Diatoms and Diatomaceous Earth, Part 2

In this episode of Stuff to Blow Your Mind, Robert and Joe discuss the strange, fossilized microscopic algae we know as diatomaceous earth.

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Episode Transcript

Speaker 1 (00:03):
Welcome to Stuff to Blow Your Mind production of iHeartRadio.

Speaker 2 (00:12):
Hey, welcome to Stuff to Blow Your Mind. My name
is Robert.

Speaker 3 (00:15):
Lamb and I'm Joe McCormick. And today we're going to
be doing the second part in our series on the
single celled photosynthetic organisms called diatoms, and also focusing on
the silica based sedimentary material made out of the fossilized
remains of diatom shells. This material is diatomaceous Earth. If

(00:37):
you haven't heard part one, I would recommend you go
back and listen to that one before today's episode, but
for a brief refresher. In the last episode, we talked
a bit about dietom biology. Diatoms are single celled, eukaryotic
photosynthetic algae found in nearly every natural water source on
planet Earth, including not just lakes, rivers, and oceans, but

(00:59):
even more out of the way places like damp soil
and Arctic sea ice. They are not plants, they are
not animals, they're not fungi, but they do have a
cell nucleus and they make their own food using energy
from the sunlight. Diatoms are a major source of both
oxygen in Earth's atmosphere and primary organic material in the ocean,

(01:24):
So they're responsible for estimates vary, but about one fifth
of the air we breathe, and they make up a
major part of the base of the marine food web.
So if an animal is eating something in the sea,
there's a good chance that either it's a diatom, or
it's something that aid to diatom, or it's something that

(01:44):
it's something that aa die tom. So one of the
most important and unique characteristics of diatoms, the thing that
really sets them apart from other algal and planktonic organisms
in the water, is that they create a rigid, fortified
cell wall out of amorphous silica. So essentially, each diatom

(02:09):
is a little cell of algae that surrounds itself with
a porous piece of armor, a shell made out of
a material that is very similar to glass, and this
shell is called the frustule. We spent a lot of
time in the last episode just looking at and talking
about these microscopic shells because the bizarre and the diverse

(02:32):
forms these frustules take have been a source of amazement
for people ever since they were first observed under microscopes.
More than three hundred years ago, and you get kind
of different imagery depending on the first of all, in
the different species of diatom you look at, but then
also on the type of magnification and imagery you use.

(02:54):
So under light microscopes, diatoms often appear delicate and transparent,
so they're often compared to like jewels or fine glasswork,
whereas under electron microscopes they often look much stranger and
in some cases alarming, like these these shattered pieces of
alien machinery, and these frustules often accumulate in layers at

(03:18):
the bottom of bodies of water. After the diatoms dies,
the diatom's dye, the shells sink down and they turned
into a kind of diatom skeleton sludge or ooze that
over the eons can solidify into a porous, low density
kind of rock that we call diatomite. So millions of

(03:38):
years later, this sedimentary material can be dug up and
ground into a powder and sold in bulk for tons
of different household and industrial uses, including as an insecticide
like we talked about last time. Something we'll get into
a bit more this time is its use as a

(03:58):
filtration medium for liquid. It's used as an abrasive, it's
used in some toiletry products, it shows up in all
kinds of things, and so in the last episode we
were talking about just how bizarre it is that you
can go to the hardware store or the tractor supply
and buy a bag of this dust or a can
of this dust. But if you put that dust under

(04:19):
a high powered microscope, depending on how it's prepared, you
can probably still see that the grains of this mundane
stuff are filled with the broken remnants of Martian pocket
watch gears and these tiny, you know, jagged mesh tubes
and things that look like a stadium built for viruses.
And so at the end of the last episode we

(04:41):
ended up talking for a bit about one of the
most common mundane uses for diatamacious earth, which is as
a mechanical insecticide, and we got into some of the
grizzly details of how this works from the bugs perspective.

Speaker 2 (04:54):
So if you missed that episode, go back and listen
to it wherever you get your podcasts, or if you
want to watch a as well, you can get the
audio video version of that episode and this one on Netflix.

Speaker 3 (05:06):
Best way to see what our heads look like.

Speaker 4 (05:08):
Yeah, yeah, what sure are we wearing this? This is
how you do it.

Speaker 3 (05:13):
So we're going to talk more in today's episode about
human uses for these fossil alkyl skeletons. And one of
the historical human uses of dietamacious earth that I referred
to briefly in the last episode is its role in
the invention of dynamite. So I'd like to come back
and talk about that a bit more today. So if

(05:34):
you know one fact about the history of dynamite, it
is probably that it was invented by the Swedish chemist
Alfred Nobel, the same Nobel from whom we get the
Nobel Prizes. Nobel lived from eighteen thirty three to eighteen
ninety six, and for Alfred Nobel, explosives were the family business.

(05:56):
I was not aware of this beforehand, but so he
didn't just like out of no where, decide I'm going
to start making explosives. This was like a patrilineal thing.
So Alfred's father, Emmanuel Nobel, was an explosives and munitions
manufacturer who had contracts, for example, with the Tsar of Russia.
I think this would have been Zar Nicholas making things

(06:18):
like underwater mines, for the Russian military, which, yes, that
might be kind of surprising, but naval minds did exist
in the nineteenth century, primarily based at the time on gunpowder,
which was a granular mixture of potassium, nitrate, sulfur and charcoal, which,
for hundreds of years at this point, for hundreds of

(06:40):
years since its invention in ninth century China had been
the most important practical explosive known to humanity. There was
really nothing else out there that was more powerful, that
could be manufactured practically in significant quantities.

Speaker 2 (06:59):
And if you want to know a little bit more
about the Chinese history of explosives, we've recorded at least
a couple of episodes on this in the past. I
believe if he did an invention of fireworks episode at
one point, So go back, you'll find that in the
audio archives.

Speaker 3 (07:13):
Yeah. So I was reading about Nobel in a number
of sources. One of them was a twenty twenty five
history dot Com article by Christopher Klein, and just one
funny thing he noted is that the young Alfred Nobel
had actually been interested in studying poetry. Maybe he had
kind of the soul of a poet or an artist,
but his father was not a fan of this path,

(07:34):
and so tried to steer him elsewhere. He tried to
funnel his son into the explosives business like his own business.
So he sent young Alfred away at age seventeen to
study under a prominent chemist in Paris to learn about
the cutting edge of explosives in chemistry. And while pursuing

(07:54):
his education, Nobel became familiar with the work of an
Italian chemist named Ascanio Sobrero, who in eighteen forty six
had discovered a new chemical explosive called nitro glycerin.

Speaker 2 (08:10):
You know, this just really goes to show how crushed
his poetic aspirations probably were because you can't rhyme anything
with nitroglycerin or diotomaceous. I mean, maybe with great skill
you could, but you know, this alone had to just
really finish off his poetic dreams.

Speaker 3 (08:29):
Diatomacious rhymes with gracious. You know, gracious, I feel so
gracious about this diatomaceous earth that goes in my nitroglycerin. Hey,
I'm I'm maybe.

Speaker 2 (08:41):
I mean I've heard shakier rhymes before, so maybe it
could have worked.

Speaker 3 (08:47):
So to make nitroglycerin, you start with a common and
widely used sugar alcohol called glycerol or sometimes sold as glycerin.
Glycerl is a naturally occurring organic molecule, so it's produced
in the bodies of plants and animals, but you can
also make it in industrial settings. For example, it has

(09:09):
historically been one byproduct of the process of manufacturing soap,
and other industrial processes can create it. And what Sobrero
discovered is that if you do a process called nitrating glycerol.
If you nitrate glycerol by mixing it with a combination
of nitric acid and sulfuric acid, you get a massively

(09:34):
exothermic chemical reaction, so chemical reaction that puts out a
lot of heat. This mixture starts to heat up rapidly
and can become very dangerous. It can even possibly explode. However,
Sobrero figured out that if you keep cooling, if you
aggressively cool the mixture while you're stirring the constituents together,

(09:56):
you can prevent this heating and you can stabilize it.
And what you are left with is an oily liquid
explosive sometimes described as yellow in color, though I think
it's supposed to be colorless at very high purity levels.
So maybe a pale yellow color often and this mixture
that you're left with is much more energetic than gunpowder.

(10:19):
So in the mid nineteenth century, nitroglycerin would be one
of the most powerful chemical explosives that anybody had ever discovered,
and it promised to be revolutionary for tons of industries.
When we think of explosives, of course, you know, we
can think of like the dark side, like violence and warfare,
but you can also think of lots of very productive,

(10:42):
peaceful uses for dynamite, and that was a major part
of its economic value. Value in like mining, civil engineering,
and transportation basically anything that involved blasting or tunneling through rock,
those industries could be could get a huge step up
from the invention of nitroglycerin. However, it came with a
major downside. While extremely powerful, nitroglycerin was also incredibly sensitive

(11:09):
and thus incredibly dangerous.

Speaker 2 (11:12):
Yeah, for a cinematic example of this, you know, I
instantly think to the film The Wages of Fear or
the remake Sorcerer, in which you have, for plot reasons,
a truck loaded with nitroglycerin having to having to navigate
extremely bad mountain roads, and there's just a risk of

(11:32):
explosion almost you know, at every bump because of this.

Speaker 3 (11:37):
That will get more horrifying when I start talking about
some of these historical examples. But yeah, so you had
this kind of liquid fire that before it was called nitroglycerin.
Actually Ascanio Sobrero was calling it pyro glycerin. So like
the glycerin of fire, this alcohol sugar alcohol molecule of fire.
And Sobrero's journals from early synthesis do, of course, because

(12:00):
it's nineteenth century, they do include tasting notes. He says
it is sweet and pungent on the tongue and that
it smells aromatic. But he also like includes a lot
of caution in his early writing about it. He says
research must be carried out with the greatest of care.
Several of his experiments in the lab ended with unintentional explosions,

(12:22):
including one case where a drop of nitroglycerin in a
test tube exploded and embedded fragments of glass in his face.
A Sobrero would also later say that he was so
horrified by the destructive potential of nitroglycerin that he was
ashamed to have discovered it, but he also took solace
in the idea that if he had not created it,

(12:44):
somebody else would have pretty soon, you know. So it
wasn't like, you know, nobody else would have ever come
across this formula. It's just kind of it's waiting there
in physics for us to find.

Speaker 2 (12:53):
Yeah, a lot of people were working in this field
and trying to trying to find just such a substance.

Speaker 3 (13:00):
Yeah. One more note about the fact that he tasted it.
Chemists who tasted nitro in the mid nineteenth century sometimes
reported that ingesting it would create pounding headaches. I think
this is related to nitroglycerin's effect as a vasodilator, so
it relaxes blood vessels and increases blood flow and perhaps surprisingly,

(13:21):
though I would not recommend ingesting it without the you know,
without the supervision of a doctor. It is still used
today to treat like angina, pectorus, like chest pain.

Speaker 4 (13:32):
Yeah.

Speaker 2 (13:32):
Yeah, yeah, you still do hear about people who are
taking nitroglycerin.

Speaker 4 (13:37):
Yeah.

Speaker 3 (13:38):
Yeah. So, sobrero kind of leaves off with nitro for
a while, and Alfred Nobel picked up the trail. He
saw enormous potential for nitroglycerin, given the power that it
could unleash. So Nobel started experimenting to see how he
could make it practical to use. Reading about the early

(13:58):
history of nitroglycerin is this morbid mix of comedy and tragedy.
Mostly tragedy, but there is a sort of grimly ironic
element when you just read, like tail after tale of
these horribly deadly whoopsies piling up. So there are constant
stories of unintended explosions during storage and transport. If the

(14:20):
nitro got too hot might explode. The even more important
thing is if it got jostled the wrong way might explode.
It was highly sensitive to temperature, but especially shocks, physical shocks,
And though this probably isn't quite true about how it works, it,
I think sometimes it seemed to people at the time

(14:43):
that it would just explode randomly.

Speaker 2 (14:47):
Yeah, and even if not true, that's just a minor
exaggeration based on how sensitive it was.

Speaker 3 (14:54):
So there were massive explosions in Nobel's own laboratories, including
one explosion that kill Old Alfred's younger brother Emil in
eighteen sixty four. These explosions in Nobel's lab also got
his research banned from the city of Stockholm in Sweden.
They were like, okay, you can't do this here anymore.
I think Nobel had a factory in Germany that exploded,

(15:16):
killing a bunch of people. And once nitroglycerin was being
sold to the public in the eighteen sixties by Nobel
and by others, it kept causing disasters all over the place.
So in April nineteen sixty six, there were two different,
just that one month, two different enormous, highly fatal nitroglycerin

(15:37):
accidents in the Western Hemisphere. I was reading about these
both of these accidents on a digital exhibit about railroad
history hosted at the Linda Hall Library of Kansas City website.
So the first incident was on April third, eighteen sixty six.
There was a steamship loaded with seventy crates of nitroglycerin

(15:59):
among other carb cargo, sitting in a harbor in Panama.
I think it was eventually bound for California, but it
exploded while while tied up at the dock, and that
killed around fifty people. And then just a few weeks later,
a roughly three hundred pound crate was awaiting delivery at
a Wells Fargo office in San Francisco when the workers

(16:22):
noticed that it was leaking some kind of oily fluid
onto the floor, and this kicked off an inquest about
whose fault it was that the crate was leaking. So
workers at the office got a hammer and they started
trying to pry open the box to see what the
damage was, and the process of opening the box caused
an explosion that completely destroyed the building and killed fifteen people.

Speaker 4 (16:45):
Nikes.

Speaker 3 (16:46):
So yeah, horribly dangerous stuff and these mechanical shocks jostling
could set it off and then the results are horrible.
But eventually, after a lot of continuous work, no Better
Well figured out some methods for making nitroglycerin usable by
making it less dangerous and temperamental. And one of the

(17:09):
most historically significant of these solutions involved diatomaceous earth, which
Nobel knew under the name the German named Kieselgre. Now
there's another invention relevant to nitroglycerin that Nobel came up with.
It's just as important, called the blasting cap, which was
a two stage ignition or detonation device for nitroglycerin. This

(17:33):
was created to solve a problem which was that, ironically,
despite the fact that nitro would often explode when you
didn't want it to, sometimes it wouldn't explode when you
did want it to. So, for example, you could not
just run a traditional fuse to a massive nitroglycerin the
way you'd run a fuse to a massive gunpowder to

(17:55):
blow it up. You run a fused to nitroglycerin, and
some sometimes the presence of fire would simply result in
the surface of the nitro catching fire rather than in
what you want, which is the sudden release of all
of the nitroglycerin's energy in an explosion. The blasting cap
got around this problem with a clever design. So it

(18:17):
was a multi chambered, multi explosive plug that used a
fuse traditional fuse to ignite a primary explosive like mercury fulminate,
and the explosion of that would cause a shock wave
that would reliably trigger a second chamber of nitroglycerin to explode.
So fuse ignites the primary, the shockwave from the exploding

(18:41):
primary detonates the nitro.

Speaker 2 (18:43):
Okay, So the blasting cap innovation does not in any
way make the nitroglycerin safer or more stable in terms
of like keeping it from randomly blowing up or seeming
to randomly blow up, but rather it just makes it
more reliable when you do want it to blow up.

Speaker 3 (19:00):
The major safety and stability innovation comes in with the
diatamacious earth the keesel gore. So, how does that come in?
Nobell figured out that if you mix liquid nitroglycerine with
keyesel gore, so with diatamacious earth, the ground up fossilized
skeletons of this ancient algae, you end up with a
multiple paste, which is useful for multiple reasons. One is

(19:23):
that as a paste, you can shape it however you want,
so you can like shape it into rods. You're probably
imagining when you think of dynamite a cylindrical stick, and
that is actually useful because you can if you're blasting rock,
you can drill holes in the rock and insert the
sticks into the holes.

Speaker 2 (19:43):
A big downside, though, is that a cartoon character might
stick one in their mouth thinking it's a cigar or
a cars for a light.

Speaker 3 (19:52):
Yeah, that you don't want to get it mixed up
with carrot. But the other major change, or the other
major thing that makes this pay very useful, is that
it is far more stable than liquid nitroglycerin, less sensitive
to physical shocks, and less prone to random explosions. So
by absorbing the liquid into this porous dust. You prevent

(20:16):
physical actions like sloshing, which can happen with liquid nitro glycerine.
Slashing is really bad. That can be you know, that
can make it blow up. And I think I think
sort of the way it works, based on what I've
been reading, is that you generally limit the propagation of
mechanical shocks through the material by turning it into a paste.

(20:37):
So you just make it less prone to unwanted chain
reactions from shaking and jostling. If you picture like a
bottle full of just liquid, you know, oil or water
clear bottle, and you like flick the side of the bottle,
you can see waves rippling through the liquid inside. It
will propagate, you know, the impact will propagate through the liquid.

(20:59):
It's kind of hard to imagine waves rippling through a paste.
You're not really going to see waves propagating. Mechanical shocks
in a paste are absorbed and contained locally by deformation
of the paste. So that's, to my best understanding, one
of the main mechanisms of how it becomes safer in

(21:19):
paste form. So anyway, this combination of nitroglycerine and diatamacious earth,
which Nobel patented in eighteen sixty seven is what became
known as dynamite. Dynamite comes from the word dynamite comes
from the Greek word for power dynamies, So dynamite is
like the paste of power. And though I don't know

(21:43):
if this was intentional, I do like also that eight
is the suffix we often apply to like a mineral
or a rock, so you could also, I don't know
if Nobel meant it this way, but you could also
think of it as like the rock of power.

Speaker 4 (21:57):
Oh nice.

Speaker 3 (21:58):
Together with the invention of the blasting cap, dynamite paste
was a revolutionary material throughout multiple industries. And a funny
note on the name I think I also read this
in that history dot Com article. No Bell had been
trying to shake the bad reputation that followed nitroglycerin and

(22:19):
followed him after like all these infamous deadly explosions, and
so to put people's fears to rest, he initially wanted
to call dynamite quote Nobel's safety blasting powder.

Speaker 2 (22:32):
He can imagine the label, Yeah, Nobell's safety blasting powder,
not for military use.

Speaker 3 (22:37):
Yeah, So the name did not stick, But if it
had the safety in the safety powder would come in
large part from the dietamacious earth. However, I do want
to note that diatamacious earth is not the only substance
that can stabilize nitroglycerin in this manner, So a lot
of absorbent powders and materials will work the same. And

(23:01):
I and I believe many subsequent dynamite preparations used other
absorbent solids like sawdust or paper pulp, which work as
well or better. But dietom skeletons were there first.

Speaker 2 (23:23):
All right, Well, you know, since we're talking, you mentioned
the absorbent qualities of the diatamacious earth, So let's let's
talk about another big one previously kind of invisible to me.
There are various diatomic products out there, you know, toothpas
for example, and so forth, but in any number of

(23:44):
industrial and product based uses. But a big one that
I was that I was completely unaware of is cat litter.
So to refresh your indoor cat, if you have one,
or your friend's indoor cat, whatever your exposure level to
these feel lines happens to be. These are creatures of
the desert, and being a creature of the desert, they

(24:05):
require a miniature desert in your house in which to
do their business. The cat is a lonely hunter, but
it is also prey for larger creatures, so it adapted
to hide its urine and its feces in loose substrate
to mask its scent. You know, given you know that
they'll prefer to use something like sand or you know

(24:27):
what we think of a litter But of course they will,
as many of us cat owners know, they will also
try to use other things, be it a bedspread or
what have you, something where they're like, okay, I could
go here and then maybe disguise it, you know, falling
back on these these highly evolved practices that apply to

(24:48):
a dry environment.

Speaker 3 (24:50):
This is interesting. This is something I feel like I
should have already looked up and known the answer to.
But I didn't really know. Why do cats I mean again,
not all cats, that's all the time, but why generally
do cats know to use the litter box without training?
So you put out cat litter, cats go to the
litter box and do their business there. That seems strange.

(25:11):
I guess I would have assumed there's some kind of
smell or scent that manufacturers add to it that attracts
the cat, but you're saying it's more of an evolutionary
attraction to doing their business in a sandy or gravelly
substrate because that's yeah, okay, so that is their natural
tendency is to go in the sand. So if you

(25:31):
only have sand and sand like substance in one place
in your house, that's where they'll go exactly.

Speaker 2 (25:36):
Yeah, yeah, that's that's what's going on. And it's really
I was thinking about it the other day. I mean,
I think about the litter box every day because I
scoop it every day, but sometimes multiple times a day.
But it is one of the great things about a
domestic cat, a house cat, an indoor cat, but also
a frequent pain point because on one hand, it's like
it's basically a miracle because, like you say, you can

(25:59):
bring in a cat and for the most part, it's
just going to know to use the litter box or
use a litter box instead of all the various places
that it could be messing up with. It's urine and
it's fecal matter. Not to say they won't still get
fecal matter or you're in elsewhere in the house, they
absolutely will, But on the whole it will be isolated

(26:20):
to one spot.

Speaker 3 (26:21):
It's a miracle. Really. Yeah. Imagine if you had to
train a cat where to go to the bathroom.

Speaker 2 (26:26):
Yeah yeah, yeah, I mean some people do. That's a
topic for another time, but yeah, it's pretty amazing. But
of course it is also one of the pain points
of owning a cat, because you've got to scoop the box,
you've got to clean the box. And even though cats
are rather clean creatures, they can still make a litter
box pretty foul for a number of reasons, many of
which we can't really blame on them. They're interfacing with

(26:48):
the technology that they did not invent it. We did
so briefly about the invention of cat litter as a whole.
So prior to around nineteen forty seven, owners either of
course didn't use litter, as cats were primarily outdoor creatures
or the very least indoor outdoor. The advent of the

(27:08):
true indoor cat is relatively recent, and if they were
going in some sort of a substrate that was provided
for them, people would use sand, they would use ashes,
sawdust or something like this. And then in forty seven,
a man by the name of Edward Lowe who lived
nineteen twenty through nineteen ninety five is generally regarded as

(27:31):
having invented the first cat litter made of clay, basing
it off of what he knew regarding industrial absorbent materials. So,
you know, knowing that, okay, if we have some sort
of a spill and a factory, there are certain things
we can throw on that to help absorb the moisture
and you know, aid and clean up. And he began
to apply some of that to the cat cat box situation. Now,

(27:57):
clumping cat litter comes later. Most of us were familiar
with some sort of a clumping cat litter. I remember
I have had some friends that were themselves not cat owners,
and they volunteered to cat sit for another friend. And
I remember stories of one of these individuals being rather
shocked by the clumps that they were having to get

(28:19):
out of the litter box, like they didn't know what
they were. They were like, what is going on here?
This is weird. Cat's going in the box leaving behind
poop and big balls of clumped material. This comes later.
This is like a nineteen eighties innovation via moisture locking
minerals that are added into the mix. So yeah, we
end up in the age of litter and the pros.

(28:40):
You know, cat will use the bathroom on its own
time in a designated space. You don't have to walk
the cat. Depending on conditions and individual cat personality, the
cat might even bury what it leaves in the box.
Your experience may vary out there. My current cat, Mochi,
generally does not bury anything she may and again this

(29:03):
is not entirely on her. Cats are following certain programming.
The cat will do something like go in the box
and then like scrape on the top of the box
like do the digging motions somewhere or in some manner
that doesn't actually bury anything. So you know, like she's
going through the motions. It's not her fault that. Again,
this technology is weird, and maybe the litter boxes should

(29:25):
be much larger, I don't know, but you know, we
make do with what we got.

Speaker 3 (29:31):
Many's kind of like when if you've ever seen people
out walking their dog and they they like stoop down
to pretend they're picking up the dog poop. They don't
really pick it up.

Speaker 2 (29:42):
Well like that, but without intent. It's like if that
person were just like so distracted that they were just
going through the motions of picking it up. I guess
there are some things that humans do kind of like
if you ever find yourself going to put dirty dishes
in the laundry hamper or or our dirty laundry into
the swasher, and you're like, what am I doing? I
guess it may be on some.

Speaker 3 (30:03):
Level like that. Cats have a lot on their minds.

Speaker 4 (30:05):
Yeah, yeah, yeah.

Speaker 2 (30:07):
And the other great thing about cat litter is that
many forms of litter will rapidly dehydrate fecal matter and
cause urine to clump into those easily scooped clumps. So
in general you're just left with a dryer clean up area,
so like a cleaning up. This is, you know, an
overstatement of the obvious, but it is so much more

(30:27):
pleasant to clean up partially or wholly dehydrated cat crap
and certainly clumped cat urine as opposed to say, a
puddle of it. I've cleaned up all of these things,
all the different forms of urine and cat fecal matter before,
and yeah, it's much easier if it's dried out.

Speaker 4 (30:47):
Okay.

Speaker 2 (30:47):
But the big cons of course, is that all litter
box choices are subject to cat approval. All litter box
arrangements are subject to change at any moment. New litters
that you may try to gradually introduced could be just
rejected out of hand or gradually rejected. This I've encountered
many times before we're like, let's let's try a different litter,

(31:09):
and I'm always like, yeah, let's do it. But you know,
the cat has to approve of it, so you'll begin
to change it over gradually, and a lot of times
this works. This is generally what's advised of cat owners,
like gradually change over to this different litter so the
cat can get used to it and you won't disrupt anything.

Speaker 3 (31:25):
But I mean, like you use a mix or something, yeah,
to like.

Speaker 2 (31:28):
Use a little bit of the old mix some of
this new mix and then gradually change the proportions until
it's just the new mixture. But I've had situations where
our cat will be like, no, this is not what
I'm going to poop in anymore. I'll pee in it,
but no more poop, or they'll just or they're just
up and decide this is not it anymore. Now it's
the bed in the guest bedroom.

Speaker 3 (31:46):
So Rob, can I ask I don't have a cat
and haven't had one for many years, But I have
a vague, long ago cat memory from family cats that
sometimes the cats attempt to be hygienic in burying the
material will actually create more of a mess because they
will end up kicking a bunch of cat litter out

(32:09):
of the box all over the room.

Speaker 2 (32:11):
Yeah, I mean this, there's a whole suite of problems
associated with and it varies depending on what kind of
litter you're using, Like, is this a letter litter that
the cat is going to, you know, kick out of
the litter box? Is the litter box constructed in a
way that enables us to happen more readily, or is
the cat going to track it out? Some litter litters
are more trackable and so forth. So yeah, they're they're

(32:33):
fastidious little creatures, but you know, they they still can
be quite foul, either accidentally or certainly as they get older.
So yeah, that's the other big con is that litter
boxes can still produce odor and or mess. They have
to be maintained, they have to be cleaned, and the
cat is only going to help you so much in
doing any of that. So cat owners, I think already

(32:54):
know this, But there are a variety of litters to
choose from out there. They range from clay baits clumping
litter that that that my that I believe that's the
kind of my cat uses and prefers. You also have
plant based, clumping and non clumping litters made from all
sorts of things like corn tofu. Newspaper is a big one. Uh,

(33:14):
this is this is pretty fascinating. Anyone out there who's
into growing their own mushrooms might be aware of this.
But there at least used to be one called Yesterday's
News as a cat litter made from newspaper and it
and something about the way that it was it was
manufactured and like the purity of it it was ideal
for growing oyster mushrooms out.

Speaker 3 (33:36):
Of Now, I assume you wouldn't want to cross the
streams there not like using it as cat litter and growing.

Speaker 2 (33:43):
Yeah, you wouldn't want to know absolutely, but but it
was apparently, uh you know, some some cat owners liked
using it, but also mushroom enthusiasts were fond of it
as well. And yeah, so so there are various other
litters as well. Crystal litters are really big now, you know,
to ones that were the color changes depending on what's
going on in the cat's urine. And then you also

(34:05):
have diatomaceous cat litter as well.

Speaker 3 (34:08):
Awesome.

Speaker 2 (34:10):
Yeah, so I have not personally, or I certainly have
it personally, but my cat has not tried out diatamacious
cat litter. But this is to understand typically food gray
diatamacious earth that offers natural odor control and is often
sought out for being a physically lighter alternative. This is
of course one of the big things about cat litter

(34:30):
for using like a like, especially like a clay based
This is like a big tub, a big heavy tub
you have to bring into the house every so often,
and it's not necessarily a workout you want to incorporate
into your weekly life.

Speaker 3 (34:44):
But as we've talked about, diatamacious earth tends to be
very low density. Yeah, so for us, you know, it's
made of these kinds of cages with lots of little
hollows in the grains.

Speaker 2 (34:53):
Yeah, so much lighter, much lighter. And then indeed, that's
one of the appealing things about different non clay litters.
It's like, oh it's lighter. Maybe I can get it
shipped to me. You know, it's just gonna be less
of a hassle to carry. Other things about diatamacious cat
litter is that it's also generally chemical free and considered
non toxic. I'd be interested to hear what listeners out

(35:15):
there have to share if you've tried diatamacious cat litters.
But I think all of this makes sense given what
we've established about the substance. Now cat owners in general,
just looking around at some of the chatter online, they
seem to go back and forth on diatamacious earth litters
and diatamacious earth based litters. You know, some saying well, okay,

(35:36):
I'm worried about potential respiratory impact and so forth. I'd
say on any of that, you know, ask your vet,
or if you're worried about yourself, ask your your actual doctor.
But this is another This is another thing with litters
in general. Some litters they can throw up a great
deal of dust into the air. Lighter litters, too, might
track out a little more easily. So you know, there's

(35:59):
there's there's no perfect world here. There's gonna be some
drawback no matter what you're doing, because at the end
of the day, there is a small predatory creature that's
living in your house, and it is pooping in a.

Speaker 3 (36:10):
Box, And so wouldn't it be cool if it was
pooping into the trillions of fossilized skeletons of ancient algae.

Speaker 2 (36:18):
I think it would be fitting, given that these are
tiny little predators who seem very very high and mighty
at times. You know that they venture into this mass
grave of prehistoric organisms, and that is where they do
their business, you know, on pyramids of fossils.

Speaker 3 (36:34):
Poop on the graveyard of eons past.

Speaker 5 (36:36):
Yeah, okay, So I wanted to talk about just a
few more quickly, a few more human uses of dietamacious earth.

Speaker 3 (36:54):
Ranging from the weird to the mundane. Though again they're
all pretty weird when you think about what dietamacious earth
is these fossil skeletons. So one I alluded to briefly
in the last episode is filtration. Diatamacious earth is often
used to filter unwanted solids out of liquids. So, for example,

(37:16):
one major use is in pool cleaning systems. You know,
if you have a pool has a filtration device and
you can use different types of media there. So I
think some just use like sand, But diatamacious earth is
a popular choice there, but it's also in its food
grade form used in the production of foods and beverages,
for example, wine and beer. Pure dietamacious earth is considered

(37:40):
a good choice for filtering drinks like this because it
will catch and sive out suspended particles. In the case
of beer, this can include yeast and other particles of
like proteins that can cause cloudiness or haziness in beer.
In some beers, you know you want haziness. That's a

(38:01):
In some cases that's a property you're trying to retain.
In other cases, you want to filter it out and
increase the clarity of the beer.

Speaker 2 (38:07):
I've seen beers with names that invoke haziness as being
an important part of their personality.

Speaker 3 (38:14):
I mean, I like a hazy beer, but I also
like a clear beer. You know, it's different, different different
beers for different years.

Speaker 2 (38:21):
I'm only clear if I am having a beer, it
needs to be so clear that I can see the
person on the other side of the table through it.

Speaker 3 (38:27):
Well, I think then you're probably drinking some beer that
has gone through some fossil Fossil dietm skeletons. It's not
the only filtration system used, but it's a common one.
So if you picture this process at the microscopic level,
you're gonna have the liquid dripping through and you just
imagine particles of yeast and the other floating objects becoming

(38:51):
caught in the cages and crags of these machine elf
gears as the liquid is going through it. It's useful
because it's good to you for filtration because, as you
were just talking about with the cat litter, it is
chemically inert. Basically it's glass, so it's not going to
be chemically reacting with what's passing through it. It doesn't

(39:12):
really add a taste of its own. This, of course,
is provided you are using correctly food grade ditamacious earth.
Use the wrong kind and you could add weird flavors
in addition to introducing safety issues. So I have to
use the food grade kind, and based on what I
was reading from Brewers, the biggest advantage dietamacious earth seems

(39:35):
to have over membrane based filters is that you can
pass a lot more liquid through it before it effectively
becomes clogged.

Speaker 2 (39:43):
If this is of course, this is going to be
a no brainer for a lot of people, but generally,
when you're dealing with any kind of filtration system, it
will reach a point where it cannot filter anymore because
it is filled of the stuff you're trying to filter.
This is why if you have a filter for say
your water supply in your refrigerator, that's why that needs
to be changed out every so often or not used.

(40:06):
Like it's either use it and replace it or don't
use it at all.

Speaker 3 (40:09):
Right, Yeah, Another common use of dietamacious earth is as
an abrasive, so it's used as a mild abrasive and
different kinds of polishes. This is true and everything from
like you'll find like jewelry polishes that use dietamacious earth
polishes for metal working, and in some kinds of toothpaste.

(40:30):
I think at least it's not going to be in
all of them, but at least some brands of like
the gritty polishing paste that you get at the dentist,
you know, and they were.

Speaker 2 (40:38):
Run and taste like hopefully mint. But also if you're
un lucky cherry or chocolate.

Speaker 3 (40:43):
You never got bubblegum.

Speaker 2 (40:44):
I have had bubblegum before. This is one of the
about the only things I can talk about with my hygienesis.
I'm like, what flavor do we have coming up? Hopefully
they'll say meant and you know after that you just
have stuff in your mouth the whole time.

Speaker 3 (40:55):
And you can't talk again. It's not all of them,
but like some brands of this kind of polishing paste
can use dietamacious earth. A more cutting edge proposed use
with some pun intended here that I thought was really
interesting is a use of dietamacious earth potentially in future
first aid when you are rapidly losing blood. So I

(41:19):
came across a paper from twenty twenty two called diatamite
hemostatic particles with hierarchical porous structure for rapid and effective hemostasis.
This was published in the journal Colloids and Surfaces B
bio Interfaces. The lead author is named Changsu. A bunch
of co authors listed, and the researchers in this paper

(41:41):
showed that you could promote rapid blood clotting after an
injury with the use of a topical granular treatment. So
you have kind of a sand that you would are
a sand based treatment that you would put on a wound.
Though it wasn't sand, it was dietamacious earth. Though to
be clear, This is not just plain diatamacious earth straight

(42:03):
out of the bag. So don't think like it's a
good idea. Oh if I get cut, I'm going to
reach into the bag and cram ditamacious earth on the
It was specially prepared product that had gone through a
process to enhance its blood clotting capabilities. The product they
created was called diatomite hemostatic granules, and so in a
model where they used these granules for treating amputations and rats,

(42:27):
the granules caused rapid coagulation without toxic side effects. And
it seems like one of the major advantages here is
again this absorbent the porous absorbent qualities of diatamacious earth,
the ability to absorb fluids. This seems to sort of
concentrate the platelets at the blood at the exposure, at

(42:50):
the place where the cut is or the wound is,
and again promotes rapid clotting. And I think this is
related to a lot of these other uses. One thing
I didn't really get into, but it's sometimes used to
clean up spills. You know, dietamacious earth because it has
this absorbent quality, you can kind of soak things up
in various situations.

Speaker 2 (43:09):
So diatomite hemostatic granules, not for do it your self use,
but maybe in the future, and certainly if you're writing
some science fiction and you want to jazz up your
your healthcare first aid scene, yeah, run with it.

Speaker 3 (43:25):
I could imagine. Yeah, in the future, So somebody on
the alien planet, they get their arms sliced off by
a laser, and so you just cram some of the
some of the diatamite sand on there and it seals
you right up.

Speaker 2 (43:37):
All right? Would you like to talk about some going
back to the organism level of things, Do you want
to talk about some diatoms of interest here?

Speaker 3 (43:46):
Absolutely? I would love to look at some of these
weird little guys.

Speaker 2 (43:50):
Yeah. We talked a little bit about specific varieties and
species in the last episode, and as we close out
this episode, I just wanted to talk about a few
that turned up in my research as being particularly interesting
for one reason or another. A lot of this is
just how they look, you know, like why does this
one look like a star? Why does this one look

(44:12):
like a tube? Why does this one look like a gear? Again,
there's so much variety, so much visual variety in what's
going on and sometimes that does seem to cross over
into their functionality as well in fascinating ways. The first
one I want to talk about here is Corathron castra
khani previously known as corathron cryophillum castra khani. This one

(44:38):
is a spiky diatom, sometimes compared to a mace, though
I think that's a bit of a stretch trying to
infuse a little medieval warfare into it, because when I
see it, I think, okay, Chinese finger trap, which by
the way, is a toy of non Chinese origin, but
everyone knows what I'm talking about, a Chinese finger trap,
but with spikes I see.

Speaker 3 (45:01):
I see a vacuum tube with tentacles.

Speaker 2 (45:03):
Yeah, yeah, that's that's more the vibe I get.

Speaker 3 (45:06):
Unless something that came out of the back of a
guitar amplifier and but then came alive and is now
it's also the thing.

Speaker 2 (45:14):
Yeah, yeah, a little bit for sure. Yeah, definitely a
strange looking thing. Maybe not the most exotic of diatoms
if you just looking at an illustration with a bunch
of them, but once you really start looking at it,
it is a weird one. So we're dealing with the
marine plectonic diatom genus here, and one that's pretty widespread
today and in the fossil record back as far as

(45:37):
the Cretaceous period. This according to this I was reading
about in the intriguing marine diatom genus corethron in late
Cretaceous amber from Vendt, France by Martin at All, published
twenty fifteen in Cretaceous Research. The interesting thing here is
that the fossil evidence of this particular organism it shows up.

Speaker 3 (46:00):
In amber, oh like in Jurassic Park.

Speaker 2 (46:03):
The authors described this as a special case of biostratinemy.
This is a fancy term for the study of an
organism's remains after it dies. And they say that this
is a case quote where a marine taxon is incorporated
into the liquid resin produced by trees. Implied that the
Vendine amber forest grew in a near shore environment where

(46:25):
wind sea spray or high tide introduced the marine diaton
frustules into the terrestrial realm.

Speaker 3 (46:34):
WHOA, Okay, So if I'm understanding this right, they're saying
that the fossil amber is going to be something that
came out of a plant like a tree. Maybe the
resin before it got hardened, and so it comes out
and it's this sticky substance and it is somehow getting
seawater incorporated into it. So maybe it's at the shore

(46:54):
and it's getting sprayed by the waves, or there's a
flood and it gets seawater on it. Somehow out the
seawater gets onto it, the seawater has these shells of
the diatoms in the water, and thus it gets incorporated
into the fossil amber.

Speaker 2 (47:09):
That's right, Yeah, okay, so pretty pretty amazing awesome. Yeah,
So that in and of itself was worth focusing on.
But there's more interesting about this. This this type of organism,
the corthron, is the only diatom genus that features separate
movable components spines of the cell wall. The authors point

(47:29):
out that all corthron species can move at least to
some degree, and that the movement is mechanical, as these
spines are outside of the.

Speaker 3 (47:37):
Cell wallh Okay.

Speaker 2 (47:40):
Again, coming back to what we talked about before, where
with diatoms we're talking about a single cell organism. We're
looking at a cell. Yeah, so this their cell body here,
this tube. It has a valve at either end, one
circled by long spines with tiny barbs, and the other
has these short hooked spines, forming what is sometimes called
a crown or described as a crown, and the hooks

(48:03):
lock the spines in place, apparently until the organism reaches maturity,
and then the spines swing out seemingly to quote keep
cells apart or serve as a physical defense against zooplankton
that you know might eat them.

Speaker 3 (48:18):
Oh okay, so it's it's got some weaponry or defensive mechanisms.

Speaker 2 (48:22):
Yeah, in a very kind of basic sense, you know,
just sort of like creating space with spines. That's sort
of yeah.

Speaker 3 (48:29):
Okay.

Speaker 2 (48:30):
The way that the silica spines are attached to the
dome shaped valves, though, is sometimes described as very much
being a ball in socket style joint. You can look
up imagery of this. I included an example here from
a study Joe for you to look at, and folks
at home you can look up at the examples of
this as well by just doing a Google search. But
you do, yeah, you do get this sense of like

(48:52):
a ball in socket sort of joint. So it's pretty amazing.

Speaker 3 (48:55):
Okay, So is that how if I'm understanding this right,
that's how the spines kind of move on the outside
is Yeah, they have a they are loosely attached at
the opening, but they have something, a thicker element behind
the opening that keeps the spines from falling out.

Speaker 4 (49:11):
Correct, Yes, okay, all right.

Speaker 2 (49:23):
For the next one I want to talk about, there
is Basilaria pack Silafer. This one is also very fascinating.
This was very interesting to look at visually, at least
if you're looking at a bunch of them, a colonial
assortment of them. So this is a because this is
a colonial diatom with a unique form of movement. Individually,

(49:46):
they are not very interesting. Each one of these looks
maybe like a toothpick. I've seen them described as looking
like pegs. They're just long and narrow. They look like
little sticks.

Speaker 3 (49:56):
Yeah, long, thin, wand yeah.

Speaker 2 (49:58):
Yeah, so noting, nothing really remarkable in that. But they'll
align parallel with one another to form these colonial formations
that look very mechanical.

Speaker 3 (50:08):
Yeah, okay, so they're all lining up side by side,
and what originally was like a toothpick becomes kind of
a row of toothpicks and takes on this look like,
I don't know, the expanding part of an accordion, maybe
or like blinds or something.

Speaker 2 (50:24):
Yeah, blinds. That's a good example, a good way to
think of them. I was trying to think, well, what
is this reminding me of? And I think it was
reminding me a bit of collated framing nails, you know,
where you'll have like the nails that are kind of
like stuck together with this stuff and they kind of
like line up parallel to each other.

Speaker 3 (50:42):
Okay.

Speaker 2 (50:42):
Or perhaps I'm thinking about some sort of licorice. Maybe
there's a licorice out there that I'm only half remembering
that has this kind of formation. So the crazy thing
about this formation is they're not just again, this has
to do with how they end up moving as a group.
So in this formation, they're able to slide against the neighbors,
and they can coordinate these movements in their own way

(51:04):
to move the entire formation by compacting it and expanding it.

Speaker 3 (51:09):
Okay, So each individual dietom is its own single celled organism,
but they group together into these colonies, these groupings, and
as a group they are able to kind of expand
and contract in a way that moves the whole group.

Speaker 4 (51:25):
Yes.

Speaker 2 (51:26):
Yeah, And one of the fascinating sort of science world
things about this is that this is mentioned in like
the Wikipedia article about this type of diatom, but I
dug into it and found the paper where it was
being discussed in detail. This diatom has its own dance,
its own dance that some human scientists have performed on occasion,

(51:49):
though I'm not sure if it's recommended that scientists do
this at any conferences today. As we'll discuss, it was
acceptable in the eighties. It was acceptable. This was detailed
in the Colonial Diatom Basilaria Paradoxa. This was by using
it all, published two thousand and five, and it is

(52:11):
referring back to something that would have occurred in I
believe nineteen eighty seven, and this would have been at
the North American Diatom Symposium or NADS. The dance was
allegedly invented by Edward C. Theiat and p Rogers Sweets. Okay,
so this basically involved We already talked about the way

(52:32):
that the diatoms move colonially. This basically involves biologists in
varying states of sobriety lining up next to each other,
I think like front to back sort of a situation,
lining up with each other like this, and then rubbing,
moving against each other in order to move like colonial diatoms. Okay,

(52:53):
this paper that I referenced, they include an interview snippet
with the biologist theiat who had produced some footage of
the organism's movements prior and like this led into the
different biologists trying it out. So reading from this interview
snippet in this article, he says, quote choreography was very basic.

(53:14):
Chant do the bas cellaria? Do the basilaria up in
tone on the first, uh down on the second. During
the chant, everyone slid tightly against the next person front
to back. As I recall, central nodule job was to
try to keep both ends moving at approximately the same rate.

(53:35):
And I'll point out, he notes later, there would be
no such role for the actual diatoms. There is no
leader for the diatoms, but they're just trying to sort
of physically recreate the movements here, he says, as we
got more practiced at it, we tried to move everyone
but at different rates, much like a real basilaria.

Speaker 3 (53:54):
The dance. Cause, I do admit I'm having a little
trouble picturing how the movement happens.

Speaker 2 (53:59):
But yeah, and it's worth noting here that the dance
caused some of the drunker or less coordinated dancers to
fall down on the floor fall out of the arrangement. Also,
some of the dancers were going to be were more
comfortable with this dance because they're having to rub up
against their neighbor, and in many cases like maybe that
neighbor is a significant other other times I guess it's

(54:20):
maybe a stranger. In general, I realized today this sounds
like an hr nightmare. But apparently at the time in
eighty seven it was acceptable. But they said they tried
it again at the Finland International Diatom meeting, but quote
it did not have the same magic.

Speaker 3 (54:38):
The moment's gone.

Speaker 2 (54:40):
So I don't know if biologists are still doing this
at any diatom symposiums out there. I imagine there's a
lot more paperwork involved if you do.

Speaker 3 (54:48):
I guess if it's on a volunteer basis.

Speaker 4 (54:51):
Yeah.

Speaker 3 (54:51):
Yeah.

Speaker 2 (54:52):
One more thing about Busselaria here, and I realized I
may have pronounced it like three different ways, but is
the author's going out Like The really fascinating thing about
its movement is that it moves like a segmented organism
in some respects, but each segment is an individual. So
what we have here is synchronize mechanical behavior in single

(55:14):
cell organisms.

Speaker 3 (55:16):
Interesting.

Speaker 2 (55:17):
Yeah. The final one I want to talk about is
a plankton Alis soul. This one is just this one's
very beautiful to look at because it looks like a
like a solar disk, or some describe it as looking
like a maybe like a nineteen fifties UFO is seen
from above.

Speaker 3 (55:33):
I was going to say, it's it's the wicker Man.
We have the face of Nuada here.

Speaker 2 (55:37):
It does kind of look like New auDA. Yeah, yeah, yeah,
it's one that's going to stand out if you look
at some of these illustrations of various diatom species. But
it's also one of these where if you don't know
what you're looking at, it's easy to miss. Because we
know that diatoms are cells, so it would be easy
to assume that we're just looking at a cell.

Speaker 4 (55:56):
Here.

Speaker 2 (55:56):
It's round, you know, it has different parts to it,
and maybe you don't remember all the parts off the
top of your head, and you're like, okay, there's the cell,
but the central part of it, well you might think
of the is the yolk of this fried egg. This
is the diatom cell. Meanwhile, the egg white part is
essentially a sale, and we see these structures kind of
holding the sale out as well. And this segment, this

(56:20):
wide of the egg on this particular diatom, this is
called the corona, and it is a ribbed extracellular matrix
that does act as a sale. So the corona increases
its surface area with this structure, and it allows it
to catch and travel on ocean currents more easily. So,
you know, something so small, we don't think about it

(56:42):
so much, but yeah, it is having to essentially sail
around in its watery environment. This seems to be a
very successful design because this particular type is widely distributed,
common in tropical and subtropical waters, but with possible greater
temperature tolerance in general. Apparently that's something that scientists are
still studying. But it does not have a signature dance.

(57:06):
That's that's worth noting as well.

Speaker 3 (57:08):
But if it did have a dance, I think it'd
be the wicker Man dance Christopher Lee is doing at
the front of the parade with the yeah yeah and
some japes.

Speaker 4 (57:15):
Man.

Speaker 2 (57:16):
I think he does some spinning around, you know, he
does make sense.

Speaker 3 (57:19):
Yeah, absolutely, Okay, well does that do it? For part two?
Are we going to come back for one more episode
on diatoms? I believe, we move on to something else.

Speaker 2 (57:28):
I believe, so we have a little more history to cover,
we may have some more specific types of diatoms to discuss,
and who knows what else, because again, its uses are
so widespread, so specific at times, so mundane at times,
but also fascinating in the way that again, these kind
of this kind of you know this, this dead soil

(57:51):
leftovers of these little tiny glass shelled creatures, you know
they they end up playing an important but almost role
in so many aspects of our lives.

Speaker 3 (58:02):
Yeah, okay, well more next time.

Speaker 2 (58:05):
All right, we'll go and close it out. But reminder
to everyone out there, wherever you happen to get our podcasts,
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(58:28):
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Speaker 3 (58:43):
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Watch us on Netflix, listen on audio, just get us everywhere.

Speaker 2 (58:49):
I mean, I'm not going to tell you not to,
so just a reminder that Stuff to Blow your Mind
in general is a science and culture podcast with core
episodes on Tuesdays and Thursdays, short form on Wednesdays, and
on Friday Days Weird House Cinema. That's when we set
aside most serious concerns and just talk about a weird film.

Speaker 3 (59:05):
Huge thanks as always to our excellent audio producer JJ Posway.
If you would like to get in touch with us
with feedback on this episode or any other, to suggest
a topic for the future, or just to say hello,
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your Mind dot com.

Speaker 1 (59:27):
Stuff to Blow Your Mind is production of iHeartRadio. For
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