it was alive. They are different interpretations of it, but some of the interpretations uh and in resulting illustrations really give it a kind of almost like a gigaresque or love crafty and appearance of something that looks truly like a um like like pillars, like towers, like little mom like not little you know, towering monoliths um and and certainly they were the largest and tallest feature of

the Devonian terrestrial environment. It dominated the early and early Middle Devonian period, though it eventually gives way to the rise of shrubs and early and other early plants in the Late Devonian. But it is, to say the least, a very tantalizing fossil that can continues to be something of a mystery fossil. So to to get to the origin of the fossil find itself, we have to go back roughly a hundred and seventy six years, and that is when in eighteen forty three Canadian born geologist William

Edmund Logan unearthed fossil remnants of Devonian flora. And the classification of the Devonian period, by the way, only dates back to the eighteen thirties, so it was you know, kind of a revolutionary time and just geologic discovery in general. The name of the Devonian, of course, comes from the Devon area in England, where some of these uh fossil

finds come from. So Logan found uh these specimens in the exposed sections of a Devonian rock on the shores of the believe it's gossip a bay in Quebec, and particularly an area is called seal Cove, which he was mapping for coal and other minerals. Well, this fits in with a great Canadian tradition of of awesome fossil sites being discovered in you know, not originally by paleontologists, but by people developing industry and heavy heavy transport and stuff like.

I think about how the the shale beds like the Burgess Shale and the Canadian rockies were originally found because railroad workers who were building railroads through the area. We're finding these stone bugs everywhere, and that eventually attracted the attention of paleontologists to come in and us to gate. Oh yeah, the world of trilobytes, right, and other creatures

of course, which we'll get back to later. So I want to note that one of one of my key sources on the the early history of this fossil find uh comes to us from paleo biologist of Francis Huber of the National Museum of Natural History in Washington, d C. Who wrote a two thousand and one piece titled Rotted Wood Algae Fungus The History and Life of prototax I T. S. Dawson, eight fifty nine. And it's just a tremendous source on

all of this. But it's also very concerned with naming, renaming, and misnaming things, even getting into the various names used by Logan and others to designate the cove in which they found this. But at times it may seem a little tedious if if you read it in full, but UH fair enough citation and uh in miscitation and the illegitimate renaming of things is a vital part of this

fossil's human history. Yeah, well, you know, you've got to get people to agree on what they call things, or it's gonna be a lot harder to talk about them and can become quite a dramatic issue as well. Unraveled here. So, in eighteen fifty five, Logan's Devonian Flora fossils passed into the hands of noted Canadian geologist John William Dawson, who, by the way, the mineral Dawsonite is named in his honor. He was particularly taken by a large specimen with the

with the peculiar interior structure. It resembled a large tree, but under a microscope he became clear that the fossilized tissue was uh solicified, you know, containing an entangled mesh that resembled fungal my cilia. He even noted the mysilia resemblance himself in his writings, but he didn't really explore it further. Uh, I mean, he did not explore the explore the fungal angle further, but he was very interested in this fossil. He traveled to seal Cove himself and

obtained a dish l samples. Okay, so they've found this giant fossilized trunk of something. It looks like it could be the trunk of a tree, but examining it on a microscopic level, it looks more like the texture of fungus than it does the texture of plant matter. Right, Yeah, particularly my cilia and then mysilium is the vegetative part of a fungus. Just reminded everybody. It's a It's a mass of branching vein like hiphe that you'll find underground

or in whatever. The mushroom or the fruiting body is emerging from the mushroom itself is a death emergence. Life is actually thriving beneath the surface. The mushroom comes up to to release spores. Yeah, it's a reproductive organ. Yeah. Now, the way Dawson interpreted this, this this fossil was Okay, we have something that looks like like fungus. So what we have here is probably a rotting conifer tree, you know,

an early conifer tree. It's rotting, it's decomposing. So I'm seeing the decomposed their fungus within the decomposing uh specimen, all of this preserved in a single fossil specimen. Well, that would make sense. It's it is a tree trunk. It's infested with fungal Mysilia type structures, right, and so he gave it the name prototax I T S. Or essentially, first you referring to the U family texas cia, so the U tree right. Yeah, So so the the actual

name is is referring to UH conifer resemblance. So he puts these eyes ideas out there, and then, um, you know, quite as a surprise to Dawson, a Scottish botanist by the name of William C. Carruthers proposed a different interpretation. Uh. He said, well, this is perhaps the fossil remains of a very large algae aquatic or perhaps terrestrial in nature. Algae, of course, can grow in weird places like on ice

and snow. So he declared a new name. He said, Nope, we're not going to call this prototax I T S. We're gonna call this nemato ficus. Okay, but wait a minute. An algae that like a giant fossilized algae the size of a tree trunk. Yeah yeah, I mean that's creepy. Well yeah. One of the things, and this is pointed out by others that have studied, is like, there's basically no non weird explanation for this weird fossil. We'll get to several comments like that later. Yeah, there's no like

normal way of looking at it. Now, Here's here's the thing about Carruthers coming along and saying, no, this is nemo nemato ficus. First of all, there are rules with the naming of things, even at the time, so you're not allowed to just come and give it a new name that it's an illegitimate renaming. So so that alone is kind of weird and and rude. But then also, according to Huber, Carruthers was just scathing and very personal

in his criticism. Quote scathing and slanderous uh in terms of critic as sizing Dawson, and it seemed to have like really caught Dawson off guard. Um, you know, based on these descriptions, one is tempted. I don't do not know much about William C. Carruthers, but but just based on Huber's writing, one is tempted debut Caruthers is something of a bully in his field while also being an extremely respected botanist. But then again, perhaps our our our

vision of this rivalry is incomplete. Well, if that interpretation is correct, he would not be the only legitimately good scientist who also is lacking in manners and hire another so um. According to Huber, Dawson fought for his initial classification, but but then later he ends up rejecting it, apparently even trying to make it seem as as if he

never connected the fossil to conifers at all. And then he himself, in his eight book The Geological History of Plants illegitimately used the name nomato ficus instead of Prototaxi t suh. So I imagine that, at least to the time that Huber was writing in like two thousand one, you don't do this. You don't just like switch the name to something else without a I don't know. I'd imagine a lot of fields have like an international naming committee that if there is going to be a name change,

would have to agree on it or something. Yeah, I mean, it's it's why for instance, uh, like one's fossil that we've discussed on the on the show before U Basilosaurus okay, uh I hear saw us in there. That means lizard, it means king lizard. But it was not. We know now it was not a lizard at all. It was a mammal. But we we we don't go back and change the name in this case. So it's a similar

case here. The name prototax I t stuck and did stick despite carruthers uh notion that we should switch to a different name, and that name also Prototaxids, is still used today but names aside. So Carruthers is pushing this interpretation. Okay, this is not a rotting conifer tree that's full of

kind of fungal infestation. This is a giant alga. So what happens with this interpretation, Well, this becomes the dominant interpretation for a while, and it basically goes unquestioned until nineteen nineteen when one Ah Church brings up the possibility that this is a fungus after all, considering the size is achieved by by certain contemporary fungus specimens such as uh, you know, various woody decomposer fun guy. But this idea

didn't take off. He seems to have coined Huber. Basically, this guy was ignored and the alta interpretation continued with papers in you know his reason it's a nineteen seventy nine and nineteen eighty three, continuing this threat of interpretation, I think it is worth stepping back to just appreciate again the physical form of this thing we're talking about. The fossil records indicate that whatever this was, alga rotting conifer tree, or even fungus, it was huge. You know.

I've seen estimates of a maximum known height of six or even eight meters like twice need to twenty five ft, So you've got a giant six m high stock of whatever it was. So something that was alive at a time when we have no evidence that any vertebrates had yet left the water, there were no trees or anything like that. Yeah, it's it's kind of like it's like a tree. It's not a tree, Yeah, it's a it's a it's a weird column of life that exists before

there should be anything like a column. Yeah, and you mentioned earlier, I think that this would have been at a time where this would have been, without question, the tallest living thing on land. No, no trees, nothing stood above it. And I'm trying to imagine the implications of that if we were to live in this world. Because here's one for you. When you think of the word nature,

what's the first thing that pops into your head? My very person to person, maybe you're not like me, but I think most people, at least in tree filled ecoregions, think trees when they think nature. Yeah, Or you know, even if I you know, I really love the landscape of of say Arizona, which, of course and coke comes as a variety of different environments. But but even if

you're thinking about the desert, you're probably thinking about cacti. Yeah, because like the tallest features in a landscape, I think naturally become definitive of that landscape force. When you think city, you think buildings when you think nature. Again, this might be different for people who live and say like treeless environments. Say if you live in a step or something. But if you live in an area with there are trees, the trees become synonymous with nature. They're the iconic life form.

Like what is the lorax speak for? You know, the the The suggestion is that he speaks for nature, but he speaks for the trees. Because the trees are nature by being the tallest living objects on the ground, you in some sense assume them to be the icon of nature. Itself. So what is this thing? It's almost like you could imagine that if you were to walk around the landscape of this period where these things were dominant, maybe Early Devonian or whatever, this might be your idea of nature.

These giant mounds of whatever they are. Yeah, I mean, they were basically the floral lords of the earth. There was nothing else to rival them. So I think we should explore more the continuing scientific debate about what the prototaxids is. But before that, let's take a break and then we come back. We can delve into mushroom theory.

Thank alright, we're back. So we've been talking about these fossil organisms from hundreds of millions of years ago, known as prototaxids, these giant pillars that used to be by far the tallest thing on land. And there's been this great debate about what these fossils were when they were alive. Was it the trunk of a rotting conifer tree that was full of, you know, fungal fibers. Was it a giant alga or was it in fact a fungus And now we're going to get into the details of the

fungus theory. Yeah, despite the conifer versus allergy past for prototax i t s. The most popular hypothesis at the moment, uh, seems to be the fungus hypothesis. Uh. Not to say they are not criticisms or questions regarding the fungus hypothesis, but it does seem to be the most popular interpretation. A giant six meter tall pillar of fungus right now.

I do think it is important to note that we are not saying giant mushroom per se, because that brings to mind a certain image like Shitaki's shape, Right, yeah, sort of a super Mario Brothers kind of world or um or something that you would see on a on a black light fantasy painting in a room. Um. You know, we're no nobody is interpreting this is is having looked like a straight up um uh you know, cliche mushroom with an airbrush fairy sitting on top of it. Right.

But but basically the fungus into pradition comes comes down to the organism's internal structure. It's composed of interwoven tubes just five to fifty microns across, and this would indicate not a plant but a fun guy alike in or perhaps even an algae. UH. You know, some of this points in that direction here as well. But on this issue I want to turn back to Huber again because this is what he has to say about the algae

interpretation and ultimately UH the move towards the fungal interpretation. Quote. In my opinion, prototaxid S does not have the structural anatomy nor morphology of an alga. Chemo taxonomic analysis by Nicholas concluded that the chemical constituents found in prototax it certain fatty acids quton and subarin, differed from modern algae,

but did not preclude an algial affinity. Lack of evidence of lignified supporting structures in the otherwise weak tissues UH and presumed erect habit would have imposed considerable stress in a terrestrial habitat. The Presence of the compounds associated with a terrestrial habitat raised the possibility that the genus could survive on land, but did not prevent reiteration that the algal affinity was still possible. The anatomy, morphology, and occurrences

cannot be refuted so easily. He also points to UH ninety six transmission electron microscope findings from Rudolph Schmidt Uh and this was a paper titled Septal Pores and Prototaxi s an Enigmatic Devonian plant uh. In this he reveals that sceptal pores are are found here, suggesting fungal affinity. Septal pores are specialized dividing walls between cells, septa found in almost all species of fungi in the phylum Bassidi

of my cotta. He points out that the inherent size of Prototaxi tas has long been a barrier to some when it comes to accepting fungal affinity, and he counters this by pointing out that we have you have various examples of of of quite large contemporary fungi and extensive my silian networks. He poses that perhaps prototaxites itself had a vast underground my silia network as well, but we

just don't have fossil evidence of that mysilia network. But the possible picture here is is fascinating an underground kingdom of prototaxids erecting enormous fruiting bodies high into the air to send its spores on the breeze, spreading its kingdom even wider, which causes me to have deeper thoughts about the role of fungus in the evolution of land creatures and land ecosystems. Yeah, this is the kind of of of of mental image that the real hardcore fungus fans

I think I could really get behind. This is like, this is a pulse statements during right here, I've got a question here. You ever ever wonder why we live on land and not underwater? Um less wet. I mean maybe it seems like a stupid question, but you know I stand by that, Like, why why is it do we live in this evolutionary context land based ecosystems rather than under the water, where we our ancestors came from,

where we very well could have remained. Uh. If you picture life on Earth in the Cambrian period about five million years ago, peek under the surface of the water and you would find lots of life. Oceans swarming with strange armies of scuttling, undulating, bilaterally symmetrical animals, billions of trial bytes. You've got, you know, these extinct bottom dwelling

animals shaped kind of like death metal. Really Pulley's many legged proto arthropods with hardened plates of armor on their backs, but also all these other organisms like the low blegged spiked worm that we call Hallucigenia we've talked about that show before, a group of creatures called Opabinia, which are swimming arthropods with five eyes and a single long hose like probosis tentacle reaching out the front of the head.

It was also the time when complex predator prey relationships probably first evolved, with predators, possibly including the huge creature called Anomala caress. And it was a time of geologically rapid evolution and diversification of marine animal body forms and survival strategies. If you look in the period just before the Cambrian period, which is known as the edi acron period, there you don't find any of this stuff. You find, you know, maybe little indications of soft bodied worms, but

like where are all these animals? And then of course they didn't occur in an instant but on a geological time scale, all these different animal body forms, with all this morphological diversity, it all happens pretty rapidly. But of course it has long been the case that we understood all this was taking place under the water in the oceans, that was simply where the life was back then. Uh, Like, we know from the fossil record that if you go back far enough, almost all archaic life on Earth lived

in the oceans and the Precambrian world. It seems the difference between ocean and land was like the difference between a lush forest and a lifeless desert. In order to survive on land, an animal would have to find a way to tolerate dryness, of course, I mean, that's a

big one, but as well as other threats. You know, direct exposure to radiation from a star, which we now know as sunlight seems nice to us, but if you're not used to it, it's probably pretty bad because it contains potentially deadly UV radiation UM and then perhaps most dawning of all, this would be a barren landscape and environment impoverished of chemical nutrition. Where do you get your nutrition and food from? If you decide to go live up on the land, the land is dry, devoid, sun blasted,

plateau of death. I think from like a you know, Cambrian type period, you could think of land as being like mar ers. You know, like what could live there, what could live there at the time is probably limited to the kinds of things we imagine possibly living on Mars if there is any life on Mars, right, you know, maybe like microscopic bacterial type organisms. So how did our rich, modern world of plants and animals and everything else come about?

What did it take to turn these lifeless protrusions of rocky crust into living, breathing ecosystems. It appears, especially after some research in the past few years, that the answer might well be little tiny sprigs of fungus. That is what it took to make the land livable. Uh. So let's back up a few years. I wanted to mention that I was reading a twenty sixteen Scientific American article about research postulating that the first Earth organism to take

up life on land was actually a fungus. Now, there have been some development since then, but this was back in uh. This was a now extinct fungal organism called Torto tubas u, and I was immediately thinking, I want

a T shirt for my neighbor Torto tubas uh. This is based on research published in twenty sixteen and the Botanical Journal of the Lane and Society, based on physical evidence, including samples from Libya and Chad that were four hundred and forty to four hundred and forty five million years old, and this again would have been a time when the land was basically barren. But these fossils contained evidence of microscopic filaments of fungus that are normally used to leach

chemical nutrients from soil. But this would have been at a time when there was essentially nothing else that we know of living on the land. So what did this have to do with us. Well, land ecosystems, of course depend on soil. Right soil is the life Plants need nutrient rich top soil in order to thrive, and animals need plants in order to thrive. So where did the soil to support the evolution of land to plants come from.

Perhaps it came from early land colonizing fungus like Torto tubas, according to a paleontologist, Martin Smith of Durham University in Britain, he was at Cambridge when he did this research, and he's quoted in this article quote. By building up deeper, richer, more stable soils, Torto tubas would have paved the way for larger, more complex green plants to quite literally take root, in turn providing a food source for animals and allowing

the escalation of terrestrial ecosystems. So the idea here is the fungus is the foothold. It's what creates the opportunity for land to be colonized by life forms evolved from the marine life forms below. I like that the fungus is the foothold. Another for you, right uh, And then also featured in the same article as Smith says, quote, by the time torto tubas went extinct, the first trees

and forests had come into existence. This humble, subterranean and fungus steadfastly performed it's rotting and recycling service for some seventy million years as life on land transformed from simple, crusty green films to a rich ecosystem that wouldn't look

out of place in a tropical greenhouse today. So you go from almost mars to you know, forests and plants, and it's fungus like this towrto tubus that probably helped make the soil to allow that to happen, right because because otherwise to your point, like, it's the difference between the rich complex and perhaps in many cases overwhelming life beneath the waters and the desert of of the surface, and the desert might be a fine If you can flop out there, that might be a good way to

get out of the competition for life and of course all that death it's going on below. Then yeah, there's nothing to eat your you're you're out there away from all your food sources. You're gonna have to flop back down. But eventually, with time you reach the point where there there is food up here, there is the foothold is there, there is there is now a a new domain to colonize and conquer. Right uh So about towards the tubas specifically, I want to say that did it have a mushroom?

Did have a fruiting body like a like a mushroom cap that we know of. At the time this article is published, there was not evidence of whether this fungus produced a fruiting body like a mushroom. So, so if you make you t shirt, I don't know if you can righteously depict the mushroom form for towards the tubas. I don't know. It's maybe got to be like a little microscopic filament. But anyway, so early fungus that colonized land was actually able to mine lifeless rocks and minerals

for some nutrients, and that's also pretty amazing, right. Uh. Generally you need to get your nutrients from other life forms, and of course fungus does decompose other life forms, like fungus helps the rot and recycling process we were just talking about, but it can also extract some nutrients just from the mineral crust of the earth, and using that process can help turn lifeless top soil into something more like the rich stuff you think of in your garden today.

But it doesn't stop there, of course. Once early land plants like liver warts often thought to be one of the you know, earliest forms of land plants, once they come on the scene, plants and fungi also form you know, complex symbiotic relationships with one another. They in different ways,

benefit from each other's presence. I was reading a piece about ah it was based on a CBC documentary about prehistoric fungus, and there was a quote from an associate professor of Plants soil Interactions at the University of Leeds named Katie Field, and she said, ultimately quote fungi helped plants move away from being these marginal, tiny little things on the water's edge into large forests and entire ecosystems. So the fungi paved the way for plants to move

away from the water's edge and colonize the contents. Yeah, like these these essentially become the small scale forests in which the Devonian animals would live things that were essentially like like millipedes and centipedes and uh, you know, early things like mites and so forth, like, you know, a very small scale life. But they need an environment, they need a place to conduct their business and need things

to eat. And this was this was their jungle. Yes, another really interesting point brought to my attention by the same CBC piece, Uh that I've never read about this before, But this is about the role of prehistoric fungus in shaping the evolution and eventual trophic dominance of the mammals that became our direct ancestors. Without fungus, we almost certainly wouldn't exist in multiple ways. And here's another one of those ways. All right, So I think about the Katie

extinction event. We've discussed it many times on the show. Uh, it's the the event that killed the dinosaurs, the non avian dinosaurs, the dinosaurs that did not become modern day words died in this event. About sixty five to sixty six million years ago, there was a great and sudden dying of many life forms, maybe something like sevent of all life on Earth when extinct. I think about eight

percent of animal species disappeared. Many scientists think this was probably mostly due to an enormous impact from space, So there's still some disagreement about the relative role of other things like volcanic eruptions and other factors. But the impact hypothesis, which is the most common, most important factor that's attributed these days. It states that a giant comet or asteroid at orbital speed struck the Earth in an area that is now the cheek Shulu Crater in the Yucatan Peninsula.

And this impact, of course, it kicked up stuff. It kicked up an unbelievable amount of dust and particulate matter, which clouded the atmosphere and blocked sunlight, possibly for months at a time, which would kill off a huge amount of Earth's plant life, which of course needs sunlight to survive.

You cut off the sunlight, the plants die, right. This is, of course the same concept that is employed in the concept of nuclear winter, in which a nuclear war would send up enough material the smoke of of fire storms, burning cities, burning forests, uh, sending all that stuff up into the atmosphere and creating a kind of sarcophagus on the Earth, preventing as much sunlight from reaching the Earth

yes surface, yeah, yeah, similar concepts so uh. Of course, the most direct problem with this is it would disrupt the food chain at its source. Right. The food chain is typically based on photosynthetic organisms that make their bodies by using sunlight. They die without the sunlight, and then with them dead, what can all the animals and other things eat. So so it's going to kill things all

throughout the food chain through resource deficiency. But there's enough other thing here that is worth considering, which is the role of fungus. So a blotted sky would lead to an Earth just covered in dead, decaying plant matter. Uh. And again the sky is dark, so this is almost a perfect condition for fungi to thrive. Think of Earth after the Katie impact as mold world. It's mold planet. Maybe not literally mold, but you know, the probably mold.

I don't know, I didn't look into it. It's fungus um. So it would be boom time for fungus, and it would represent a threat to surviving animals which could succumb to fungal infections in a world where fungus is all over the place and thriving, and suddenly, in this context, in a world where for hundreds of millions of years, the dominant animals have been reptile formed, our tiny mammalian ancestors would quite suddenly have a powerful survival advantage over reptiles.

Being warm blooded. In fact, it seems that one of the pressures driving the evolution of warm bloodedness is the threat of infection by fungus. Like your warm body, your dog's warm body, the warm bodies of the rats under the floorboards are in part machines for fighting parasitic infections by fungus. To quote Arturo Casadival, a professor of public health at Johns Hopkins University, uh quote, the reptiles are

quite susceptible to fungal diseases. But your typical mammal, which maintains a temperature in the mid thirties or so, and I guess they'd be celsius, not fahrenheit, creates a thermal exclusionary zone for fungi. Thus, mammals, being warm blooded, gave them a foothold to become more successful and dominant across multiple ecosystems during this time of doom and rot for the cold blooded kingdom of reptiles. I think that's fascinating.

Tens of millions of years before the discovery of penicillin killer, fungus was all already offering us a leg up by having shaped our evolution in such a way that we resist. You know, our ancestors resisted it, and the reptiles could not as easily resisted, thus making helping mammals become more dominant. And just one more thing on this subject of general

prehistoric fungus. So there was a twenty nineteen study I was looking at the chase land based fungus development even farther back into prehistory, so we would already uh, we had already seen evidence that the first living organisms to UH to colonize, to fully colonize the land where probably

these little fungal organisms. There was a paper published in Nature in twenty nineteen by Lauren at All called early Fungi from the Proterozoic era in Arctic Canada, and there was an excellent article about this research in the New York Times by former Stuff to Blow your Mind guest Carl Zimmer, I recommend checking that out. It's called a billion year old fungus may hold clues to life survival

on land. But the short version is that in twenty nineteen, the group of researchers they published findings of fossil remains of an ancient fungus which they named Rasafirah Giraldi. And this fungus is apparently about a billion years old, roughly like six hundred million years older than the previous last common ancestor of all fungus had been thought to emerge.

And if this is correct, it would definitely mean that fungi were colonizing land on their own before plants, before anything else that we know of lived on land except maybe some bacteria. Uh. If so, what were they eating? Possibly bacteria, we don't know for sure. So basically zimmer saying that we are stardust, we are golden, we are

billion year old fungi. I don't think there's a suggestion that the fungus is an ancestor of ours, but it is it suggested that this fungus probably played an important role in shaping the ecosystems that allowed our direct ancestors to survive. So we are not of Zugdamoin, but we are at least unwitting u. We're in the dead of Subtomo. Yeah, alright, on that note, we're gonna take one more break, but when we come back, we will return, specifically to interpretations

of prototax It s thank alright, We're back. Alright. So we were discussing the proposal that the prototaxites fossils were actually gigantic stalks of fungus. Uh. Not a rotting conifer tree with fungus in it, not a giant alga, but just a huge piece of fungus, a tree sized piece of fungus. What is the evidence for this, Well, there was some There's been more and more evidence supporting the

fungal hypothesis in the recent decades. Uh. To read a quote from an article I was reading about this in New Scientists from see Kevin Boyce, a geophysicist to the University of Chicago. Quote. No matter what argument you put forth, people say it's crazy. A six meter fungus doesn't make any sense. But here's the fossil. Uh. And so why does boys? Why is boys so confident that it is

a fungus? Well Voice was involved in research that attempted to look for clues to the classification of prototaxides fossils by analyzing different levels of trace carbon compounds within them. I thought this was really interesting. Now, note that this is not carbon dating. These fossils are far too old to be subject to accurate carbon dating methods, and they're

not They're not trying to establish dates for them. But it does follow some similar principles to what's done in radiocarbon dating, which is looking at different isotopes of the element carbon within the object, and in so in carbon dating, these isotopes I think are usually carbon twelve and carbon fourteen. In the research on prototaxides it was carbon twelve and carbon thirteen, and basically the reasoning went like this, Plants get essentially all of their carbon content from the two

in the air. Again one of my favorite facts about nature. It's so counterintuitive. Plants make their bodies out of C O two that they absorbed from the atmosphere using energy acquired from sunlight to do the chemical work. But the atoms that make up the carbon content of plants, that's from the air. When you think about it, next time you burn charcoal, you're burning carbon that was once the body of a plant that was made out of gas from the air. I don't think I'll ever get over them.

I mean, it always seems like the natural thing to assume is that the matter that makes up a plant comes up out of the ground. Uh. And I think, you know, some small content like minerals and trace elements and stuff like that might be absorbed through the water, of course, absorbed through the roots. But yeah, the carbon content comes from the C O two in the air. Yeah. Uh. And so for this reason, of course, because plants make their make their you know, the carbon in their bodies

out of the air. The ratios of different carbon isotopes found in plants or fairly predictable for plants that were

alive at the same time. It's based on the ratios of carbon isotopes found in the atmosphere, But the ratios of carbon twelve and carbon thirteen found in fungus are not always so predictable, since, like us, they get the carbon content of their bodies from food rather than from the air, and that food could potentially include a number of sources producing wacky isotope ratios between carbon twelve and carbon thirteen, And what the researchers found was that in fact,

the carbon twelve to carbon thirteen levels in these prototaxites fossils were not consistent, suggesting that they are that they were not plants, that the carbon in them was coming from somewhere other than the air, and thus that they were less likely to be plants more likely to be something that was making their bodies out of food that

they ate, which would include fungus. Another quote from Voice in that New Scientist article quote, a six M fungus would be odd enough in the modern in the world, but at least where used to trees quite a bit bigger plants at that time, where a few feet tall. Invertebrate animals were small, and there were no terrestrial vertebrates, this fossil would have been all the more striking in such a diminutive landscape, again, standing up above anything else

that would have been around. Yeah, it just would have yet dwarfed everything else. So based on what I've read, I think I'm fairly convinced by the fungal hypothesis that this was a giant six meter twenty foot tall piece of fungus. Yeah, and I like the idea that is often presented to that it it would have need it would have needed to to grow that high so as to help spread the spores, like you have a tangible

reason for achieving that height. I don't know, is there a reason in the in the algae theory about why a giant alga would need to be that tall? Is it not that it's not tall, that they were supposed to be horizontal or something. Um, you do see the horizontal aspect of that brought up at times, So that's that's certainly seems to be a possibility. But we'll get into another horizontal theory here in a minute. Um. Now, you know, as we mentioned earlier, that algo hypothesis has

never completely gone away. In one of the more interesting angles on it is that um prototax i t S might have been a composite organism arising from algae living among fungal filaments. This is of course nothing completely alien because we have these today, we have lichen so and this would have been essentially a parasitic or symbiotic relationship between the the alergaye and the fungus but it would

have essentially been a giant lichen. Then now another tantalizing theory relates to liver warts, which we mentioned are already is being a you know, primitive form of of plant life, kind of kind of like like moss prototerrestrial plants. Yeah, and so it's been suggested that instead of these things being um vertical pillars, instead of being this phallic landscape um that is that is so hauntingly depicted in some of these instances of paleo art detailing prototax it s,

what have instead? Uh, yeah, they were just rolled up carpets of liver warts. Now let me read a description here. This was from a This was discussed in a two thousand ten American Journal of Botany paper by Graham at All, And I'm gonna read just a quote from it here. Quote. Our comparative analyzes in instead indicated that prototax it is formed from partially degraded wind gravity or water rolled mats of mixo tropic liver warts having fungal and santo bacterial associates,

much like the modern liver wart genius Um marchantia. We proposed that the fossil body is largely derived from abundant, highly degradation resistant tubular right zoids of marcantioid liver warts intermixed with tubular microbial elements. So I know that's that sounds like a bit much, but basically the idea here is um imagine, AstroTurf has been laid out across the Devonian landscape, and then the wind starts, a blowing wind or gravity or water, right, all three of these things

begins to roll the AstroTurf back up like wrestling maps. Yeah, like wrestling mats, rolling them up into these big tubes. Then uh, these big rolls of AstroTurf, and those big rolls of AstroTurf just set there and then eventually, you know, fossilized. Like basically, that's the idea, except instead of it being AstroTurf, it is the liver warts that have grown across the surface of the planet. Now, yeah, this is okay. I won't deny it just because it's less exciting than the

giant alerts the fungus. In a sense, it's less exciting. Yes, yeah, it's certainly less exciting, but I would argue that it is equally weird. It is. It is also just like a weird idea of the landscape, like a landscape that looks like they're just a bunch of rolled up old carpets made out of green slime. That's that's strange. Uh. And apparently this is not you know, apparently some commentators

have some issues with this particular theory. It's not I don't think it's widely accepted, but it is still such a strange idea. I can't help but but find it, you know, weirdly amusing. There was actually amused by it. There was actually a bit of art with this study. It's worth looking up if you can find it. And

it's yeah, it's just bizarre. It's like this bright green landscape and then they're all these just rolls of moss carpet out there, just laying around like somebody left them, as if the god this came to install vegetation on the earth and simply got bored or went off for

a smoke break and just left everything half finished. Uh. Now, one last question I thought we should look at is obviously, you know, there are no tree sized columns of fungus or whatever they were today, So something happened to the prototaxids to drive them extinct. Any idea what that might be, I think we don't know for sure, but Huber has suggested something the same researcher you were pointing to earlier. Huber has suggested that actually the prototaxity suffered parasitic infestations

from recently evolved insects. Remember this, this would be also a time when the land is being colonized by various forms of invertebrates, and these land dwelling arthropods would dig little holes into the stalks of prototaxids. You can apparently see evidence of these probable insect bore holes in the fossil remains of prototaxids today, and these might have played

some role in driving the giant fungus extinct. Again, it comes back to the idea that the fungal world essentially, you know, drives out into the wilderness and remakes it into something that's habitable. But then come the new inhabitants, and then come the inheritors of the earth, and the inheritors generally do not treat those that came before them. So well. So true, but of course the fungus never really goes away, right, It just kind of goes underground

and it is true. I think we do have to remind us, like we can get so obsessed with species that we we forget sort of like the broader view of life itself, you know. So, yes, it's not like it's not like the day the fungus died. It's not like the day that the fungal legions lost. No, they continued and continue to thrive on the planet. But they thrive where they where there is a niche for them to occupy. They fit right in there. Sometimes there's a shroom,

sometimes there's a shroom. He's this shroom for his particular time and place. Absolutely, so there you have it. Prototax i t s. Obviously, this is a topic where you know, hopefully there'll be more studies in the future that will shed more light on this fossil mystery. Uh, this mystery fossil. But but hopefully we we were we did a good job here about just you know, introducing you to its world, to its strange world. We are not done with prehistoric fungus.

I'm sure there will be more to come back to in the future. Yes, praise zug Moy, we probably will. Speaking of zug Moy, the the demon queen of fungus from Dungeons and Dragons in the under Dark. In Dungeons and Dragons, they have a particular um like tree sized mushroom that everybody like makes at least the would substitute for the underdark called zirkle would. So I can't help. But since um an affinity here between zirkle would and uh pro otex it t s uh, it seems it

seemed like basically the same concept. Well, let's hope insects don't don't start boring holes in the under dark. Yeah. Also, I'm not completely sure you would be able to build a log cabin out of prototax it t s. But but Hubert does mention a particular species of large mushroom that that was traditionally carved into some sort of shape

by native peoples of North America. I believe. Huh. You know, one thing, one question I didn't find the answer to yet maybe it's out there, is how hard would this thing have been? Yeah? I mean could you, yeah, like, could you carve it into boards and make lumber out of it? Or would it have been relatively soft and easy to knock over with a good shove. Yeah, I mean, I guess Luckily there there there aren't gonna be any large animals that are gonna come and push you over.

It's gonna it's gonna come down to kind of like we're talking with the Roles, It's going to be going to come down to wind and water and gravity, and and these things are inevitably going to fall over. They did fall over. That's the that's how they're preserved as fossils, horizontally and not vertically. Um, in the same way that that our tallest and most impressive trees today will inevitably

at some point fall over and become horizontal. Um. But but yeah, I think it comes back to what you said to about like this being kind of the sticking point sometimes for people with the vertical fungal interpretation. People just say, well, how could that be? How could these things have existed, how could they have stood? How could they have grown like this? Uh? And again it just comes back to the intriguing nature of it as well. It would it was just such an alien world and

this was the largest alien on the landscape. Does it for me? All right? Uh? In the meantime, if you want to check out other episodes of stuff to blow your mind, you know where they are there over stuff to Blow your Mind dot com. They're also wherever you get your podcasts. There are a million places to get

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