September 18, 2025 • 52 mins
In this episode of Stuff to Blow Your Mind, Robert and Joe discuss the giant clam and the many inaccurate myths, legends and traditions about their propensity for chomping down on or swallowing human beings.
See omnystudio.com/listener for privacy information.
Mark as Played
Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:03):
Welcome to Stuff to Blow Your Mind production of iHeartRadio.
Speaker 2 (00:12):
Hey you welcome to Stuff to Blow Your Mind. My
name is Robert Lamb.
Speaker 3 (00:15):
And I'm Joe McCormick.
Speaker 2 (00:17):
And in this episode, we're gonna be diving deeper on
a topic that we first explored just a little bit
on an episode of Automilia Stupendium, which of course is
one of our shorties that airs on Wednesdays, and that
is the subject of the Giant Clam. I found this
to be a fascinating topic to explore because, on one hand,
the giant clam is just an amazing organism, notable not
(00:39):
only for its size but also for its unique symbiosis.
But in addition to this, it's an organism that has
continually invited creative but highly inaccurate ideas about how they
actually behave.
Speaker 3 (00:52):
It's not hard to see why people might look at
this thing and think that it will bite you, because
it just looks like the whole thing is just a
pair of jaws like cartoon teeth.
Speaker 2 (01:03):
Yes. Yeah, And as we'll be exploring, I think the
really interesting thing here is that you see this, this idea,
this interpretation resonating not only with people who don't know
any better. Who are you know, one or multiple degrees
away from this organism and its natural habitat, but also
people in close proximity to it, or just can be
(01:24):
overwhelmed by the fact that it looks like a big mouth.
What if it was like a big mouth? And what
would the consequences of that be. The most pervasive idea,
of course, is we're talking about the idea that a
giant clam might latch onto your leg while you were
diving or snorkeling, or even in a very cartoon sense,
swallow you whole. And to be clear, just to go
(01:46):
ahead and get this out at the top, this has
never happened. There's no recorded evidence of it ever happening,
and for reasons we'll discuss, very good reasons. It pretty
much never could happen. That's right.
Speaker 3 (01:58):
There's like one real famous anecdote of a guy claiming
that it happened, and he was there and I saw
one of the babies and the baby looked at me.
There are strong reasons for thinking that this story is
not true, and other than that, it's mostly just vague
generalizations from people not citing any evidence or fictional storytelling.
Speaker 2 (02:22):
Right, right, Ben. You know that there are all sorts
of things that can go wrong in the water, and
there are lots of ways you can become injured and
so forth, but this is not really one of them.
And I think if you were gonna, if you were
going to pin your death on a giant clam, it
would be like you would have to essentially like strap
yourself to the giant clam and die drown underwater. You
(02:43):
would have to frame it in a major, insignificant way.
So yeah, in some ways, this I think is reminiscent
of our recent look at manta rays in the ways
that European sailors in particular misinterpreted the great fish as
a threat. But again, the curious thing about the myth
of the man eating clam is that while you only
find it circulating in the nineteenth and twentieth century among
Europeans and Americans, the idea also exists among native peoples,
(03:08):
who would have had more hands on understanding of what
these creatures were all about. But again, we're susceptible to
on one level, the kind of creative thinking, like you know,
this can occur separate from a logical interpretation. You know,
the idea that you know it's not a mouth, but
what if it is a mouth? And I think we'll
maybe get into a little bit about how maybe we're
(03:28):
just hardwired to see the jaws that could consume us,
even if we know those are not jaws. So yeah,
it just I think it might just boil down to
the fact that a giant clam, especially just looks too
much like a big old mouth for us to move
past it.
Speaker 3 (03:44):
And if you've never seen one of these, by the way,
you can look up a giant clam or tridacna clam
tridac na. These things have a waviness to their shells,
you know, the way the shell closes it. It is
not just a straight curved line across. It waves up
(04:04):
and down like a you know, oscillation of a sound
wave or something, which sort of suggests teeth and further
lends itself into the mouth interpretation.
Speaker 2 (04:14):
Now, speaking of mouths, it's interesting that tridacna apparently stems
from the Latin for three bites, and this goes back
to the writings of Like Plenty of the Elder and
even the Conquest of Alexander the Great, where it was
said that these could supply such meat as to require
not one, not two, but three bites for you to
consume it all. So the name actually originates in us
(04:37):
eating them, rather than any fabulous reversal on that.
Speaker 3 (04:42):
And people do eat them. By the way, A lot
of people believe the meat of this clam is a
is a delicacy. A lot of people think it's really delicious.
This has greatly harmed the clams. They are now in
a I believe, listed by the IUCN as a critically
endangered species, and there were efforts at combating this by
(05:03):
changing over some of the trade in their meat to
like farmed populations instead of wild populations, receding wild populations
and things like that. But yeah, people are definitely getting
some three bites in.
Speaker 2 (05:16):
Yeah, because they're an important part of coral reef environments,
the coral reef environments that they call home. Now, I
was excited to look into giant clams. I hadn't really
I didn't really have giant clams on my mind at all, because,
aside from maybe in the background, I had kind of
like a Looney Tunes idea of them, you know, swallowing
a diving bugs bunny or something to that effect. But
(05:36):
as I've previously mentioned on the show. Over the summer,
I had the privilege of visiting the islands of raja
Ampat in Indonesia, where rich diversity of marine life, and
this included the giant Tradacna clams, and of course the
biggest of all Tradacna geigis, and a particularly large one
in the area was known informally as Wu Tang clam.
(06:00):
And so I didn't get to dive right down to
Wu Tang clam because Wu Tang clam was like a
little deeper than some of the other than many of
the other giant clams I was seeing, but it was
still substantially large. And I included a photograph of Wu
Tang clam for you here, Joe. I'm I'm like ninety
nine percent sure this is Wu Tang clam. But this
(06:20):
is a shot from down there at its level with
proper lighting.
Speaker 3 (06:25):
Oh wow, yeah, just looking at this one image here,
it is so crusty with life all over it.
Speaker 2 (06:32):
It's hard to.
Speaker 3 (06:34):
See this as just one organism, as one clam with
its two valves, you know, slightly parted. It looks more
like a I don't know, a big piece of coral
reef for something.
Speaker 2 (06:44):
Well, that that underscores the reality here that yeah, they
are reef builders in the long term, like you know,
they settle, they grow there in one spot, and when
they eventually pass on for one reason or another, you
know they will be the bone of future coral reefs.
So yeah, that's one of the reasons they're so vitally
important to these environments.
Speaker 3 (07:06):
Another reason, I think, Rob maybe you can confirm this
because I guess you have seen them up close. I
think sometimes people might not recognize they are looking at
a giant clam, especially if they're like looking down from above,
because it's not you don't obviously see the shell. You
might just see a kind of ripply looking sheet of
(07:27):
the inner flesh of the clam, like the mantle protruding
from out of the shell. Because in a lot of
cases they will be perched somewhere in a kind of
sunlit sea bottom and they're trying to spread out and
gather sunlight on the fleshy parts. And we can talk
about the reasons for that in just a minute here.
Speaker 2 (07:45):
But you might not.
Speaker 3 (07:46):
Actually see something that looks like a clam. You might say,
what is this a big kind of flat ripple a
sea cucumber or something. Because you're just seeing the mantle.
Speaker 2 (07:55):
Right right, and the mantle tissue, it can be really
eye catching. Certainly saw this a lot with the various
giant clams that I was snorkling over. They almost feel
magical at times, seeming to pulsate with a strange energy,
and then they would as you would get near them,
they would sense you for reasons that I'll get into,
and the smaller varieties in particular would often kind of
(08:17):
like maybe not close all the way, but kind of tense. Yeah.
They were very vibrant to look at, and to your point, yeah,
they are. They are facing mouth up if you will,
because the mansle tissue needs to be, you know, have
maximum exposure to sunlight. Whereas the Looney Tunes version of
the giant clam that might eat bugs, bunny that you
(08:38):
tend to imagine it positioned less vertically and more horizontally.
Speaker 3 (08:43):
You're right, because it's like a crocodile's mouth.
Speaker 2 (08:45):
Yes. Yeah, So, as I was passing over these these clans,
the interesting thing is I still knew enough about clams
and giant clams to know that these things were not
a danger to me. They were not actually going to
try and bite me or anything to that effect. And
yet there is this undeniable resemblance to some sort of
(09:06):
a big fleshy mouth or secondary secondarily perhaps some sort
of yonic imagery. And so these associations I thought about
this fair amount as I was passing over them snorkeling, Like,
these associations connect with us, I think on a primal level,
and it's hard not to at least casually think of
(09:26):
what you're seeing in anthropomorphic terms, comparing them to basic
human physiological analogues and analogs that are like very closely
tied in to our survival and reproduction and so forth. Yeah,
mostly we're going to talk about giant clams as mouths.
But on the subject of yonic imagery, we do certainly
(09:48):
see interpretations of clamshells in general in the giant clamshell,
as well as vulva in its use as fertility emblems
as well as currency in some cultures in the past.
Sometimes you'll even see like Bodicelli's rendition of the Birth
of Venus sided in there as well, though the shell
that he depicts in that painting is a scallop shell,
(10:09):
I believe, and not actually a clamshell, but it is
presented on a scale that is more in keeping with
a giant clamshell.
Speaker 3 (10:19):
Though I think actually in that that's also bigger than
any known giant clam.
Speaker 2 (10:24):
Yeah, as we'll discuss giant clamshells, I think about the
maximum you're going to get is like four feet.
Speaker 3 (10:29):
Across, Yeah, which is very big, still very big.
Speaker 2 (10:32):
It's still enormous. But you know, they can't fit a venus. Yeah,
you couldn't fit a whole venus in there. You'd have
to really scrunch your up. Still seashells in general, you know,
pop up and Renaissance paintings, paintings sometimes with erotic suggestions
and their usage. Though quite incidentally, there is a venus
genus of clam. I was reading about this recently. Eighteenth
(10:53):
century Swedish naturalist and father of modern taxonomy, Carl Linaeus
famously described the venus claim in quite sexual terms, which
was pretty controversial at the time. Critics charged that he
quote indulged in obscene illusions. Suffice to say, it seems
quite a common interpretation, second only to the view of
(11:14):
the clam as a mouth.
Speaker 3 (11:15):
Was Linnaeus not otherwise really known for very expressive or
controversial descriptions.
Speaker 2 (11:21):
Correct. That's my understanding is that this was kind of
an outlier where suddenly everyone was like, whoa, whoa, what
are you doing? But you know, I guess the controversy
died down after a while.
Speaker 3 (11:33):
Yeah, it does seem like a biology is a funny
domain to get upset about that in.
Speaker 2 (11:39):
Yeah, yeah, all right, Well, speaking of biology, let's let's
let's go through some of the basics of the giant
clam here, particularly so again we're talking about for the
most part, we're talking about Tridacna gaigis, and it can
be found in coral reefs of the South Pacific and
Indian Oceans. They can reach sizes of up to two
(11:59):
hundred and fifty kerls are five hundred and fifty pounds,
and they can grow to somewhere over four feet or
one point two meters long or across. So again, maybe
not quite man swallowing size like we would see in
our fiction, but still incredibly big. Like they still look
like a they can still look like a massive like
(12:20):
bio chest there on the seafloor. Yeah. Now, the giant clam,
to be sure here, doesn't really have a mouth, especially
in the way, you might read it as again the
bugs bunny swallowing mouth. Instead, we have the valves, and
they are bivalves. Remember, so we have the like the
two shells that essentially howls the organism, and inside they
(12:45):
have a pair of siphons, one for drawing in food
and water and another for expelling waste. Furthermore, they are
filter feeders and they have no need for any jaw
like mechanics. There's no chewing that takes place with the
two valve. They simply close, or in the case of
the giant clams, nearly close their shells for protection. The
(13:05):
giant clams can't actually close them all the way for
a couple of reasons. And here's another big kicker. They
close their shells exceedingly slowly. One of the main predators
that they're closing their shells for protection against are sea stars,
which you are quite a threat to a number of
(13:26):
coral reef dwelling organisms. But they themselves are also slow
moving creatures. So for this very specific encounter, the closing
of the shell is actually pretty fast, but it's as
fast as it needs to be, and it's not man
catching fast.
Speaker 3 (13:42):
Yes, And the other thing you mentioned is they often
don't close their shells completely because you will still see
some of the flesh of the clam kind of protruding,
like they've got to both expel water and retract their
tissues inside in order.
Speaker 2 (13:56):
To close exactly. Now, the varied colorization of the mantle
tissues on the giant clam is due to ariticide cells
that feed light to symbiotic single celled dinoflagelet algae or zooxanthellae.
And this is where we get into the really cool
example of symbiosis going on here. The clam acquires these
(14:21):
zooxanthellae via constant filter feeding in the water, it also
acquires basic basic plectonic organisms that it actually eats, and thus,
during the day the clam is going to open wide
and extend its mantle tissue to absorb the sunlight necessary
for the algae to conduct photosynthesis, and in return, the
algae produced sugars and proteins that the clam needs to
(14:42):
survive along with its more traditional filter diet, which it
requires less off. So the giant clam has a dual
feeding strategy and this is thought to have evolved some
sixty four million years ago.
Speaker 3 (14:55):
Yeah, two different ways of eating. It is photosynthesizing with
the help of these organized that it has absorbed and
taken into itself. And then it's also filter feeding. It's
sucking through water and filtering out little bits that it
can eat.
Speaker 2 (15:08):
Yeah, and so that's that's one of the interesting like
observations you can make as you like snorkel over them.
Is like that mantle tissue is like it really seems engorged,
uh and and very out there because because it is,
it is, you know, collecting sunlight, and yeah, so fascinating
that it has this dual feeding strategy. The giant clam
(15:29):
also boasts thousands of pinhole eye spots along the mantle's
edge that allowed to detect changes in light, not only
the cycles of night and day, but also tailtale shadows
of approaching predators. And so this gets into you know,
the observation that I had as I was snorkeling over again,
the smaller of the giants, they would sometimes like tense
(15:52):
up a little bit. They wouldn't close all the way,
but there would be like a visual like rippling or
movement of the mantle tissue and even the valves. Yeah.
Speaker 3 (16:00):
Yeah, and I've seen video of the same thing happening.
If you say, you move your hand over the top
of one and cast a shadow over it, sometimes it
will kind of tense and partially close.
Speaker 2 (16:10):
Which, again the logical mind knows that, you know, it
is just responding to the presence of another organism, which
may or may not be something that is a threat
to it. But you also can't help but illogically read
it as like little mouths that are kind of going
at you, you know. So again, I think it's almost
(16:30):
impossible not to read them on additional levels as well.
Speaker 3 (16:34):
Yeah, well, I mean I think the way to think
of it is that what you're seeing there is a
retracting impulse, not a biting.
Speaker 2 (16:40):
Impulse, exactly. Yeah, it is a retracting not a biting
Because yeah, I think the other way we tend to,
you know, artificially think about them, and certainly in like
modern looney tune sense, is to think of them as
a bear trap. Yes, and we'll turn to some actual
examples from twentieth century cinema that depicts them essentially as
a bear trap just waiting down there for divers to
(17:03):
pass through it.
Speaker 3 (17:04):
Yeah, before we get to twentieth century cinema, there are
older stories of giant clams. As you know various forms
of monsters or man killers. The giant clam has appeared
(17:26):
in some myths and legends of various people's of the
Pacific Islands, sometimes as a benign creature, but sometimes as
a dangerous or monstrous creature. One interesting example I found
is in a to Amotuan version of the story of
the Polynesian hero Rata. I can't remember if Rata's come
(17:49):
up on the show before, but Rata is basically a
culture hero that you will find throughout Polynesian storytelling and
lots of different Pacific Island cultures. There are Rata stories
among the Maori, among Tahitians, to Emotuans, and others, sometimes
with a different name a slightly different name in different regions.
(18:11):
The Rata stories differ in many details, but the most
common elements are that he is a young, brave, resourceful
hero who has to go on a dangerous quest to
avenge the death of his father or to avenge some
other kind of crime against his family, and in doing
(18:32):
so he has to build a mighty canoe, which involves
felling a tree protected by spirits or magical beings of
the forest. Sometimes in older English sources these beings are
translated as elves or goblins. More recent sources, I think,
will call them things like forest spirits or something. But
(18:53):
once in this great canoe that he has made, Rada
has to go on a journey, sometimes with companions, to
avenge his family or avenge his father, and battle terrifying
monsters along the way. And so in one version of
the Rada journey, I found one of those monsters he
fights is a giant clam.
Speaker 2 (19:13):
So this is a.
Speaker 3 (19:15):
Telling of a version found among the Tuamotuan people of
the Tuamotu Islands and of Tahiti, told by a local
scholar named Taroi to a Missus Walker, and compiled into
a book called Ancient Tahiti by the British Tahitian folkloristan
scholar Tearia Henry, who lived eighteen forty seven to nineteen fifteen.
(19:37):
So I'm going to read the excerpt of the text,
and of course I have to apologize in advance for
any mispronunciations.
Speaker 2 (19:43):
I'll do my best.
Speaker 3 (19:44):
Here they were sailing on their course when the great
au or swordfish came into sight, and Rata mistook it
for land. But Tava said it was not land, but
another foe. So Rada stood prepared again for battle, and
when the monster approached the the canoe, intending to pierce it,
he killed it with his spear and presented the body
(20:05):
to the elves as before. Thus that demon was exterminated
and his flesh eaten by all. They sailed on, and
they met the great Urua, the Kavala fish, which looked
like land, but Tava told Rada it was the Kavala fish,
sent by King Puna to kill him. The fish darted
forward to carry away Rada, but he stood ready, and
(20:27):
as soon as it approached him, he thrust his spear
into its throat and killed it, and it was also
eaten by all. Next they met the great Pahua Tutahi,
a giant clam which appeared like a mountain looming up
from the sea. But Tava said, it is not land.
It is the giant clam, and Rada prepared for the
(20:47):
inevitable encounter. As his vessel was being drawn up into it.
The clam had opened its great valves and was sucking
in the waves upon which the canoe. Tua Rata was sailing.
Stood at the bow with his spear, and as soon
as they reached the center of the clam, he pierced
it through its vital part, severing its flesh from the
(21:08):
shell so that it could not close upon him. He
presented the clam to his spirit company to annihilate, and
as soon as the canoe was safely away, the dead
clam sank into the deep sea. So several interesting things
here in the story. It sounds like he's talking about
cutting the adductor muscle, which is something we see later
(21:30):
when people are talking about how to fight this clam.
In this case, it says that Rada, you know, he
stabbed it at its vital part with the spear. Severing
its flesh from the shell makes it sound, and that
prevented the shell from closing. Right, So it sounds like
he is saying he attacked. He attacked the adductor muscle,
which the clam uses to close the shell. Another thing
(21:52):
I want to note here is that I think there
could be a temptation to take a story like this
as evidence that the storyteller or the storyteller's audience would
be expected to believe that giant clams are actually dangerous,
that you know, they will come in eat your boat
or something. But I'm not sure that's actually right. In
(22:13):
this telling, the giant clam is not only a giant clam,
as in a tridacta geigis. It is a giant giant
clam described as looming over the sea like a mountain
and capable of swallowing an entire canoe. So to me,
that doesn't necessarily mean that the teller of the story
(22:34):
wanted to you to get the idea that a regular
sized giant clam poses a threat to human beings, though
that belief does appear to be common enough around the
world at different times. Maybe you can't rule it out either.
But it might well be that the clam in this
story is only understood as threatening because it is supernatural
(22:54):
and monstrous and leviathan sized, not because regular giant clams
are a threat. After all, the very next monster that
ratafights in the story is a terrible demon bird that
carried away Rada's parents and swallowed his father's head, and
this is presumably not an indication of what the storyteller
thought about the offensive capabilities of regular sea birds. So
(23:17):
I don't know that we can actually draw from this
story a belief that giant clams would hurt you. It's
just like, this is a monster giant clam. It might
be no different than when we have Knight of aleipis
a movie about monster bunnies.
Speaker 2 (23:32):
Right, if if a bunny was that big, it would
it would be a threat to us just based on
its mass, similar to you know, we know that our
housecat is not actually a threat to our life in
a direct sense, but we can certainly engage in fantasies
where it is enlarged or we are shrunken, and then
(23:52):
that changes everything. Right, if a giant clam were supernaturally
giant enough, it could it could filter feed us exactly.
Speaker 3 (24:00):
Yeah, I don't want to be filter fed or filter eaten.
Speaker 2 (24:04):
Now, why was this monster's flesh not eaten by all? Though?
That seems like a missed opportunity.
Speaker 3 (24:09):
That's a really good question. I don't know the answer.
And anybody out there listening who's a scholar of toomotu
and folklore who knows more about the Rata hero cycle, Like,
what do you have an idea? Why was the clam
not eaten like the other fish were?
Speaker 2 (24:22):
I like a story where the people eat the monster
we've encountered these sorts of stories before, and they seem
very practical. I mean, sometimes the monster's body is poisonous
by nature, and therefore, you know, it is left alone.
But I like a story where they're like, okay, let's
make use of this flesh.
Speaker 3 (24:38):
And it's not just the hero. It's actually kind of heartwarming.
The hero kills the monster and then takes it back
and it's eaten by all.
Speaker 2 (24:44):
Yeah, you know. And speaking of giant clams, I'll also
refer listeners back to our episodes on the Fata Morgana,
this being a mirage, an optical illusion that is seen
at sea, which I did get to see an example
of when I was in Indonesia. In Indonesia, but we
(25:06):
discussed the Chinese myths concerning the shin or chin, which
is a kind of giant clam, a giant giant clam,
to be sure, a supernaturally giant clam. And this one too,
kind of emerges from the water like a mountain, but
it also expels a fantastic phantasmagorical island, you know, that
throws sailors off and people sail towards it and then
(25:28):
they realize too late that this was not a real place.
At all, but just an illusion cast up by this giant,
this giant bivalve in the water. Yeah, but I don't
believe it ever, you know, latched on or ate anybody.
So I kind of skipped over it otherwise for this episode. Yeah. Now,
coming back to modern myths of giant clams eating people,
(25:53):
I want to read an excerpt from Charles Frederick Holder.
He was an American naturalist and conservations and he had
a book in eighteen eighty five title Elements of Zoology,
and this is time to understand otherwise for the time period,
a very well regarded work. So this is again not
an example of like outrageous fiction. It is not an
(26:14):
example of mythology or folklore, just you know, an attempt
to present biological facts about the natural world. And in
it he writes, quote, so powerful are they that large
sharks and rays that have accidentally crossed them have been
seized and held. That already gives us a lot to play.
(26:34):
First of all, I've crossed them, I think just means
has come close to them. I don't think this is
like a Vendetta situation he's describing here, right. He goes
on to state that the tradacna always harbors within its
shell several crabs. I actually couldn't find out out much
about this other than to say that, yeah, you will
find lots of animals living around and even among the
(26:58):
valves of a clam like this. And then he also
points out that the bisis this is the substance that
like sticks. The clam to the rock is quote so
large that it can only be cut with a hatchet.
And then he goes on to point out that eight
species are known. So still the idea that the clam
will latch on to creatures in its vicinity, including sharks
(27:22):
and rays, which, as we've discussed, are very agile creatures
that are not certain. I mean, it's one thing to
even make the claim, well that a flimsy human snorkeler
or diver might get trapped by one of these things,
but it's quite another to imagine a shark or a
ray being grabbed by something like this.
Speaker 3 (27:41):
Yeah, but that's not going to stop you from telling
a good story. I mean, so, there are lots of
perpetuators of the myth of the killer clam. In the
twentieth century, it came across many many things here that
we can discuss. One great example of the idea that
giant clams weregerous appears in a very short article that
(28:03):
was reprinted throughout, you know, the publishing world, originally in
the magazine Popular Mechanics in May nineteen twenty four. This
was volume forty one, number five. I saw a vague
reference to this in another article and I had to
go dig up the original text, and I'm glad I did,
by the way, because this entire issue of Popular Mechanics
(28:24):
is hilarious. This is sort of a digression from the clams.
But I have to discuss a few highlights from this
nineteen twenty four pop mac one headline tear gas in
police clubs to foil bandits. What The article claims that
it is impossible to remain within ten feet after the
(28:47):
gas is released. So it says, you know, you hit
the bandit with your mace or billy and it releases
the tear gas. And I was like, what about the
person hitting with it? I guess they have to be
wearing a gas.
Speaker 2 (29:00):
They just have to be gas masked up from the
get going.
Speaker 3 (29:02):
What it's in the club? That was inside the club?
Speaker 2 (29:07):
Uh.
Speaker 3 (29:07):
The other thing is the headline baking as cure for
dog ills is tried in Germany and Rob here's an
illustration for you to look at. Well, not a photo
of a guy who's got a dog, and it's just
labeled dog being baked in gas. Of Now, I have
to c it's not saying that you bake it at
(29:28):
like cooking temperatures. I think it's just like kind of
like a steam bath. It's like very warm in there.
Speaker 2 (29:33):
Like a cartoon steam bath where you would have a
cartoon character get in and only their head sticking out.
That's exactly what they're doing to this dog. That headline
really is a roller coaster because when I first read it,
I was like, oh, well, that's kind of nice. You're
baking for the dog, you're making little cookies or you know,
little treats. But no, this dude has a metal contraption
that this dog's body is stuck in.
Speaker 3 (29:56):
So this poor dog's just looking like I'm very hot.
Speaker 2 (29:59):
Yeah.
Speaker 3 (30:01):
Another one. Here's the headline. Forty pound cigar is valued
at seventy five dollars what is said to be one
of the largest cigars ever made. One of the largest
was shown at an Eastern Tobacco exposition and it goes
on to, yeah, not really say anything else except that
it's valued at seventy five dollars. It does not answer
(30:23):
the question did anybody smoke it?
Speaker 2 (30:27):
And it's so weird looking at these because my grandfather
in the I guess this is in the eighties and nineties,
he always had he had always had copies of Popular
Mechanics and Popular Science sitting around and I would look
through them as a kid, and you know, these felt
like they were accurately depicting the future. There are always
articles about, you know, new gadgets, new upcoming technologies. So
(30:51):
it's quite a trip to explore these these previous stories
in Popular Mechanics.
Speaker 3 (30:56):
Skeptical editorial standards might have been improving as the decades
went on. Maybe anyway, onto clams. So in this wacky
Popular Mechanics, there's one article titled Giant clams trap sea
divers in Grip of Shells. It's a very short article,
so I can read it in full. It says shells
(31:18):
of huge clams found off the coast of Papua often
weigh more than four hundred pounds. Divers who accidentally step
into the open lips of the monsters are not infrequently
held with such force that they cannot release themselves and
are drowned. The shells closed with such force that they
serve as gigantic traps. That's the whole article, except for
(31:41):
there's a photo of a giant clam, and we see
the characteristic shell with the with the wavy line of
the mouth, and the caption is giant clam and coral
reef off New Guinea, powerful crushing lips, partly open.
Speaker 2 (31:57):
The interesting thing here is, though it's described as partly open,
this is actually probably a situation where they're as closed
as they are going to get. Yes, And they're describing
giant clams, by the way, in exactly the area that
I was snorkling in.
Speaker 3 (32:11):
Oh that's funny.
Speaker 2 (32:12):
Now.
Speaker 3 (32:13):
The text of this popular mechanics article seems to have
been reproduced in newspapers and other publications in the nineteen twenties,
so it seems kind of like this story really got
around in the following decades, including in various bits of
pop culture. This exact clam trap scenario is depicted in
a scene from a nineteen forty eight adventure film called
(32:36):
Wake of the Red Witch starring John Wayne himself and
Gail Russell rob I put in a link for you
to look at the scene if you want. It's actually,
I don't know, it's not that remarkable as a scene,
and it's really hard to see what's going on in
the underwater photography. It's very murky. Basically, the movie is
a revenge story about this deadly feud over a woman
(32:56):
between a bitter ship captain played by John Wayne and
a wealthy shipping company owner played by Luther Adler. I
haven't seen the movie in full, but yeah, I found
a clip of this clam scene. Basically, a kid goes diving.
He accidentally sticks his leg into a tritachna clamshell. The
shell slams shut and traps him by the ankle, and
(33:17):
then John Wayne has to dive down and do battle
with the clam to get it to release the kid.
He succeeds by with the kid's foot still inside the shell.
By the way, by John Wayne, he stabs into the
gap in the clam's shell with some kind of spear
almost looks like a glave, and I was like, he's
gonna stab the foot, but the kid's okay.
Speaker 2 (33:38):
This shell in this movie, by the way, just it
looks like a giant quarium clam. You know the kind
of little clamshell that opens and closes in your standard
a quar Yeah, it's like bubbles. Yeah, it looks like
it's made out of plastic or something like plastic. And
also like no visible or at least I didn't see
any visible mantle tissue either.
Speaker 3 (33:57):
Another great example I found from popular our culture is
Superman versus giant clam. There are actually several instances of this.
The theme that is usually emphasized is like, wow, Superman
is so strong he can even pry apart the jaws
of the killer clam. That would take a mightiness born
only of his Kryptonian blood interacting with our yellow sun.
(34:22):
So the main example I came across is that Superman
fights giant clams in one arc of the Adventures of
Superman radio serial. This was a I think it was
a six episode series called The Curse of dead Man's
Island which ran from September to October nineteen forty and
in this encounter, they're on a mysterious island and Jimmy
(34:43):
Olsen and another character are swimming to shore after their
motor boat has been wrecked, and they get attacked by
a swarm of fast moving giant clams. Yeah, these clams
they not only clamp down and trap you, they actively
chase you, is what it sounds like. Don't remember the
exact wording, but it's like they're coming right for us.
Speaker 2 (35:02):
They're like wind up chattery teeth.
Speaker 3 (35:05):
Can we get a can we get a sample of
this jjuting.
Speaker 1 (35:11):
The waters clear?
Speaker 3 (35:12):
I've got to work fast before I would drown.
Speaker 1 (35:15):
Wally shells apart and fleet these things are powerful.
Speaker 3 (35:21):
Oh wow, only the Man of Steel has hands strong
enough to wrench apart the deadly molluscian grip. And I
love how you can hear Superman like grunting and groaning
and saying.
Speaker 2 (35:30):
Great Scott.
Speaker 3 (35:31):
These things are powerful. And then there are also some
some visual like Superman comics where he has to fight
a giant clam. There's one. I actually was not able
to figure out what issue this is from, so I
can't say, but I found it just like a clip
on Google image searches, where it looks like it's a
silver age Superman who's having to he gets his own
(35:52):
foot stuck in a giant clam's mouth and he has
to like shoot it with his eye lasers.
Speaker 2 (35:57):
And this is another example of the comic book giant
clam is more horizontal, yeah, positioning as opposed to vertical. Yeah,
you mentioned that film from nineteen forty eight. I ran
across another film from nineteen forty eight that also features
pretty much the same giant clam gag, and that's the
film sixteen Fathoms Deep. This one starred Lloyd Bridges as
(36:21):
well as Lawn Cheney Jr.
Speaker 3 (36:23):
This one has a lot of narration. I don't know
who's narrating, but I watched the scene you sent me,
and like, it's the exact same thing. A kid goes swimming,
clam bites his leg, somebody has to swim down and
rescue him, though it looks a lot easier this time.
The person who swims down and rescues the kid and
the clam just kind of pulls him out.
Speaker 2 (36:40):
Yeah, he just goes down and negotiates the situation. That's
right now.
Speaker 3 (36:54):
All this twentieth century killer clam stuff, when you look
into it, it's not like really claims based on anything specific.
There are claims that are supposed to be authentic, but
they're just vague generalizations. And then there's also pop culture.
But are there any actual, specific, first hand accounts of
(37:15):
giant clam attacks in the twentieth century. There's one main one,
though it will come with some major caveats. So a
lot of these stories seem to trace back to a
figure named Wilburn Dowell Cobb, an American who wrote an
article called the Pearl of a Llah in the November
(37:36):
nineteen thirty nine edition of Natural History magazine. Cobb was
at the time he wrote this article the owner of
a massive clam pearl. And I'm not fully up on
this distinction, but I know gemologists make some kind of
distinction between clam pearls and some other kind of pearls.
I'm to understand that this thing is huge enough to
(37:58):
be considered really, you know, notable and valuable, but that
generally clam pearls are not as prized as like the
iridescent kinds of pearls you might get from pearl oysters.
Speaker 2 (38:09):
Right, that's my understanding as well. The basic the composition
is different.
Speaker 3 (38:13):
Yeah, but Cob was the owner of this gigantic clam pearl.
He originally called it the Pearl of Allah. He later
renamed it the Pearl of laod Zoo. Which at the
time this article was written, this pearl was advertised as
the largest pearl ever found in nature. Cobb claimed that
(38:33):
he acquired it as a gift from a pearl diving
family in the Philippine province of Palawan in nineteen thirty four,
and so his story goes like this again. After this,
I'm going to come back with some reasons for doubting this,
but this is what he says. He says that he
was visiting a small diac fishing village on an archaeological
(38:55):
expedition with some companions. Now, I was a little confused
about the terminal he was using to refer to the
people here, because from what I understand, the term Diek
is usually used to refer to the largest ethnic group
in Borneo, not to the people of Palawan. I'm not
sure what accounts for this, but anyway, he says, one
(39:15):
night he was awakened by a great commotion and it
seemed to be a funeral. Dirge Cobb's guide explained that
his own son, who was the village chief, bog Tong,
had organized a dive to collect conk shells, which the
villagers planned to trade at market for some much needed
(39:35):
new fishing equipment. But after several dives, bog Tong realized
one of his best divers, a man named Etim, was missing.
And then here I'm going to read from Cobb's article,
he writes quote, Suspecting a giant octopus, they unsheathed their
knives and as one dove down in search of their
missing comrade. On the fourth dive, they found Etem already dead.
(40:00):
In his search for conk shells, he had failed to
see the giant tridacna clam, which was partly hidden by
coral rocks, its huge jaws held open ready to clamp
shut with the strength of a bear trap. Attim accidentally
got his hand between the shells, which snapped shut, and
thus he met his death. With the aid of ropes,
(40:22):
the men hoisted their dead comrade and his deep sea
murderer into one of their canoes.
Speaker 2 (40:28):
Deep sea murder. Again, these are generally found in coral
reef environments.
Speaker 3 (40:33):
Right, So Cobb claims that this clam, which was brought ashore,
was later revealed to contain a gigantic pearl, and it
was The pearl was first claimed by a local Muslim chieftain,
but then given to Cob as a gift after Cob
managed to save the chief's son from a deadly illness. Again,
(40:54):
this is all his own account, so there is at
least a first hand account of a giant clam snapping
down on somebody and drowning them, and the pearl itself
is actually real, but the story of where it came
from that has met with intense scrutiny from later reviewers.
(41:15):
I didn't have time to chase down all of the
different investigations of this. There have been several, but it
seems that multiple later articles point out serious reasons for
doubting the story, including the fact that Cobb changed major
details of the story over time. There was no corroborating
evidence or documentation of this from the Philippines, and Frankly,
(41:38):
while well this is just subjective and doesn't really bear
any evidential weight, I have to say just because I
noticed it myself. If you read Cobb's article, it has
a fabulous texture in the pros it reads like a
guy making up a story to make himself sound cool.
Speaker 2 (41:56):
Yeah, it sounds a little carney. It sounds very much
like someone selling the lore of the thing he is
literally selling.
Speaker 3 (42:03):
Yeah, if you want to read more, about this. There's
an article in the Atlantic called The Pearl of Laosu
by Michael LaPoint from twenty eighteen, and that gets into
the whole history of this pearl and also what happened
to it, because there was also some ownership controversy after Cobb.
Another commonly repeated claim when people are writing about this
(42:24):
idea that giant clams will attack people or clamp onto
them and trap them underwater is the claim that US
Navy diving manuals of the twentieth century portrayed the grip
of the giant clam as one of the perils of
working on the bottom. For example, there's an article that
(42:44):
I think you referred me to rob that was in
Atlas Obscura. It's about giant clams, but it's actually it's
an excerpt from a book by an author named Cynthia Barnett.
The book came out in twenty twenty two and it's
called The Sound of the Sea, Seashells and the Fate
of the Ocean. In this excerpt of the author rights quote,
the stories captured the imagination of the US Navy during
(43:06):
World War Two, when soldiers fighting in the Pacific were
briefed on the man eating clams and large sharks known
to inhabit the reefs. The man eater myth was so
persistent that decades later, navy diving manuals still advised frogmen
how to free themselves if caught in the vice like
grip of a giant clam, by inserting a knife between
(43:27):
the valves and severing the animal's a ductor muscle.
Speaker 2 (43:31):
Yeah. I ran across this tidbit and a couple other
sources I was looking at as well. But again, but
in terms of finding the original material, I couldn't couldn't
really find anything.
Speaker 3 (43:42):
Yeah, I have no reason to doubt Barnett. I'm sure
it is out there somewhere, But unfortunately I wasted a
lot of time searching in vain for the primary text here.
I was looking through navy diving manuals of the forties, fifties,
and seventies, and I never found any references to clams.
In fact, I couldn't find anything at all really about
dealing with wildlife. The sections on dealing with hazards and
(44:05):
working on the bottom are highly concerned with various forms
of entrapment underwater, But it looks to me like the
most pressing concern is what's called fouling, which is when
the diver's lifeline or air hose gets caught or tangled
on something on the bottom, like rocks or wreckage, and
(44:25):
this is very dangerous because it prevents the diver from
safely ascending. I found very little about the diver themself
being caught bodily, though in terms of threats to your
own body orientation, there are concerns about getting knocked over
or tripping and falling on a dive because in this era,
divers would wear a heavy metal helmet applied at the surface,
(44:50):
kind of like what you see in BioShock, and you
had to remain upright during a dive or you could
risk the possibility of flooding the helmet, which was very,
very bad. So for divers of this period, the real
monster you have to fear is not a creature that
lives in the sea. It's hydrostatic pressure, yeah, pressure and
(45:12):
equipment failures. That's like the main thing to worry about.
So not only did I not find any references to clams,
it just seems like wildlife is like so far down
the list of concerns, like the thing that they're really
getting into the the diver's heads here has to do
with with dealing with pressure and using your equipment properly.
Speaker 2 (45:31):
That's right, Yeah, yeah, pressure equipment issues, the threats posed
potentially by other boats if they're not aware of your presence,
things like that. Yeah, you know, to be clear, I mean,
there are various threats in the water posed by organisms,
but a certainly the giant clam doesn't really rank highly
(45:54):
among them. And I mean there's even a case to
be made this references here. I'll point outs in reef
environments and you know, when I was in reef environments
in raja Ampat, there are sharks around, but they were
not interested in us at all. So it does make
me wonder. Okay, if playing Devil's advocate, let's assume that
(46:16):
there actually was reference to this in US Navy dive
manuals of the time period. You could look at it
in one of two ways. Either, Okay, there this idea
was taken up that these organisms were potentially a threat
and therefore you needed some sort of a plan of
action should the threat arise. But maybe also a part
(46:38):
of it could have been Okay, we're training up a
lot of a lot of landsmen here to go into
the water and do things for the Navy. They're going
to have concerns about organisms in the water because they've
been watching movies or reading comic books or listening to
radio programs, and or we just have a natural aversion
to large, strange creatures in the water. Understandable. And maybe
(47:01):
part of that was like, Okay, there's no reason that
the giant clam is actually a threat. There's no reason
that even some of these sharks are necessarily a threat.
But we need to have give them a plan of
action so they'll feel more at ease in the water
knowing that there is something they can do if this,
if this event were to transpire.
Speaker 3 (47:21):
Yeah, well, you know, I wouldn't say, based on what
I was reading, that a giant clam would never be
a threat. But I would say that it doesn't appear
to me that the main threat would be that it
would close upon you. It would be that you would
It would be the same threat as like a rock
or a reef on the ground, which is fouling you
would get your lines tangled on it.
Speaker 2 (47:43):
Yeah, yeah, I would. I would agree with that, treating
it essentially like like any other large structure or rock
or piece of coral in the water.
Speaker 3 (47:54):
So beyond all this, I checked around, and from what
I can tell, the killer clam story is universally agreed
among experts a marine biologists to be without merit. There
is no solid evidence anywhere of a single example of
a person ever being killed, seriously injured, or trapped by
a tridachna lam. Marine biology resources stress again and again that,
(48:17):
like you were saying earlier, Rob, the clamshell can close defensively,
but it tends to close slowly. It has to expel
water to do so, and it has to retract its
own flesh, which tends to protrude out of the gap
in the shell. So apart from Cobb's story, which there
are serious reasons for doubting, there's no documented account anywhere
(48:40):
of a giant clam actually harming anyone.
Speaker 2 (48:42):
Yeah, you'd really have to, like Homer sense in your
arm in there, Like Sarah, you just just holding on
to the inside of the clam. You're just holding on
to the mantle tissue, and you say, yes, actually that's
what I'm doing.
Speaker 3 (48:55):
Well, yeah, I mean, I guess the other thing to
say is that it has never actually happened that we
know about in any verifiable way. Is different from saying
it couldn't happen if you did something really stupid right
like I don't know, if you like, maybe if you
really like shoved a boot down in there and you
forced it to stay inside while the clam was closing,
(49:17):
and until the clam had closed around you, it might
be hard to get it back out.
Speaker 2 (49:21):
I don't know, but that.
Speaker 3 (49:24):
We have no examples that are verifiable that this has happened.
Speaker 2 (49:29):
Don't try to be the first. I feel like you'd
really have to try. You'd really have to get in
there and really tempt fate and try to make this
happen for yourself. And you know, I guess there's one
way to go down in the history books, but surely
there's a better option. You'd have to again, essentially frame
a giant clam for murder, which I don't think is fair.
Speaker 3 (49:51):
They don't need any more trouble there. I mean, they're
having a hard time, they take a long time to grow,
they've been over harvested. Giant giant clams need a break.
Speaker 2 (50:00):
Yeah, leave them be, keep a respect respectful distance, but
by all means observe them if you get the chance.
Like I say, it was it beautiful and weird to
be in their presence. I can't stress both enough. Again,
their mantle tissue is beautiful, their size alone can be
quite a spectacle. But there is also something kind of weird,
because again we can't help but read them as analogs
(50:23):
of human physiology, and it's, you know, weird that they're
kind of like smiling up at us from the from
the seafloor.
Speaker 3 (50:32):
Smile back, yes, get out of their light.
Speaker 2 (50:37):
All right, Well, I think that's going to do it
for this episode. But of course we'd love to hear
from everyone out there. We've heard in the past from
snorkelers and divers, you know, with lots of experience. So
I know we have some snorkelers and divers out there
who have more experience with giant clams or clams in general,
and might want to chime in with their own expertise, observations,
(50:58):
or you know lore that you've heard from maybe fellow
older divers and snorkelers about giant clams, whether it's pure
mythology or fact base. We'd love to hear about you,
So write in just a reminder that stuff to Blow
Your Mind is primarily a science and culture podcast, with
core episodes on Tuesdays and Thursdays. We have short form
episodes on Wednesdays and on Fridays. We set us like
(51:19):
most serious concerns, to just talk about a weird film
on Weird House Cinema.
Speaker 3 (51:23):
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,
you can email us at contact at stuff to Blow
your Mind dot com.
Speaker 1 (51:46):
Stuff to Blow Your Mind is production of iHeartRadio. For
more podcasts from my Heart Radio, visit the iHeartRadio app,
Apple Podcasts, or wherever you listen to your favorite shows.
Welcome to Stuff to Blow Your Mind production of iHeartRadio.
Speaker 2 (00:12):
Hey you welcome to Stuff to Blow Your Mind. My
name is Robert Lamb.
Speaker 3 (00:15):
And I'm Joe McCormick.
Speaker 2 (00:17):
And in this episode, we're gonna be diving deeper on
a topic that we first explored just a little bit
on an episode of Automilia Stupendium, which of course is
one of our shorties that airs on Wednesdays, and that
is the subject of the Giant Clam. I found this
to be a fascinating topic to explore because, on one hand,
the giant clam is just an amazing organism, notable not
(00:39):
only for its size but also for its unique symbiosis.
But in addition to this, it's an organism that has
continually invited creative but highly inaccurate ideas about how they
actually behave.
Speaker 3 (00:52):
It's not hard to see why people might look at
this thing and think that it will bite you, because
it just looks like the whole thing is just a
pair of jaws like cartoon teeth.
Speaker 2 (01:03):
Yes. Yeah, And as we'll be exploring, I think the
really interesting thing here is that you see this, this idea,
this interpretation resonating not only with people who don't know
any better. Who are you know, one or multiple degrees
away from this organism and its natural habitat, but also
people in close proximity to it, or just can be
(01:24):
overwhelmed by the fact that it looks like a big mouth.
What if it was like a big mouth? And what
would the consequences of that be. The most pervasive idea,
of course, is we're talking about the idea that a
giant clam might latch onto your leg while you were
diving or snorkeling, or even in a very cartoon sense,
swallow you whole. And to be clear, just to go
(01:46):
ahead and get this out at the top, this has
never happened. There's no recorded evidence of it ever happening,
and for reasons we'll discuss, very good reasons. It pretty
much never could happen. That's right.
Speaker 3 (01:58):
There's like one real famous anecdote of a guy claiming
that it happened, and he was there and I saw
one of the babies and the baby looked at me.
There are strong reasons for thinking that this story is
not true, and other than that, it's mostly just vague
generalizations from people not citing any evidence or fictional storytelling.
Speaker 2 (02:22):
Right, right, Ben. You know that there are all sorts
of things that can go wrong in the water, and
there are lots of ways you can become injured and
so forth, but this is not really one of them.
And I think if you were gonna, if you were
going to pin your death on a giant clam, it
would be like you would have to essentially like strap
yourself to the giant clam and die drown underwater. You
(02:43):
would have to frame it in a major, insignificant way.
So yeah, in some ways, this I think is reminiscent
of our recent look at manta rays in the ways
that European sailors in particular misinterpreted the great fish as
a threat. But again, the curious thing about the myth
of the man eating clam is that while you only
find it circulating in the nineteenth and twentieth century among
Europeans and Americans, the idea also exists among native peoples,
(03:08):
who would have had more hands on understanding of what
these creatures were all about. But again, we're susceptible to
on one level, the kind of creative thinking, like you know,
this can occur separate from a logical interpretation. You know,
the idea that you know it's not a mouth, but
what if it is a mouth? And I think we'll
maybe get into a little bit about how maybe we're
(03:28):
just hardwired to see the jaws that could consume us,
even if we know those are not jaws. So yeah,
it just I think it might just boil down to
the fact that a giant clam, especially just looks too
much like a big old mouth for us to move
past it.
Speaker 3 (03:44):
And if you've never seen one of these, by the way,
you can look up a giant clam or tridacna clam
tridac na. These things have a waviness to their shells,
you know, the way the shell closes it. It is
not just a straight curved line across. It waves up
(04:04):
and down like a you know, oscillation of a sound
wave or something, which sort of suggests teeth and further
lends itself into the mouth interpretation.
Speaker 2 (04:14):
Now, speaking of mouths, it's interesting that tridacna apparently stems
from the Latin for three bites, and this goes back
to the writings of Like Plenty of the Elder and
even the Conquest of Alexander the Great, where it was
said that these could supply such meat as to require
not one, not two, but three bites for you to
consume it all. So the name actually originates in us
(04:37):
eating them, rather than any fabulous reversal on that.
Speaker 3 (04:42):
And people do eat them. By the way, A lot
of people believe the meat of this clam is a
is a delicacy. A lot of people think it's really delicious.
This has greatly harmed the clams. They are now in
a I believe, listed by the IUCN as a critically
endangered species, and there were efforts at combating this by
(05:03):
changing over some of the trade in their meat to
like farmed populations instead of wild populations, receding wild populations
and things like that. But yeah, people are definitely getting
some three bites in.
Speaker 2 (05:16):
Yeah, because they're an important part of coral reef environments,
the coral reef environments that they call home. Now, I
was excited to look into giant clams. I hadn't really
I didn't really have giant clams on my mind at all, because,
aside from maybe in the background, I had kind of
like a Looney Tunes idea of them, you know, swallowing
a diving bugs bunny or something to that effect. But
(05:36):
as I've previously mentioned on the show. Over the summer,
I had the privilege of visiting the islands of raja
Ampat in Indonesia, where rich diversity of marine life, and
this included the giant Tradacna clams, and of course the
biggest of all Tradacna geigis, and a particularly large one
in the area was known informally as Wu Tang clam.
(06:00):
And so I didn't get to dive right down to
Wu Tang clam because Wu Tang clam was like a
little deeper than some of the other than many of
the other giant clams I was seeing, but it was
still substantially large. And I included a photograph of Wu
Tang clam for you here, Joe. I'm I'm like ninety
nine percent sure this is Wu Tang clam. But this
(06:20):
is a shot from down there at its level with
proper lighting.
Speaker 3 (06:25):
Oh wow, yeah, just looking at this one image here,
it is so crusty with life all over it.
Speaker 2 (06:32):
It's hard to.
Speaker 3 (06:34):
See this as just one organism, as one clam with
its two valves, you know, slightly parted. It looks more
like a I don't know, a big piece of coral
reef for something.
Speaker 2 (06:44):
Well, that that underscores the reality here that yeah, they
are reef builders in the long term, like you know,
they settle, they grow there in one spot, and when
they eventually pass on for one reason or another, you
know they will be the bone of future coral reefs.
So yeah, that's one of the reasons they're so vitally
important to these environments.
Speaker 3 (07:06):
Another reason, I think, Rob maybe you can confirm this
because I guess you have seen them up close. I
think sometimes people might not recognize they are looking at
a giant clam, especially if they're like looking down from above,
because it's not you don't obviously see the shell. You
might just see a kind of ripply looking sheet of
(07:27):
the inner flesh of the clam, like the mantle protruding
from out of the shell. Because in a lot of
cases they will be perched somewhere in a kind of
sunlit sea bottom and they're trying to spread out and
gather sunlight on the fleshy parts. And we can talk
about the reasons for that in just a minute here.
Speaker 2 (07:45):
But you might not.
Speaker 3 (07:46):
Actually see something that looks like a clam. You might say,
what is this a big kind of flat ripple a
sea cucumber or something. Because you're just seeing the mantle.
Speaker 2 (07:55):
Right right, and the mantle tissue, it can be really
eye catching. Certainly saw this a lot with the various
giant clams that I was snorkling over. They almost feel
magical at times, seeming to pulsate with a strange energy,
and then they would as you would get near them,
they would sense you for reasons that I'll get into,
and the smaller varieties in particular would often kind of
(08:17):
like maybe not close all the way, but kind of tense. Yeah.
They were very vibrant to look at, and to your point, yeah,
they are. They are facing mouth up if you will,
because the mansle tissue needs to be, you know, have
maximum exposure to sunlight. Whereas the Looney Tunes version of
the giant clam that might eat bugs, bunny that you
(08:38):
tend to imagine it positioned less vertically and more horizontally.
Speaker 3 (08:43):
You're right, because it's like a crocodile's mouth.
Speaker 2 (08:45):
Yes. Yeah, So, as I was passing over these these clans,
the interesting thing is I still knew enough about clams
and giant clams to know that these things were not
a danger to me. They were not actually going to
try and bite me or anything to that effect. And
yet there is this undeniable resemblance to some sort of
(09:06):
a big fleshy mouth or secondary secondarily perhaps some sort
of yonic imagery. And so these associations I thought about
this fair amount as I was passing over them snorkeling, Like,
these associations connect with us, I think on a primal level,
and it's hard not to at least casually think of
(09:26):
what you're seeing in anthropomorphic terms, comparing them to basic
human physiological analogues and analogs that are like very closely
tied in to our survival and reproduction and so forth. Yeah,
mostly we're going to talk about giant clams as mouths.
But on the subject of yonic imagery, we do certainly
(09:48):
see interpretations of clamshells in general in the giant clamshell,
as well as vulva in its use as fertility emblems
as well as currency in some cultures in the past.
Sometimes you'll even see like Bodicelli's rendition of the Birth
of Venus sided in there as well, though the shell
that he depicts in that painting is a scallop shell,
(10:09):
I believe, and not actually a clamshell, but it is
presented on a scale that is more in keeping with
a giant clamshell.
Speaker 3 (10:19):
Though I think actually in that that's also bigger than
any known giant clam.
Speaker 2 (10:24):
Yeah, as we'll discuss giant clamshells, I think about the
maximum you're going to get is like four feet.
Speaker 3 (10:29):
Across, Yeah, which is very big, still very big.
Speaker 2 (10:32):
It's still enormous. But you know, they can't fit a venus. Yeah,
you couldn't fit a whole venus in there. You'd have
to really scrunch your up. Still seashells in general, you know,
pop up and Renaissance paintings, paintings sometimes with erotic suggestions
and their usage. Though quite incidentally, there is a venus
genus of clam. I was reading about this recently. Eighteenth
(10:53):
century Swedish naturalist and father of modern taxonomy, Carl Linaeus
famously described the venus claim in quite sexual terms, which
was pretty controversial at the time. Critics charged that he
quote indulged in obscene illusions. Suffice to say, it seems
quite a common interpretation, second only to the view of
(11:14):
the clam as a mouth.
Speaker 3 (11:15):
Was Linnaeus not otherwise really known for very expressive or
controversial descriptions.
Speaker 2 (11:21):
Correct. That's my understanding is that this was kind of
an outlier where suddenly everyone was like, whoa, whoa, what
are you doing? But you know, I guess the controversy
died down after a while.
Speaker 3 (11:33):
Yeah, it does seem like a biology is a funny
domain to get upset about that in.
Speaker 2 (11:39):
Yeah, yeah, all right, Well, speaking of biology, let's let's
let's go through some of the basics of the giant
clam here, particularly so again we're talking about for the
most part, we're talking about Tridacna gaigis, and it can
be found in coral reefs of the South Pacific and
Indian Oceans. They can reach sizes of up to two
(11:59):
hundred and fifty kerls are five hundred and fifty pounds,
and they can grow to somewhere over four feet or
one point two meters long or across. So again, maybe
not quite man swallowing size like we would see in
our fiction, but still incredibly big. Like they still look
like a they can still look like a massive like
(12:20):
bio chest there on the seafloor. Yeah. Now, the giant clam,
to be sure here, doesn't really have a mouth, especially
in the way, you might read it as again the
bugs bunny swallowing mouth. Instead, we have the valves, and
they are bivalves. Remember, so we have the like the
two shells that essentially howls the organism, and inside they
(12:45):
have a pair of siphons, one for drawing in food
and water and another for expelling waste. Furthermore, they are
filter feeders and they have no need for any jaw
like mechanics. There's no chewing that takes place with the
two valve. They simply close, or in the case of
the giant clams, nearly close their shells for protection. The
(13:05):
giant clams can't actually close them all the way for
a couple of reasons. And here's another big kicker. They
close their shells exceedingly slowly. One of the main predators
that they're closing their shells for protection against are sea stars,
which you are quite a threat to a number of
(13:26):
coral reef dwelling organisms. But they themselves are also slow
moving creatures. So for this very specific encounter, the closing
of the shell is actually pretty fast, but it's as
fast as it needs to be, and it's not man
catching fast.
Speaker 3 (13:42):
Yes, And the other thing you mentioned is they often
don't close their shells completely because you will still see
some of the flesh of the clam kind of protruding,
like they've got to both expel water and retract their
tissues inside in order.
Speaker 2 (13:56):
To close exactly. Now, the varied colorization of the mantle
tissues on the giant clam is due to ariticide cells
that feed light to symbiotic single celled dinoflagelet algae or zooxanthellae.
And this is where we get into the really cool
example of symbiosis going on here. The clam acquires these
(14:21):
zooxanthellae via constant filter feeding in the water, it also
acquires basic basic plectonic organisms that it actually eats, and thus,
during the day the clam is going to open wide
and extend its mantle tissue to absorb the sunlight necessary
for the algae to conduct photosynthesis, and in return, the
algae produced sugars and proteins that the clam needs to
(14:42):
survive along with its more traditional filter diet, which it
requires less off. So the giant clam has a dual
feeding strategy and this is thought to have evolved some
sixty four million years ago.
Speaker 3 (14:55):
Yeah, two different ways of eating. It is photosynthesizing with
the help of these organized that it has absorbed and
taken into itself. And then it's also filter feeding. It's
sucking through water and filtering out little bits that it
can eat.
Speaker 2 (15:08):
Yeah, and so that's that's one of the interesting like
observations you can make as you like snorkel over them.
Is like that mantle tissue is like it really seems engorged,
uh and and very out there because because it is,
it is, you know, collecting sunlight, and yeah, so fascinating
that it has this dual feeding strategy. The giant clam
(15:29):
also boasts thousands of pinhole eye spots along the mantle's
edge that allowed to detect changes in light, not only
the cycles of night and day, but also tailtale shadows
of approaching predators. And so this gets into you know,
the observation that I had as I was snorkeling over again,
the smaller of the giants, they would sometimes like tense
(15:52):
up a little bit. They wouldn't close all the way,
but there would be like a visual like rippling or
movement of the mantle tissue and even the valves. Yeah.
Speaker 3 (16:00):
Yeah, and I've seen video of the same thing happening.
If you say, you move your hand over the top
of one and cast a shadow over it, sometimes it
will kind of tense and partially close.
Speaker 2 (16:10):
Which, again the logical mind knows that, you know, it
is just responding to the presence of another organism, which
may or may not be something that is a threat
to it. But you also can't help but illogically read
it as like little mouths that are kind of going
at you, you know. So again, I think it's almost
(16:30):
impossible not to read them on additional levels as well.
Speaker 3 (16:34):
Yeah, well, I mean I think the way to think
of it is that what you're seeing there is a
retracting impulse, not a biting.
Speaker 2 (16:40):
Impulse, exactly. Yeah, it is a retracting not a biting
Because yeah, I think the other way we tend to,
you know, artificially think about them, and certainly in like
modern looney tune sense, is to think of them as
a bear trap. Yes, and we'll turn to some actual
examples from twentieth century cinema that depicts them essentially as
a bear trap just waiting down there for divers to
(17:03):
pass through it.
Speaker 3 (17:04):
Yeah, before we get to twentieth century cinema, there are
older stories of giant clams. As you know various forms
of monsters or man killers. The giant clam has appeared
(17:26):
in some myths and legends of various people's of the
Pacific Islands, sometimes as a benign creature, but sometimes as
a dangerous or monstrous creature. One interesting example I found
is in a to Amotuan version of the story of
the Polynesian hero Rata. I can't remember if Rata's come
(17:49):
up on the show before, but Rata is basically a
culture hero that you will find throughout Polynesian storytelling and
lots of different Pacific Island cultures. There are Rata stories
among the Maori, among Tahitians, to Emotuans, and others, sometimes
with a different name a slightly different name in different regions.
(18:11):
The Rata stories differ in many details, but the most
common elements are that he is a young, brave, resourceful
hero who has to go on a dangerous quest to
avenge the death of his father or to avenge some
other kind of crime against his family, and in doing
(18:32):
so he has to build a mighty canoe, which involves
felling a tree protected by spirits or magical beings of
the forest. Sometimes in older English sources these beings are
translated as elves or goblins. More recent sources, I think,
will call them things like forest spirits or something. But
(18:53):
once in this great canoe that he has made, Rada
has to go on a journey, sometimes with companions, to
avenge his family or avenge his father, and battle terrifying
monsters along the way. And so in one version of
the Rada journey, I found one of those monsters he
fights is a giant clam.
Speaker 2 (19:13):
So this is a.
Speaker 3 (19:15):
Telling of a version found among the Tuamotuan people of
the Tuamotu Islands and of Tahiti, told by a local
scholar named Taroi to a Missus Walker, and compiled into
a book called Ancient Tahiti by the British Tahitian folkloristan
scholar Tearia Henry, who lived eighteen forty seven to nineteen fifteen.
(19:37):
So I'm going to read the excerpt of the text,
and of course I have to apologize in advance for
any mispronunciations.
Speaker 2 (19:43):
I'll do my best.
Speaker 3 (19:44):
Here they were sailing on their course when the great
au or swordfish came into sight, and Rata mistook it
for land. But Tava said it was not land, but
another foe. So Rada stood prepared again for battle, and
when the monster approached the the canoe, intending to pierce it,
he killed it with his spear and presented the body
(20:05):
to the elves as before. Thus that demon was exterminated
and his flesh eaten by all. They sailed on, and
they met the great Urua, the Kavala fish, which looked
like land, but Tava told Rada it was the Kavala fish,
sent by King Puna to kill him. The fish darted
forward to carry away Rada, but he stood ready, and
(20:27):
as soon as it approached him, he thrust his spear
into its throat and killed it, and it was also
eaten by all. Next they met the great Pahua Tutahi,
a giant clam which appeared like a mountain looming up
from the sea. But Tava said, it is not land.
It is the giant clam, and Rada prepared for the
(20:47):
inevitable encounter. As his vessel was being drawn up into it.
The clam had opened its great valves and was sucking
in the waves upon which the canoe. Tua Rata was sailing.
Stood at the bow with his spear, and as soon
as they reached the center of the clam, he pierced
it through its vital part, severing its flesh from the
(21:08):
shell so that it could not close upon him. He
presented the clam to his spirit company to annihilate, and
as soon as the canoe was safely away, the dead
clam sank into the deep sea. So several interesting things
here in the story. It sounds like he's talking about
cutting the adductor muscle, which is something we see later
(21:30):
when people are talking about how to fight this clam.
In this case, it says that Rada, you know, he
stabbed it at its vital part with the spear. Severing
its flesh from the shell makes it sound, and that
prevented the shell from closing. Right, So it sounds like
he is saying he attacked. He attacked the adductor muscle,
which the clam uses to close the shell. Another thing
(21:52):
I want to note here is that I think there
could be a temptation to take a story like this
as evidence that the storyteller or the storyteller's audience would
be expected to believe that giant clams are actually dangerous,
that you know, they will come in eat your boat
or something. But I'm not sure that's actually right. In
(22:13):
this telling, the giant clam is not only a giant clam,
as in a tridacta geigis. It is a giant giant
clam described as looming over the sea like a mountain
and capable of swallowing an entire canoe. So to me,
that doesn't necessarily mean that the teller of the story
(22:34):
wanted to you to get the idea that a regular
sized giant clam poses a threat to human beings, though
that belief does appear to be common enough around the
world at different times. Maybe you can't rule it out either.
But it might well be that the clam in this
story is only understood as threatening because it is supernatural
(22:54):
and monstrous and leviathan sized, not because regular giant clams
are a threat. After all, the very next monster that
ratafights in the story is a terrible demon bird that
carried away Rada's parents and swallowed his father's head, and
this is presumably not an indication of what the storyteller
thought about the offensive capabilities of regular sea birds. So
(23:17):
I don't know that we can actually draw from this
story a belief that giant clams would hurt you. It's
just like, this is a monster giant clam. It might
be no different than when we have Knight of aleipis
a movie about monster bunnies.
Speaker 2 (23:32):
Right, if if a bunny was that big, it would
it would be a threat to us just based on
its mass, similar to you know, we know that our
housecat is not actually a threat to our life in
a direct sense, but we can certainly engage in fantasies
where it is enlarged or we are shrunken, and then
(23:52):
that changes everything. Right, if a giant clam were supernaturally
giant enough, it could it could filter feed us exactly.
Speaker 3 (24:00):
Yeah, I don't want to be filter fed or filter eaten.
Speaker 2 (24:04):
Now, why was this monster's flesh not eaten by all? Though?
That seems like a missed opportunity.
Speaker 3 (24:09):
That's a really good question. I don't know the answer.
And anybody out there listening who's a scholar of toomotu
and folklore who knows more about the Rata hero cycle, Like,
what do you have an idea? Why was the clam
not eaten like the other fish were?
Speaker 2 (24:22):
I like a story where the people eat the monster
we've encountered these sorts of stories before, and they seem
very practical. I mean, sometimes the monster's body is poisonous
by nature, and therefore, you know, it is left alone.
But I like a story where they're like, okay, let's
make use of this flesh.
Speaker 3 (24:38):
And it's not just the hero. It's actually kind of heartwarming.
The hero kills the monster and then takes it back
and it's eaten by all.
Speaker 2 (24:44):
Yeah, you know. And speaking of giant clams, I'll also
refer listeners back to our episodes on the Fata Morgana,
this being a mirage, an optical illusion that is seen
at sea, which I did get to see an example
of when I was in Indonesia. In Indonesia, but we
(25:06):
discussed the Chinese myths concerning the shin or chin, which
is a kind of giant clam, a giant giant clam,
to be sure, a supernaturally giant clam. And this one too,
kind of emerges from the water like a mountain, but
it also expels a fantastic phantasmagorical island, you know, that
throws sailors off and people sail towards it and then
(25:28):
they realize too late that this was not a real place.
At all, but just an illusion cast up by this giant,
this giant bivalve in the water. Yeah, but I don't
believe it ever, you know, latched on or ate anybody.
So I kind of skipped over it otherwise for this episode. Yeah. Now,
coming back to modern myths of giant clams eating people,
(25:53):
I want to read an excerpt from Charles Frederick Holder.
He was an American naturalist and conservations and he had
a book in eighteen eighty five title Elements of Zoology,
and this is time to understand otherwise for the time period,
a very well regarded work. So this is again not
an example of like outrageous fiction. It is not an
(26:14):
example of mythology or folklore, just you know, an attempt
to present biological facts about the natural world. And in
it he writes, quote, so powerful are they that large
sharks and rays that have accidentally crossed them have been
seized and held. That already gives us a lot to play.
(26:34):
First of all, I've crossed them, I think just means
has come close to them. I don't think this is
like a Vendetta situation he's describing here, right. He goes
on to state that the tradacna always harbors within its
shell several crabs. I actually couldn't find out out much
about this other than to say that, yeah, you will
find lots of animals living around and even among the
(26:58):
valves of a clam like this. And then he also
points out that the bisis this is the substance that
like sticks. The clam to the rock is quote so
large that it can only be cut with a hatchet.
And then he goes on to point out that eight
species are known. So still the idea that the clam
will latch on to creatures in its vicinity, including sharks
(27:22):
and rays, which, as we've discussed, are very agile creatures
that are not certain. I mean, it's one thing to
even make the claim, well that a flimsy human snorkeler
or diver might get trapped by one of these things,
but it's quite another to imagine a shark or a
ray being grabbed by something like this.
Speaker 3 (27:41):
Yeah, but that's not going to stop you from telling
a good story. I mean, so, there are lots of
perpetuators of the myth of the killer clam. In the
twentieth century, it came across many many things here that
we can discuss. One great example of the idea that
giant clams weregerous appears in a very short article that
(28:03):
was reprinted throughout, you know, the publishing world, originally in
the magazine Popular Mechanics in May nineteen twenty four. This
was volume forty one, number five. I saw a vague
reference to this in another article and I had to
go dig up the original text, and I'm glad I did,
by the way, because this entire issue of Popular Mechanics
(28:24):
is hilarious. This is sort of a digression from the clams.
But I have to discuss a few highlights from this
nineteen twenty four pop mac one headline tear gas in
police clubs to foil bandits. What The article claims that
it is impossible to remain within ten feet after the
(28:47):
gas is released. So it says, you know, you hit
the bandit with your mace or billy and it releases
the tear gas. And I was like, what about the
person hitting with it? I guess they have to be
wearing a gas.
Speaker 2 (29:00):
They just have to be gas masked up from the
get going.
Speaker 3 (29:02):
What it's in the club? That was inside the club?
Speaker 2 (29:07):
Uh.
Speaker 3 (29:07):
The other thing is the headline baking as cure for
dog ills is tried in Germany and Rob here's an
illustration for you to look at. Well, not a photo
of a guy who's got a dog, and it's just
labeled dog being baked in gas. Of Now, I have
to c it's not saying that you bake it at
(29:28):
like cooking temperatures. I think it's just like kind of
like a steam bath. It's like very warm in there.
Speaker 2 (29:33):
Like a cartoon steam bath where you would have a
cartoon character get in and only their head sticking out.
That's exactly what they're doing to this dog. That headline
really is a roller coaster because when I first read it,
I was like, oh, well, that's kind of nice. You're
baking for the dog, you're making little cookies or you know,
little treats. But no, this dude has a metal contraption
that this dog's body is stuck in.
Speaker 3 (29:56):
So this poor dog's just looking like I'm very hot.
Speaker 2 (29:59):
Yeah.
Speaker 3 (30:01):
Another one. Here's the headline. Forty pound cigar is valued
at seventy five dollars what is said to be one
of the largest cigars ever made. One of the largest
was shown at an Eastern Tobacco exposition and it goes
on to, yeah, not really say anything else except that
it's valued at seventy five dollars. It does not answer
(30:23):
the question did anybody smoke it?
Speaker 2 (30:27):
And it's so weird looking at these because my grandfather
in the I guess this is in the eighties and nineties,
he always had he had always had copies of Popular
Mechanics and Popular Science sitting around and I would look
through them as a kid, and you know, these felt
like they were accurately depicting the future. There are always
articles about, you know, new gadgets, new upcoming technologies. So
(30:51):
it's quite a trip to explore these these previous stories
in Popular Mechanics.
Speaker 3 (30:56):
Skeptical editorial standards might have been improving as the decades
went on. Maybe anyway, onto clams. So in this wacky
Popular Mechanics, there's one article titled Giant clams trap sea
divers in Grip of Shells. It's a very short article,
so I can read it in full. It says shells
(31:18):
of huge clams found off the coast of Papua often
weigh more than four hundred pounds. Divers who accidentally step
into the open lips of the monsters are not infrequently
held with such force that they cannot release themselves and
are drowned. The shells closed with such force that they
serve as gigantic traps. That's the whole article, except for
(31:41):
there's a photo of a giant clam, and we see
the characteristic shell with the with the wavy line of
the mouth, and the caption is giant clam and coral
reef off New Guinea, powerful crushing lips, partly open.
Speaker 2 (31:57):
The interesting thing here is, though it's described as partly open,
this is actually probably a situation where they're as closed
as they are going to get. Yes, And they're describing
giant clams, by the way, in exactly the area that
I was snorkling in.
Speaker 3 (32:11):
Oh that's funny.
Speaker 2 (32:12):
Now.
Speaker 3 (32:13):
The text of this popular mechanics article seems to have
been reproduced in newspapers and other publications in the nineteen twenties,
so it seems kind of like this story really got
around in the following decades, including in various bits of
pop culture. This exact clam trap scenario is depicted in
a scene from a nineteen forty eight adventure film called
(32:36):
Wake of the Red Witch starring John Wayne himself and
Gail Russell rob I put in a link for you
to look at the scene if you want. It's actually,
I don't know, it's not that remarkable as a scene,
and it's really hard to see what's going on in
the underwater photography. It's very murky. Basically, the movie is
a revenge story about this deadly feud over a woman
(32:56):
between a bitter ship captain played by John Wayne and
a wealthy shipping company owner played by Luther Adler. I
haven't seen the movie in full, but yeah, I found
a clip of this clam scene. Basically, a kid goes diving.
He accidentally sticks his leg into a tritachna clamshell. The
shell slams shut and traps him by the ankle, and
(33:17):
then John Wayne has to dive down and do battle
with the clam to get it to release the kid.
He succeeds by with the kid's foot still inside the shell.
By the way, by John Wayne, he stabs into the
gap in the clam's shell with some kind of spear
almost looks like a glave, and I was like, he's
gonna stab the foot, but the kid's okay.
Speaker 2 (33:38):
This shell in this movie, by the way, just it
looks like a giant quarium clam. You know the kind
of little clamshell that opens and closes in your standard
a quar Yeah, it's like bubbles. Yeah, it looks like
it's made out of plastic or something like plastic. And
also like no visible or at least I didn't see
any visible mantle tissue either.
Speaker 3 (33:57):
Another great example I found from popular our culture is
Superman versus giant clam. There are actually several instances of this.
The theme that is usually emphasized is like, wow, Superman
is so strong he can even pry apart the jaws
of the killer clam. That would take a mightiness born
only of his Kryptonian blood interacting with our yellow sun.
(34:22):
So the main example I came across is that Superman
fights giant clams in one arc of the Adventures of
Superman radio serial. This was a I think it was
a six episode series called The Curse of dead Man's
Island which ran from September to October nineteen forty and
in this encounter, they're on a mysterious island and Jimmy
(34:43):
Olsen and another character are swimming to shore after their
motor boat has been wrecked, and they get attacked by
a swarm of fast moving giant clams. Yeah, these clams
they not only clamp down and trap you, they actively
chase you, is what it sounds like. Don't remember the
exact wording, but it's like they're coming right for us.
Speaker 2 (35:02):
They're like wind up chattery teeth.
Speaker 3 (35:05):
Can we get a can we get a sample of
this jjuting.
Speaker 1 (35:11):
The waters clear?
Speaker 3 (35:12):
I've got to work fast before I would drown.
Speaker 1 (35:15):
Wally shells apart and fleet these things are powerful.
Speaker 3 (35:21):
Oh wow, only the Man of Steel has hands strong
enough to wrench apart the deadly molluscian grip. And I
love how you can hear Superman like grunting and groaning
and saying.
Speaker 2 (35:30):
Great Scott.
Speaker 3 (35:31):
These things are powerful. And then there are also some
some visual like Superman comics where he has to fight
a giant clam. There's one. I actually was not able
to figure out what issue this is from, so I
can't say, but I found it just like a clip
on Google image searches, where it looks like it's a
silver age Superman who's having to he gets his own
(35:52):
foot stuck in a giant clam's mouth and he has
to like shoot it with his eye lasers.
Speaker 2 (35:57):
And this is another example of the comic book giant
clam is more horizontal, yeah, positioning as opposed to vertical. Yeah,
you mentioned that film from nineteen forty eight. I ran
across another film from nineteen forty eight that also features
pretty much the same giant clam gag, and that's the
film sixteen Fathoms Deep. This one starred Lloyd Bridges as
(36:21):
well as Lawn Cheney Jr.
Speaker 3 (36:23):
This one has a lot of narration. I don't know
who's narrating, but I watched the scene you sent me,
and like, it's the exact same thing. A kid goes swimming,
clam bites his leg, somebody has to swim down and
rescue him, though it looks a lot easier this time.
The person who swims down and rescues the kid and
the clam just kind of pulls him out.
Speaker 2 (36:40):
Yeah, he just goes down and negotiates the situation. That's
right now.
Speaker 3 (36:54):
All this twentieth century killer clam stuff, when you look
into it, it's not like really claims based on anything specific.
There are claims that are supposed to be authentic, but
they're just vague generalizations. And then there's also pop culture.
But are there any actual, specific, first hand accounts of
(37:15):
giant clam attacks in the twentieth century. There's one main one,
though it will come with some major caveats. So a
lot of these stories seem to trace back to a
figure named Wilburn Dowell Cobb, an American who wrote an
article called the Pearl of a Llah in the November
(37:36):
nineteen thirty nine edition of Natural History magazine. Cobb was
at the time he wrote this article the owner of
a massive clam pearl. And I'm not fully up on
this distinction, but I know gemologists make some kind of
distinction between clam pearls and some other kind of pearls.
I'm to understand that this thing is huge enough to
(37:58):
be considered really, you know, notable and valuable, but that
generally clam pearls are not as prized as like the
iridescent kinds of pearls you might get from pearl oysters.
Speaker 2 (38:09):
Right, that's my understanding as well. The basic the composition
is different.
Speaker 3 (38:13):
Yeah, but Cob was the owner of this gigantic clam pearl.
He originally called it the Pearl of Allah. He later
renamed it the Pearl of laod Zoo. Which at the
time this article was written, this pearl was advertised as
the largest pearl ever found in nature. Cobb claimed that
(38:33):
he acquired it as a gift from a pearl diving
family in the Philippine province of Palawan in nineteen thirty four,
and so his story goes like this again. After this,
I'm going to come back with some reasons for doubting this,
but this is what he says. He says that he
was visiting a small diac fishing village on an archaeological
(38:55):
expedition with some companions. Now, I was a little confused
about the terminal he was using to refer to the
people here, because from what I understand, the term Diek
is usually used to refer to the largest ethnic group
in Borneo, not to the people of Palawan. I'm not
sure what accounts for this, but anyway, he says, one
(39:15):
night he was awakened by a great commotion and it
seemed to be a funeral. Dirge Cobb's guide explained that
his own son, who was the village chief, bog Tong,
had organized a dive to collect conk shells, which the
villagers planned to trade at market for some much needed
(39:35):
new fishing equipment. But after several dives, bog Tong realized
one of his best divers, a man named Etim, was missing.
And then here I'm going to read from Cobb's article,
he writes quote, Suspecting a giant octopus, they unsheathed their
knives and as one dove down in search of their
missing comrade. On the fourth dive, they found Etem already dead.
(40:00):
In his search for conk shells, he had failed to
see the giant tridacna clam, which was partly hidden by
coral rocks, its huge jaws held open ready to clamp
shut with the strength of a bear trap. Attim accidentally
got his hand between the shells, which snapped shut, and
thus he met his death. With the aid of ropes,
(40:22):
the men hoisted their dead comrade and his deep sea
murderer into one of their canoes.
Speaker 2 (40:28):
Deep sea murder. Again, these are generally found in coral
reef environments.
Speaker 3 (40:33):
Right, So Cobb claims that this clam, which was brought ashore,
was later revealed to contain a gigantic pearl, and it
was The pearl was first claimed by a local Muslim chieftain,
but then given to Cob as a gift after Cob
managed to save the chief's son from a deadly illness. Again,
(40:54):
this is all his own account, so there is at
least a first hand account of a giant clam snapping
down on somebody and drowning them, and the pearl itself
is actually real, but the story of where it came
from that has met with intense scrutiny from later reviewers.
(41:15):
I didn't have time to chase down all of the
different investigations of this. There have been several, but it
seems that multiple later articles point out serious reasons for
doubting the story, including the fact that Cobb changed major
details of the story over time. There was no corroborating
evidence or documentation of this from the Philippines, and Frankly,
(41:38):
while well this is just subjective and doesn't really bear
any evidential weight, I have to say just because I
noticed it myself. If you read Cobb's article, it has
a fabulous texture in the pros it reads like a
guy making up a story to make himself sound cool.
Speaker 2 (41:56):
Yeah, it sounds a little carney. It sounds very much
like someone selling the lore of the thing he is
literally selling.
Speaker 3 (42:03):
Yeah, if you want to read more, about this. There's
an article in the Atlantic called The Pearl of Laosu
by Michael LaPoint from twenty eighteen, and that gets into
the whole history of this pearl and also what happened
to it, because there was also some ownership controversy after Cobb.
Another commonly repeated claim when people are writing about this
(42:24):
idea that giant clams will attack people or clamp onto
them and trap them underwater is the claim that US
Navy diving manuals of the twentieth century portrayed the grip
of the giant clam as one of the perils of
working on the bottom. For example, there's an article that
(42:44):
I think you referred me to rob that was in
Atlas Obscura. It's about giant clams, but it's actually it's
an excerpt from a book by an author named Cynthia Barnett.
The book came out in twenty twenty two and it's
called The Sound of the Sea, Seashells and the Fate
of the Ocean. In this excerpt of the author rights quote,
the stories captured the imagination of the US Navy during
(43:06):
World War Two, when soldiers fighting in the Pacific were
briefed on the man eating clams and large sharks known
to inhabit the reefs. The man eater myth was so
persistent that decades later, navy diving manuals still advised frogmen
how to free themselves if caught in the vice like
grip of a giant clam, by inserting a knife between
(43:27):
the valves and severing the animal's a ductor muscle.
Speaker 2 (43:31):
Yeah. I ran across this tidbit and a couple other
sources I was looking at as well. But again, but
in terms of finding the original material, I couldn't couldn't
really find anything.
Speaker 3 (43:42):
Yeah, I have no reason to doubt Barnett. I'm sure
it is out there somewhere, But unfortunately I wasted a
lot of time searching in vain for the primary text here.
I was looking through navy diving manuals of the forties, fifties,
and seventies, and I never found any references to clams.
In fact, I couldn't find anything at all really about
dealing with wildlife. The sections on dealing with hazards and
(44:05):
working on the bottom are highly concerned with various forms
of entrapment underwater, But it looks to me like the
most pressing concern is what's called fouling, which is when
the diver's lifeline or air hose gets caught or tangled
on something on the bottom, like rocks or wreckage, and
(44:25):
this is very dangerous because it prevents the diver from
safely ascending. I found very little about the diver themself
being caught bodily, though in terms of threats to your
own body orientation, there are concerns about getting knocked over
or tripping and falling on a dive because in this era,
divers would wear a heavy metal helmet applied at the surface,
(44:50):
kind of like what you see in BioShock, and you
had to remain upright during a dive or you could
risk the possibility of flooding the helmet, which was very,
very bad. So for divers of this period, the real
monster you have to fear is not a creature that
lives in the sea. It's hydrostatic pressure, yeah, pressure and
(45:12):
equipment failures. That's like the main thing to worry about.
So not only did I not find any references to clams,
it just seems like wildlife is like so far down
the list of concerns, like the thing that they're really
getting into the the diver's heads here has to do
with with dealing with pressure and using your equipment properly.
Speaker 2 (45:31):
That's right, Yeah, yeah, pressure equipment issues, the threats posed
potentially by other boats if they're not aware of your presence,
things like that. Yeah, you know, to be clear, I mean,
there are various threats in the water posed by organisms,
but a certainly the giant clam doesn't really rank highly
(45:54):
among them. And I mean there's even a case to
be made this references here. I'll point outs in reef
environments and you know, when I was in reef environments
in raja Ampat, there are sharks around, but they were
not interested in us at all. So it does make
me wonder. Okay, if playing Devil's advocate, let's assume that
(46:16):
there actually was reference to this in US Navy dive
manuals of the time period. You could look at it
in one of two ways. Either, Okay, there this idea
was taken up that these organisms were potentially a threat
and therefore you needed some sort of a plan of
action should the threat arise. But maybe also a part
(46:38):
of it could have been Okay, we're training up a
lot of a lot of landsmen here to go into
the water and do things for the Navy. They're going
to have concerns about organisms in the water because they've
been watching movies or reading comic books or listening to
radio programs, and or we just have a natural aversion
to large, strange creatures in the water. Understandable. And maybe
(47:01):
part of that was like, Okay, there's no reason that
the giant clam is actually a threat. There's no reason
that even some of these sharks are necessarily a threat.
But we need to have give them a plan of
action so they'll feel more at ease in the water
knowing that there is something they can do if this,
if this event were to transpire.
Speaker 3 (47:21):
Yeah, well, you know, I wouldn't say, based on what
I was reading, that a giant clam would never be
a threat. But I would say that it doesn't appear
to me that the main threat would be that it
would close upon you. It would be that you would
It would be the same threat as like a rock
or a reef on the ground, which is fouling you
would get your lines tangled on it.
Speaker 2 (47:43):
Yeah, yeah, I would. I would agree with that, treating
it essentially like like any other large structure or rock
or piece of coral in the water.
Speaker 3 (47:54):
So beyond all this, I checked around, and from what
I can tell, the killer clam story is universally agreed
among experts a marine biologists to be without merit. There
is no solid evidence anywhere of a single example of
a person ever being killed, seriously injured, or trapped by
a tridachna lam. Marine biology resources stress again and again that,
(48:17):
like you were saying earlier, Rob, the clamshell can close defensively,
but it tends to close slowly. It has to expel
water to do so, and it has to retract its
own flesh, which tends to protrude out of the gap
in the shell. So apart from Cobb's story, which there
are serious reasons for doubting, there's no documented account anywhere
(48:40):
of a giant clam actually harming anyone.
Speaker 2 (48:42):
Yeah, you'd really have to, like Homer sense in your
arm in there, Like Sarah, you just just holding on
to the inside of the clam. You're just holding on
to the mantle tissue, and you say, yes, actually that's
what I'm doing.
Speaker 3 (48:55):
Well, yeah, I mean, I guess the other thing to
say is that it has never actually happened that we
know about in any verifiable way. Is different from saying
it couldn't happen if you did something really stupid right
like I don't know, if you like, maybe if you
really like shoved a boot down in there and you
forced it to stay inside while the clam was closing,
(49:17):
and until the clam had closed around you, it might
be hard to get it back out.
Speaker 2 (49:21):
I don't know, but that.
Speaker 3 (49:24):
We have no examples that are verifiable that this has happened.
Speaker 2 (49:29):
Don't try to be the first. I feel like you'd
really have to try. You'd really have to get in
there and really tempt fate and try to make this
happen for yourself. And you know, I guess there's one
way to go down in the history books, but surely
there's a better option. You'd have to again, essentially frame
a giant clam for murder, which I don't think is fair.
Speaker 3 (49:51):
They don't need any more trouble there. I mean, they're
having a hard time, they take a long time to grow,
they've been over harvested. Giant giant clams need a break.
Speaker 2 (50:00):
Yeah, leave them be, keep a respect respectful distance, but
by all means observe them if you get the chance.
Like I say, it was it beautiful and weird to
be in their presence. I can't stress both enough. Again,
their mantle tissue is beautiful, their size alone can be
quite a spectacle. But there is also something kind of weird,
because again we can't help but read them as analogs
(50:23):
of human physiology, and it's, you know, weird that they're
kind of like smiling up at us from the from
the seafloor.
Speaker 3 (50:32):
Smile back, yes, get out of their light.
Speaker 2 (50:37):
All right, Well, I think that's going to do it
for this episode. But of course we'd love to hear
from everyone out there. We've heard in the past from
snorkelers and divers, you know, with lots of experience. So
I know we have some snorkelers and divers out there
who have more experience with giant clams or clams in general,
and might want to chime in with their own expertise, observations,
(50:58):
or you know lore that you've heard from maybe fellow
older divers and snorkelers about giant clams, whether it's pure
mythology or fact base. We'd love to hear about you,
So write in just a reminder that stuff to Blow
Your Mind is primarily a science and culture podcast, with
core episodes on Tuesdays and Thursdays. We have short form
episodes on Wednesdays and on Fridays. We set us like
(51:19):
most serious concerns, to just talk about a weird film
on Weird House Cinema.
Speaker 3 (51:23):
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,
you can email us at contact at stuff to Blow
your Mind dot com.
Speaker 1 (51:46):
Stuff to Blow Your Mind is production of iHeartRadio. For
more podcasts from my Heart Radio, visit the iHeartRadio app,
Apple Podcasts, or wherever you listen to your favorite shows.
Stuff To Blow Your Mind News
Hosts And Creators
Robert Lamb
Joe McCormick
Popular Podcasts
Stuff You Should Know
If you've ever wanted to know about champagne, satanism, the Stonewall Uprising, chaos theory, LSD, El Nino, true crime and Rosa Parks, then look no further. Josh and Chuck have you covered.
Cardiac Cowboys
The heart was always off-limits to surgeons. Cutting into it spelled instant death for the patient. That is, until a ragtag group of doctors scattered across the Midwest and Texas decided to throw out the rule book. Working in makeshift laboratories and home garages, using medical devices made from scavenged machine parts and beer tubes, these men and women invented the field of open heart surgery. Odds are, someone you know is alive because of them. So why has history left them behind? Presented by Chris Pine, CARDIAC COWBOYS tells the gripping true story behind the birth of heart surgery, and the young, Greatest Generation doctors who made it happen. For years, they competed and feuded, racing to be the first, the best, and the most prolific. Some appeared on the cover of Time Magazine, operated on kings and advised presidents. Others ended up disgraced, penniless, and convicted of felonies. Together, they ignited a revolution in medicine, and changed the world.
The Joe Rogan Experience
The official podcast of comedian Joe Rogan.