December 17, 2019 • 54 mins
Did 20-foot-tall giant fungi rule the earth 400 million years ago? In this episode of Stuff to Blow Your Mind, Robert and Joe discuss the puzzling prototaxites fossils from the Devonian period.
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Speaker 1 (00:01):
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 mourning
was upon. The world whirled in its greening, the spring
time of the Earth. The environment was arid and warm,
(00:23):
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. For what
I at first took for primitive conifers proved anything. But
(00:46):
each of these cylindrical giants stood some twenty feet high
and were a good yard wide. They towered above the
Devonian world like stylight pillars, and I observed just a
hint of spores carried away from their czaar. I wondered, then,
might these organisms to be giant mushrooms? But that's when
(01:06):
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.
(01:26):
Welcome to Stuff to Blow Your Mind, a production of
I Heart Radios How Stuff Works. 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,
(01:48):
well worth seeking out even in today's 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,
(02:11):
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 imagining what it might be like to
walk amid this strange, these strange h specimens, this all
(02:34):
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.
(02:58):
I think there's actually a lot of interesting stuff we 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 were the tallest standing
things of their time, and we don't know for sure
what they were. We have we have better ideas than
(03:18):
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 period 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
(03:41):
look up the images of prototyps I 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.
(04:04):
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 and resulting illustrations
(04:25):
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
(04:49):
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 tantalized fossil then 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
(05:12):
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
(05:34):
Devon area in England where some of these UH fossil
finds come from. So Logan found UH these specimens in
the exposed sections of Devonian rock on the shores of
the I believe it's gossip a Bay in Quebec, in
particularly an area that is called seal Cove, which he
was mapping for coal and other minerals. Well, this fits
(05:56):
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 in the Canadian Rockies were originally
found because railroad workers who were building railroads through the area.
(06:20):
We're finding the stone bugs everywhere, and that eventually attracted
the attention of paleontologists to come and investigate. 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 the early history of this fossil find uh
(06:41):
comes to us from paleo biologist Francis Huber of the
National Museum of Natural History and Washington, d C. Who
wrote a two thousand and one piece titled Rotted Wood
Alga 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,
(07:05):
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 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
(07:28):
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
it can come become quite a dramatic issue as well.
Unravel 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
(07:51):
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, it became
clear that the fossilized tissue was uh solicified, you know,
containing an entangled mesh that resembled fungal my cilia. He
(08:12):
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 this fossil. He traveled to seal
Cove himself and obtained additional samples. Okay, so they've found
this giant fossilized trunk of something. It looks like it
(08:32):
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 now now my cilium is the
vegetative part of a fungus. Just reminded everybody. It's a
It's a mass of branching vein like hi fe that
(08:53):
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 uh,
(09:13):
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 decomposer fungus within the
decomposing uh specimen, all of this preserved in a single
fossil specimen. Well, that would make sense. It's it is
(09:35):
a tree trunk, it's infested with fungal Mysilia type structures, right,
And so he gave it the name proto tax 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 a
(09:56):
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
(10:17):
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 proto tax 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, I mean that's creepy. Well. Yeah.
(10:40):
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 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 fight.
(11:00):
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
(11:22):
scathing and slanderous. Uh in terms of criticizing 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. Caruthers, but
but just based on Huber's writing, one is tempted debut
Caruthers is something of a bully in his field while
(11:43):
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 or another so um. According to Hubert, Dawson fought
for his initial classification, but but then later he ends
(12:05):
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 proto taxi t s uh. So. I
imagine that at least of the time that Huber was
(12:27):
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 basil Osaurus. Okay, uh,
(12:49):
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.
(13:14):
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
(13:35):
nineteen when one A. H. 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 to Huber. Basically,
this guy was ignored and the alta interpretation continued with
(13:59):
papers and you know it's it's reacent. It's say nineteen
seventy nine and ninety 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,
(14:21):
I've seen estimates of a maximum known height of six
or even eight meters, like twenty to twenty five ft.
So you've got a giant six m high stalk 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
(14:42):
like that. Yeah, it's it's kind of like it's like
a tree. It's not a tree, h It's 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's to it, above it.
(15:03):
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? Might 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
(15:24):
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,
(15:47):
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
(16:09):
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
(16:33):
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 prototaxites is. But before that, let's take a break
and then we come back. We can delve into mushroom theory.
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Thank alright, we're back. So we've been talking about these
(19:10):
fossil organisms from hundreds of millions of years ago, known
as prototax id s, 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.
(19:32):
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
algy past, for prototax it t s the most popular
hypothesis at the moment. Uh seems to be the fungus hypothesis. Uh.
(19:52):
Not to say they are not criticisms or questions regarding
the fungus hypothesis, but it does seem to be the
most popular interpretation. Amazing 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 Shitaki's shape, right, yeah,
(20:15):
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 ferry sitting on top of it. Right.
(20:37):
But but basically the fungus interpretation 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, a likin, or perhaps
even an algae. Uh. You know, some of this points
in that direction here as well. But on this issue
(21:00):
I want to turn back to Huber again because this
is what he has to say about the algae interpretation
and ultimately, uh, the the move towards the fungal interpretation quote.
In my opinion, prototaxids does not have the structural anatomy
nor morphology of an alga chemo Taxonomic analysis by Nicholas
(21:23):
concluded that the chemical constituents found in prototax it certain
fatty acids cuton and subarin differed from modern Alga, 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
(21:44):
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 algial
affinity was still possible. The anatomy morphology and a currences
cannot be refuted so easily. He also points to UH
(22:05):
nine six transmission electron microscope findings from Rudolph Schmidt uh And.
This was a paper titled Septal Pores and prototax it
t s an enigmatic Devonian plant. Uh In this he
reveals that sceptal pores are are found here, suggesting fungal affinity.
(22:26):
Septal pores are specialized dividing walls between cells, septa found
in almost all species of fung guy in the phylum
Bassidi of my Cota. He points out that the inherent
size of prototax it tes has long been a barrier
to some when it comes to accepting fungal affinity, and
he counters this by pointing out that we have various
(22:47):
examples of of of quite large contemporary fungi uh and
extensive my Silian networks. He poses that perhaps prototaxites itself
had a vast underground Mysilian at work as well, but
we just don't have fossil evidence of that Mysilia network.
But the possible picture here is is fascinating an underground
(23:10):
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
(23:33):
fans I think I could really get behind. This is like,
this is a pulse stainments dream 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 it,
maybe it seems like a stupid question, but you know,
I stand by that like, why why is it that
(23:53):
we live in this evolutionary context land based ecosystems rather
than under the water, where we are 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
(24:14):
strange armies of scuttling, undulating, bilaterally symmetrical animals, billions of
trialo bites. You've got, you know, these extinct bottom dwelling
animals shaped kind of like death metal roly Pulley's many
legged proto arthropods with hardened plates of armor on their backs.
But also all these other organisms like the low blegged
(24:35):
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
(24:58):
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 Ediacrian period,
there you don't find any of this stuff. You find,
you know, maybe little indications of soft bodied worms, but like,
(25:19):
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
(25:42):
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,
(26:03):
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.
(26:24):
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 Mars, you know,
like what could live there? What could live there at
the time is probably limited to the kinds of things
(26:46):
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
(27:10):
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
(27:33):
some development since then, but this was back in UH.
This was a now extinct fungal organism called Torto tubas.
And that was immediately thinking, I want a T shirt
for my neighbor Torto tubas. Uh. But this is based
on research published in twenty sixteen and the Botanical Journal
of the Lenaean Society, based on physical evidence including samples
(27:56):
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
(28:18):
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 plants come from? Perhaps
(28:42):
it came from early land colonizing fungus like torto tubus.
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 to to tubas would have paved the
way for larger, more complex green plants to quite literally
(29:05):
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, right uh And then also
(29:30):
featured in the same article as Smith says quote, by
the time toward a tubas wind extinct, the first trees
and forests had come into existence. This humble subterranean 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
(29:52):
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 tubas 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
(30:17):
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 that, the competition for life and of course
all that death that'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.
(30:37):
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
to have a fruiting body like a like a mushroom
cap that we know of at the time this article
(30:59):
is published, the 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 tord the tubis. 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
(31:22):
some nutrients. And that's also pretty amazing. Right. 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
(31:44):
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. And plants and fungi also form you know,
complex symbiotic relationships with one another. They in different ways,
(32:07):
benefit from each other's presence. I was reading a piece
about a it was based on the 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
(32:29):
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 continents. Yeah,
like these these essentially become the small scale forests in
which the Devonian animals would live things that were essentially
(32:50):
like like millipedes and centipedes and uh, you know, early
things like mites and so forth, like, you know, very
small scale life. But they need an environment, they need
a place to conduct their business. They 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'd never read about this before. But this
(33:13):
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.
Al Right, So think about the Katie extinction event. We've
discussed it many times on the show. Uh. It's the
(33:34):
the event that killed the dinosaurs, the non avian dinosaurs,
the dinosaurs that did not become modern day birds 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 seventy of all life
on Earth when extinct. I think about eighty percent of
animal species disappeared. Many scientists think this was probably mostly
(33:58):
due to and a nor mist 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
(34:19):
is now the cheek Shulub 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.
(34:41):
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 you know, the smoke of of
fire storms, burning cities, burning forests, uh, sending all that
(35:01):
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
(35:26):
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 another thing here that is worth considering, which is
the role of fungus. So a blotted sky would lead
(35:48):
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 after
the Katie impact as mold world. It's mold planet. Maybe
not literally mold, but you know, the probably mold. I
(36:08):
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
(36:32):
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
(36:53):
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
(37:16):
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. And I think that's fascinating.
Tens of millions of years before the discovery of penicillin killer,
(37:38):
fungus was 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 that
(37:59):
was again that 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
(38:21):
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,
this group of researchers they published findings of fossil remains
(38:44):
of an ancient fungus which they named Orasafirah 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 him
or And if this is correct, it would definitely mean
that fungi were colonizing land on their own before plants,
(39:07):
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's
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
(39:28):
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 zugdomoy, but we
are at least unwitting of sutomot. Yeah. Alright, on that note,
we're going to take one more break, but when we
(39:48):
come back, we will return, specifically to interpretations of prototax
It sank alright, We're back, alright. So we were discussed saying, uh,
the proposal that the Prototaxites fossils were actually gigantic stalks
of fungus. Uh. Not a rotting conifer tree with fungus
(40:10):
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. Uh. To read a quote from
an article I was reading about this in New Scientists
from see Kevin Boyce, a geophysicist at the University of
(40:34):
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 prototaxites fossils by analyzing different
(40:56):
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
(41:17):
looking at different isotopes of the element carbon within the object,
and so in carbon dating, these isotopes I think are
usually carbon twelve and carbon fourteen. In the research on prototaxids,
it was carbon twelve and carbon thirteen, and basically the
reasoning went like this, Plants get essentially all of their
(41:38):
carbon content from the CEO 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 absorb 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.
(42:00):
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
(42:21):
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 are fairly predictable for plants that were
alive at the same time. It's based on the ratios
(42:44):
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
(43:08):
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
(43:28):
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 meter fungus
would be odd enough in the modern world, but at
least where used to tree is 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
(43:50):
would have been all the more striking in such a
dominion of landscape, again, standing up above anything else that
would have been around it. It just would have 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,
(44:11):
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. 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
(44:32):
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 algae hypothesis has
never completely gone away. In one of the more interesting
(44:55):
angles on it is that um prototax i t s
might have been a comple positive 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 algae and the fungus. But it
(45:18):
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
(45:42):
being um, vertical pillars, instead of being this phallic landscape
um that is uh that is so hauntingly depicted in
some of these instances of paleo art detailing prototax it
t s would 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
(46:05):
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
indicate that prototaxidy's formed from partially degraded wind, gravity, or
water rolled mats of mixo tropic liver wards having fungal
(46:25):
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 rhizoids of
marcantioid liver wards intermixed with tubular microbial elements. So, uh,
(46:48):
I know that's that sounds like a bit much, But
basically the idea here is um imagine AstroTurf has been
laid out um across the Devonian landscape. Then the wind
starts a blowing wind or gravity or water, right, all
three of these things begins to roll the the AstroTurf
(47:09):
back up like wrestling maps. Yeah, like wrestling. Pat's 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
(47:32):
of the planet. Now, yeah, this is okay. I won't
deny it just because it's less exciting than the giant
pillars of 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 also just like a weird
idea of the landscape, but like a landscape that looks
(47:53):
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 uh 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,
(48:18):
you know, weirdly amusing. There was actually aged to be
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 gods came to install
(48:40):
vegetation on the earth and simply got bored or went
off for a smoke break and just left everything half finished. 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 prototaxids
(49:01):
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 would be also a
(49:21):
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
(49:45):
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 only
do not treat those that came before them. So well,
so true, but of course the fungus never really goes away, right,
(50:07):
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,
(50:28):
they continued and continue to thrive on the planet. But
they they thrive where they where, 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
(50:49):
you have it. Prototax I t s. Obviously this is
a topic where, you know, hopefully they'll be more studies
in the future that will shed more light on this
fossil mystery. Uh, this mystery fossil. But uh, 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
(51:11):
sure there will be more to come back to in
the future. Yes, praise Zugmoy, we probably will. Speaking of
zug Mooy, 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 it would substitute for the under dark, called
(51:32):
zirkle would. So I can't help. But since um an
affinity here between zirkle would and uh prototax it s uh,
it seems it seems 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
(51:52):
it t s. But but Hubert does mention a particular
species of of large mushroom that that was traditionally carved
into some sort of shape by native peoples of North America.
I believe. Huh uh. 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
(52:14):
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 uh 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
(52:36):
are inevitably going to fall over. They did fall over.
That's the That's how they are preserved as fossils horizontally
and not vertically um in the same way that that
are 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 he said to
(52:58):
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. That does her for me,
(53:22):
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 at stuff to
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(53:44):
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the future, just to say hello. You can email us
at contact. That's Stuff to blow ow your Mind dot com.
(54:08):
Stuff to Blow Your Mind is a production of iHeart
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visit the iHeart Radio app, Apple Podcasts, or wherever you
listen to your favorite shows.
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 mourning
was upon. The world whirled in its greening, the spring
time of the Earth. The environment was arid and warm,
(00:23):
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. For what
I at first took for primitive conifers proved anything. But
(00:46):
each of these cylindrical giants stood some twenty feet high
and were a good yard wide. They towered above the
Devonian world like stylight pillars, and I observed just a
hint of spores carried away from their czaar. I wondered, then,
might these organisms to be giant mushrooms? But that's when
(01:06):
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.
(01:26):
Welcome to Stuff to Blow Your Mind, a production of
I Heart Radios How Stuff Works. 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,
(01:48):
well worth seeking out even in today's 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,
(02:11):
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 imagining what it might be like to
walk amid this strange, these strange h specimens, this all
(02:34):
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.
(02:58):
I think there's actually a lot of interesting stuff we 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 were the tallest standing
things of their time, and we don't know for sure
what they were. We have we have better ideas than
(03:18):
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 period 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
(03:41):
look up the images of prototyps I 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.
(04:04):
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 and resulting illustrations
(04:25):
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
(04:49):
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 tantalized fossil then 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
(05:12):
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
(05:34):
Devon area in England where some of these UH fossil
finds come from. So Logan found UH these specimens in
the exposed sections of Devonian rock on the shores of
the I believe it's gossip a Bay in Quebec, in
particularly an area that is called seal Cove, which he
was mapping for coal and other minerals. Well, this fits
(05:56):
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 in the Canadian Rockies were originally
found because railroad workers who were building railroads through the area.
(06:20):
We're finding the stone bugs everywhere, and that eventually attracted
the attention of paleontologists to come and investigate. 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 the early history of this fossil find uh
(06:41):
comes to us from paleo biologist Francis Huber of the
National Museum of Natural History and Washington, d C. Who
wrote a two thousand and one piece titled Rotted Wood
Alga 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,
(07:05):
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 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
(07:28):
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
it can come become quite a dramatic issue as well.
Unravel 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
(07:51):
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, it became
clear that the fossilized tissue was uh solicified, you know,
containing an entangled mesh that resembled fungal my cilia. He
(08:12):
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 this fossil. He traveled to seal
Cove himself and obtained additional samples. Okay, so they've found
this giant fossilized trunk of something. It looks like it
(08:32):
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 now now my cilium is the
vegetative part of a fungus. Just reminded everybody. It's a
It's a mass of branching vein like hi fe that
(08:53):
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 uh,
(09:13):
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 decomposer fungus within the
decomposing uh specimen, all of this preserved in a single
fossil specimen. Well, that would make sense. It's it is
(09:35):
a tree trunk, it's infested with fungal Mysilia type structures, right,
And so he gave it the name proto tax 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 a
(09:56):
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
(10:17):
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 proto tax 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, I mean that's creepy. Well. Yeah.
(10:40):
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 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 fight.
(11:00):
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
(11:22):
scathing and slanderous. Uh in terms of criticizing 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. Caruthers, but
but just based on Huber's writing, one is tempted debut
Caruthers is something of a bully in his field while
(11:43):
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 or another so um. According to Hubert, Dawson fought
for his initial classification, but but then later he ends
(12:05):
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 proto taxi t s uh. So. I
imagine that at least of the time that Huber was
(12:27):
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 basil Osaurus. Okay, uh,
(12:49):
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.
(13:14):
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
(13:35):
nineteen when one A. H. 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 to Huber. Basically,
this guy was ignored and the alta interpretation continued with
(13:59):
papers and you know it's it's reacent. It's say nineteen
seventy nine and ninety 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,
(14:21):
I've seen estimates of a maximum known height of six
or even eight meters, like twenty to twenty five ft.
So you've got a giant six m high stalk 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
(14:42):
like that. Yeah, it's it's kind of like it's like
a tree. It's not a tree, h It's 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's to it, above it.
(15:03):
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? Might 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
(15:24):
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,
(15:47):
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
(16:09):
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
(16:33):
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 prototaxites is. But before that, let's take a break
and then we come back. We can delve into mushroom theory.
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Thank alright, we're back. So we've been talking about these
(19:10):
fossil organisms from hundreds of millions of years ago, known
as prototax id s, 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.
(19:32):
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
algy past, for prototax it t s the most popular
hypothesis at the moment. Uh seems to be the fungus hypothesis. Uh.
(19:52):
Not to say they are not criticisms or questions regarding
the fungus hypothesis, but it does seem to be the
most popular interpretation. Amazing 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 Shitaki's shape, right, yeah,
(20:15):
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 ferry sitting on top of it. Right.
(20:37):
But but basically the fungus interpretation 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, a likin, or perhaps
even an algae. Uh. You know, some of this points
in that direction here as well. But on this issue
(21:00):
I want to turn back to Huber again because this
is what he has to say about the algae interpretation
and ultimately, uh, the the move towards the fungal interpretation quote.
In my opinion, prototaxids does not have the structural anatomy
nor morphology of an alga chemo Taxonomic analysis by Nicholas
(21:23):
concluded that the chemical constituents found in prototax it certain
fatty acids cuton and subarin differed from modern Alga, 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
(21:44):
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 algial
affinity was still possible. The anatomy morphology and a currences
cannot be refuted so easily. He also points to UH
(22:05):
nine six transmission electron microscope findings from Rudolph Schmidt uh And.
This was a paper titled Septal Pores and prototax it
t s an enigmatic Devonian plant. Uh In this he
reveals that sceptal pores are are found here, suggesting fungal affinity.
(22:26):
Septal pores are specialized dividing walls between cells, septa found
in almost all species of fung guy in the phylum
Bassidi of my Cota. He points out that the inherent
size of prototax it tes has long been a barrier
to some when it comes to accepting fungal affinity, and
he counters this by pointing out that we have various
(22:47):
examples of of of quite large contemporary fungi uh and
extensive my Silian networks. He poses that perhaps prototaxites itself
had a vast underground Mysilian at work as well, but
we just don't have fossil evidence of that Mysilia network.
But the possible picture here is is fascinating an underground
(23:10):
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
(23:33):
fans I think I could really get behind. This is like,
this is a pulse stainments dream 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 it,
maybe it seems like a stupid question, but you know,
I stand by that like, why why is it that
(23:53):
we live in this evolutionary context land based ecosystems rather
than under the water, where we are 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
(24:14):
strange armies of scuttling, undulating, bilaterally symmetrical animals, billions of
trialo bites. You've got, you know, these extinct bottom dwelling
animals shaped kind of like death metal roly Pulley's many
legged proto arthropods with hardened plates of armor on their backs.
But also all these other organisms like the low blegged
(24:35):
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
(24:58):
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 Ediacrian period,
there you don't find any of this stuff. You find,
you know, maybe little indications of soft bodied worms, but like,
(25:19):
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
(25:42):
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,
(26:03):
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.
(26:24):
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 Mars, you know,
like what could live there? What could live there at
the time is probably limited to the kinds of things
(26:46):
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
(27:10):
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
(27:33):
some development since then, but this was back in UH.
This was a now extinct fungal organism called Torto tubas.
And that was immediately thinking, I want a T shirt
for my neighbor Torto tubas. Uh. But this is based
on research published in twenty sixteen and the Botanical Journal
of the Lenaean Society, based on physical evidence including samples
(27:56):
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
(28:18):
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 plants come from? Perhaps
(28:42):
it came from early land colonizing fungus like torto tubus.
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 to to tubas would have paved the
way for larger, more complex green plants to quite literally
(29:05):
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, right uh And then also
(29:30):
featured in the same article as Smith says quote, by
the time toward a tubas wind extinct, the first trees
and forests had come into existence. This humble subterranean 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
(29:52):
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 tubas 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
(30:17):
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 that, the competition for life and of course
all that death that'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.
(30:37):
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
to have a fruiting body like a like a mushroom
cap that we know of at the time this article
(30:59):
is published, the 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 tord the tubis. 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
(31:22):
some nutrients. And that's also pretty amazing. Right. 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
(31:44):
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. And plants and fungi also form you know,
complex symbiotic relationships with one another. They in different ways,
(32:07):
benefit from each other's presence. I was reading a piece
about a it was based on the 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
(32:29):
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 continents. Yeah,
like these these essentially become the small scale forests in
which the Devonian animals would live things that were essentially
(32:50):
like like millipedes and centipedes and uh, you know, early
things like mites and so forth, like, you know, very
small scale life. But they need an environment, they need
a place to conduct their business. They 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'd never read about this before. But this
(33:13):
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.
Al Right, So think about the Katie extinction event. We've
discussed it many times on the show. Uh. It's the
(33:34):
the event that killed the dinosaurs, the non avian dinosaurs,
the dinosaurs that did not become modern day birds 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 seventy of all life
on Earth when extinct. I think about eighty percent of
animal species disappeared. Many scientists think this was probably mostly
(33:58):
due to and a nor mist 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
(34:19):
is now the cheek Shulub 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.
(34:41):
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 you know, the smoke of of
fire storms, burning cities, burning forests, uh, sending all that
(35:01):
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
(35:26):
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 another thing here that is worth considering, which is
the role of fungus. So a blotted sky would lead
(35:48):
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 after
the Katie impact as mold world. It's mold planet. Maybe
not literally mold, but you know, the probably mold. I
(36:08):
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
(36:32):
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
(36:53):
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
(37:16):
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. And I think that's fascinating.
Tens of millions of years before the discovery of penicillin killer,
(37:38):
fungus was 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 that
(37:59):
was again that 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
(38:21):
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,
this group of researchers they published findings of fossil remains
(38:44):
of an ancient fungus which they named Orasafirah 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 him
or And if this is correct, it would definitely mean
that fungi were colonizing land on their own before plants,
(39:07):
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's
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
(39:28):
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 zugdomoy, but we
are at least unwitting of sutomot. Yeah. Alright, on that note,
we're going to take one more break, but when we
(39:48):
come back, we will return, specifically to interpretations of prototax
It sank alright, We're back, alright. So we were discussed saying, uh,
the proposal that the Prototaxites fossils were actually gigantic stalks
of fungus. Uh. Not a rotting conifer tree with fungus
(40:10):
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. Uh. To read a quote from
an article I was reading about this in New Scientists
from see Kevin Boyce, a geophysicist at the University of
(40:34):
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 prototaxites fossils by analyzing different
(40:56):
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
(41:17):
looking at different isotopes of the element carbon within the object,
and so in carbon dating, these isotopes I think are
usually carbon twelve and carbon fourteen. In the research on prototaxids,
it was carbon twelve and carbon thirteen, and basically the
reasoning went like this, Plants get essentially all of their
(41:38):
carbon content from the CEO 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 absorb 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.
(42:00):
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
(42:21):
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 are fairly predictable for plants that were
alive at the same time. It's based on the ratios
(42:44):
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
(43:08):
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
(43:28):
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 meter fungus
would be odd enough in the modern world, but at
least where used to tree is 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
(43:50):
would have been all the more striking in such a
dominion of landscape, again, standing up above anything else that
would have been around it. It just would have 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,
(44:11):
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. 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
(44:32):
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 algae hypothesis has
never completely gone away. In one of the more interesting
(44:55):
angles on it is that um prototax i t s
might have been a comple positive 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 algae and the fungus. But it
(45:18):
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
(45:42):
being um, vertical pillars, instead of being this phallic landscape
um that is uh that is so hauntingly depicted in
some of these instances of paleo art detailing prototax it
t s would 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
(46:05):
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
indicate that prototaxidy's formed from partially degraded wind, gravity, or
water rolled mats of mixo tropic liver wards having fungal
(46:25):
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 rhizoids of
marcantioid liver wards intermixed with tubular microbial elements. So, uh,
(46:48):
I know that's that sounds like a bit much, But
basically the idea here is um imagine AstroTurf has been
laid out um across the Devonian landscape. Then the wind
starts a blowing wind or gravity or water, right, all
three of these things begins to roll the the AstroTurf
(47:09):
back up like wrestling maps. Yeah, like wrestling. Pat's 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
(47:32):
of the planet. Now, yeah, this is okay. I won't
deny it just because it's less exciting than the giant
pillars of 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 also just like a weird
idea of the landscape, but like a landscape that looks
(47:53):
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 uh 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,
(48:18):
you know, weirdly amusing. There was actually aged to be
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 gods came to install
(48:40):
vegetation on the earth and simply got bored or went
off for a smoke break and just left everything half finished. 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 prototaxids
(49:01):
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 would be also a
(49:21):
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
(49:45):
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 only
do not treat those that came before them. So well,
so true, but of course the fungus never really goes away, right,
(50:07):
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,
(50:28):
they continued and continue to thrive on the planet. But
they they thrive where they where, 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
(50:49):
you have it. Prototax I t s. Obviously this is
a topic where, you know, hopefully they'll be more studies
in the future that will shed more light on this
fossil mystery. Uh, this mystery fossil. But uh, 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
(51:11):
sure there will be more to come back to in
the future. Yes, praise Zugmoy, we probably will. Speaking of
zug Mooy, 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 it would substitute for the under dark, called
(51:32):
zirkle would. So I can't help. But since um an
affinity here between zirkle would and uh prototax it s uh,
it seems it seems 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
(51:52):
it t s. But but Hubert does mention a particular
species of of large mushroom that that was traditionally carved
into some sort of shape by native peoples of North America.
I believe. Huh uh. 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
(52:14):
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 uh 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
(52:36):
are inevitably going to fall over. They did fall over.
That's the That's how they are preserved as fossils horizontally
and not vertically um in the same way that that
are 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 he said to
(52:58):
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. That does her for me,
(53:22):
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 at stuff to
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(53:44):
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