Hunters of the Dark Ocean, Part 2

In this episode of Stuff to Blow Your Mind, Rob and Joe discuss the recent discovery of a strange new deep-water predator and highlight some of the various weird, wild and downright gnarly hunters that haunt the deepest, darkest depths of Earth’s oceans.

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Episode Transcript

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

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

Speaker 3 (00:16):
And I am Joe McCormick, and we're back with part
two in a series we are calling Hunters of the
Dark Ocean, focusing on predators that operate in deep marine
environments and folks, full disclosure if we sound like we're
broadcasting from the bottom of the sea ourselves today. I
think Rob and I are both maybe operating at lower

(00:37):
power than usual.

Speaker 4 (00:39):
I don't know. Do do you have a story here, Rob?

Speaker 2 (00:41):
Oh, just that I'm battling a cold and as of
right now, all the cold medicine is like firing at
full throttle.

Speaker 4 (00:49):
Oh nice, So we time to just right, Yeah, time.

Speaker 2 (00:52):
To just write. It may wear off halfway through and
you need a listener and get to get to appreciate
like a slightly gravelly sexier voice for me as we
discussed various slimy creatures that live in the depths.

Speaker 3 (01:05):
Yeah, so I was up a lot last night. It's
just childcare related lack of sleep.

Speaker 4 (01:13):
But hey, here we are.

Speaker 3 (01:14):
We're coming to you once again, folks. So brief recap
on part one of this series. In the last episode,
we kicked things off talking about the science news story
that originally inspired us to look at this topic of
deep ocean predators. That was a paper published last November
in the journal Systematics and Biodiversity by Weston at All

(01:37):
documenting a newly discovered genus and species of predatory crustation
which is found in the Atacama Trench in the southeastern Pacific.
The species was given the name del Sabella common chaka
the Sugary Darkness. As we talked about, and oh boy,
that really sent us down a rabbit hole of scrutinizing

(01:58):
bizarre deep sea amphib body forms.

Speaker 4 (02:01):
It was a good time. Yes.

Speaker 3 (02:03):
We also talked a bit about the general challenges facing organisms,
including predators that live in the deepest parts of the ocean,
not just pressure, darkness, and cold, but also unique resource challenges.
Since sunlight doesn't reach the bottom of the ocean, it
is generally devoid of the primary photosynthetic organisms that form

(02:24):
the base of the food chain at the surface. Instead,
the deep ocean food chain tends to build off of
a couple of things. First, chemosynthetic organisms like bacteria and
archaea that feed off of hydrogen sulfide and other compounds
from geological sources like hydrothermal vents, and then second dead

(02:44):
organic material and detritus that rains down from the sun
touched ocean above. This is sometimes called marine snow. It
includes everything from fecal matter and tiny dead organisms sinking down,
things sinking down of every ape and size. And we
also talked about the fascinating temporary ecosystems that spring up

(03:06):
around a big payload that falls from above, like a
whale carcass when it hits the bottom and the abyssle
or hatel zone.

Speaker 4 (03:14):
Yeah.

Speaker 2 (03:14):
And one of the things too that we were driving
home in that episode, and we're going to continue to
stress here and subsequent episodes, is that there is a
great deal of biodiversity in these depths, and it basically
runs opposite of what the prevailing theory was at one
point that you would just see a steady decline in

(03:36):
biodiversity down to nothing and there would just be no
life in the ocean past certain depths. And we know
that's not the case now, in part due to things
like the marine snow, the whale falls and those hydrothermal
environments as well, but also just in general, creatures that
have evolved to thrive at depths that we used to

(03:58):
think we're maybe just not possible.

Speaker 3 (04:00):
But anyway, back to recapping part one. After we talked
about those general issues and talked about the predatory amphipod,
we looked at a totally different order of oceanic predators,
known as sciphonophores, and we discussed the fascinating way that
their bodies are put together, the versions of these organisms
that are as long as a whale as thin as

(04:22):
a rail, catching prey in a sort of net made
from their own bodies. And then we discussed how, despite
most sightings of siphonophores occurring at less extreme depths, Rob
you turned up some research that included probable sightings of
predatory siphonophores at Haitel depths down within the Mariana Trench.

(04:43):
That's right, and so today we're back to discuss more.

Speaker 2 (04:46):
Now before we jump back in with the predators, though,
I want to just quickly discuss an example of a
scavenging organism in the mid depths. A polyget worm called
pobious messis, or simply the balloon worm as it's more practical,
it's more common name, because it does look like a balloon.

(05:06):
It has a small body, it's like one point five
inches or thirty six millimeters long, and it kind of
looks like I've seen it described as like a plastic bag,
like a plastic bag that is filled with fluid. It's
very translucent looking. And basically that marine snow. All of
those bits of flesh, fish poop, and other organic detritus

(05:29):
that just drifts down from the depths above. That's literally
all this thing eats. And these things are quite abundant
according to the Monterey Bay Aquarium Research Institute. They play
a key role in cycling nutrients like carbon from the
ocean's surface down into its depths. And also, no doubt
these are the prey animals for various predators in the

(05:51):
depths as well.

Speaker 3 (05:53):
Yeah, and that lines up with something we talked about
in part one, where in these deep habitats a lot
of the prey species being scavengers. So again we got this,
you know, the kind of marine debris, organic debris of
various kinds raining down from above. Then you've got the
animals that scavenge off of that dead material, and then
you've got the predators that come and eat those scavengers,

(06:17):
and then perhaps also you may have predators that eat
those predators. But certainly you have lots of predators that
eat the scavenging things, scavenging things like amphipods that we
talked about last time. So there is an animal that
I want to bring up, a deep sea predator that
I came across just kind of randomly, that I wanted
to focus on for a bit, because yes, it looks weird,

(06:39):
but it looks weird in a way that is biologically
connected to some themes we've been exploring and will continue
to explore some more. And that is an abyssle predator
known as Hypnop's mead ee or the gridi fish. So
that genus and species is spelled ip and ops and
the species is mead. I I want to give a

(07:01):
shout out to the place where I learned about this fish.
It was in a mission log hosted on THEAA Ocean
Exploration Hub from May twenty seventeen by an oceanographer named
Astroid Lightner at the time of the University of Hawaii
at Manoa. I looked her up, and I believe she's
now affiliated with Oregon State University. But in this post,

(07:24):
Lightner is talking about what she and a group of
colleagues found during one particular exploration dive in the Central
Pacific Basin, specifically a soft sedimented abyssle plane around what's
called the Clipperton Fracture Zone at a depth of about
forty four hundred meters. And just want to note that

(07:46):
the overall expedition here, so this was one dive on
a larger expedition. The overall expedition was called Mountains and
the Deep exploring the Central Pacific Basin. And one cool
connection here is that she's mentioning some of the other
scientists involved in this dive, and one of them is
a previous stuff to blow your mind guest Diva Aimon,

(08:07):
who if Yeah, if you want to check out an
interview that we did with a marine biologist who studies
the deep sea, you should look up our episode with
her in the back catalog. It's got to be well,
probably five or six years ago now. But yeah, Diva
Amon spelled Amo.

Speaker 2 (08:23):
N Oh, Yeah, she was great. The only guest we've
had on the show I think that has actually personally
been personally been down into the deep ocean.

Speaker 3 (08:32):
I remember that being a good episode. I enjoyed talking
to her. But anyway, in this post, talking about this
dive in the Pacific, Lightner is describing a survey of
organisms that these researchers did over this kind of vast,
relatively flat, sedimented patch of seafloor. Now, in the last episode,
we were talking a good bit about the Hadel zone,

(08:54):
like the deepest forty five percent or so of the
ocean by depth if you're just looking vertically. Of course,
the Haitel zone is limited to ocean trenches, so that's
a small minority of the ocean's horizontal surface. Most of
the ocean floor is not nearly that deep, and it's

(09:14):
what we would normally call the abyssal zone. That's what
we're looking at here is the abysstal zone, so not
deep deep in the trenches, but still very deep. It's
just the floor of most of the regular part of
the ocean. And talking about this abyssal plane, Lightner says
that these habitats have long been assumed to be what
she calls biologically monotonous. I interpret that to mean you

(09:36):
would expect to find roughly the same distribution of species
all across them. But then she says, you know, really
that was just sort of a guess. There were not
enough observations of these habitats to know what life forms
were there and if there were major variations in species
throughout the space. So Lightner says that during this one

(09:56):
dive that she's talking about the most abundant fishes they
found on the seafloor. Here were the fish that I
mentioned at the top of this segment, I knops Meade
or the gridye fish. This was named after a twentieth
century American ichthyologist and named it Giles Mead. And she
says that they cataloged seven of these fish during one

(10:18):
dive exploring the soft sediment, and that they're actually pretty
easy to spot because of their huge, highly reflective eyes.

Speaker 4 (10:27):
Now you might be trying to picture them in your head.

Speaker 3 (10:29):
How reflective, How easy would these things be to spot? Well, Rob,
I want you to weigh in here after looking at
a picture in the outline.

Speaker 2 (10:37):
Oh wow, yes, that's rather distinctive.

Speaker 3 (10:41):
So the fish's body is long and tubel like with
dark pigmentation. It appears to be gliding along the ocean
floor right over the top of the sediment, but on
the top of its head, So not really the front.
It's like right down on the top, it looks like
somebody has scooped out two little lima bean shaped depressions

(11:05):
in the fish's skull. And then so if you imagine
them together, like the flat sides of the lima bean
shapes are facing inward touching one another. So like put
two lima beans right next to each other with the
flat sides together, and you scoop out that volume from
the skull, and then you paint in the two scooped

(11:25):
out regions with neon yellow glow in the dark paint.
So it really does look like those toys I had
when I was a kid, a little monster where you
hold it up to the light bulb and then you
turn the light off and it glows. Looks exactly like that. Now,
this little guy might not look especially threatening given the
Lisa Frank eyes, or I don't know, maybe it does

(11:46):
look more threatening. I guess I'm sort of reminded of
some kind of movie poster. I can't remember exactly what
it is, but there's a monster that has eyes like this,
just big, you know, undifferentiated neon yellow spots. But whether
or not it looks threatening to you, this actually is
a predator eating small abyssle crustaceans. And while I think
its biology is not fully understood, it seems that these

(12:09):
bony plate like neon bean cup eyes lack a lens
and thus cannot resolve images. So it is seeing in
a way, but it's probably not seeing images. Instead, these
things are thought to only detect the presence or absence
of light. They're more like light spots, and thus are

(12:30):
probably designed by evolution to sense bioluminescence.

Speaker 4 (12:34):
From nearby prey.

Speaker 3 (12:37):
And I was thinking about this, and I think it's
just so interesting the different ways that light as just
a type of energy features throughout the trophic relationships. At
the surface where there's plenty of sunlight versus at the
bottom of the sea, light plays a role in the
food chain in both places, but those roles are so different.

(13:00):
So the surface light plays the primary energy role at
the base of the food chain. Light from the sun
powers photosynthesis and plants and other autotrophs, and that sets
off the chain of eating that goes all the way
up to the top predators. And then, in addition to
its role as the base energy input on the whole system,

(13:21):
it also provides probably the most important type of information
that fast moving animals use to survive and negotiate predation
relationships from either side of the predator prey relationship. So
whether you're a predator or a prey animal on the surface,
one of your main jobs is seeing other animals and

(13:42):
in some cases avoiding being seen. It's all an information
game based on reflected light from the sun deep at
the bottom of the ocean. It seems that light is
still a major energy input on the food chain because
of course it powers the food chain up above at
the surface, which then at some point rains down as
the marine snow or the whalefall for the scavengers at

(14:04):
the bottom of the ocean. But there is also at
the bottom of the ocean a different energy input. You
got the energy input from chemosynthetic organisms around like sea
floor vents and things, and then also down in the
abyssle or the hatel darkness. Light plays an important relationship
in this information competition between predators and prey, but it's

(14:26):
not reflected light from the sun that plays that role.
It seems to be primarily bioluminescent light and the way
that it contributes to that struggle for information advantage between
predators and prey is a bit different.

Speaker 2 (14:41):
That's right. Yeah, it is that it's not a realm
where there is no light, but the sort of like
the rules of light have changed, the importance of light
has changed. And so I guess you could look at

(15:02):
the grid eye fish here as being an example of
a case where evolution has just decided, you know, we
can scale back on the eyes a little bit. We
still need them, but we need them for just specific things.
And the next example we're going to discuss is one
that kind of goes in a different direction entirely with
the eyes. It really feels more like a scaling up

(15:25):
but also a hyper specialization of its ocular equipment.

Speaker 4 (15:31):
Tell me more.

Speaker 2 (15:33):
So, I'm going to warn you that this creature's common
name does sound a bit ridiculous, and it may earworm
you with a Beatles song. But we're talking about strawberry
squid here. Strawberry squids forever so called for their red
coloration as well as the little marks on their skin
that really do look like the seeds of a strawberry.

Speaker 4 (15:54):
Oh, they so do.

Speaker 3 (15:55):
I mean, if you zoom in on the skin of
this thing, it's uncanny how much it looks like a strawberry.

Speaker 2 (16:00):
Yeah, because sometimes you know the naming of these creatures
that it can be a bit off and just you
kind of have to squint a little bit to see
it for yourself. But here's pretty spot on. Its scientific
name is histiotouthis heteropsis, and the heteropsis gets more to
the point here as it translates to different sight or
different eye.

Speaker 4 (16:21):
Oh yes, okay, so this is the squid.

Speaker 3 (16:24):
If people have seen a picture of this before and
the thing you didn't notice about it was the strawberry
texture of the skin, you may have noticed the two
wildly different looking eyes.

Speaker 2 (16:35):
That's right, almost kind of a I'm reminded of the
whole sleep with one eye open thing, but it has
like but they're both open, but they're just different sizes
and they see in different ways. It's pretty amazing.

Speaker 4 (16:49):
It's like the christ pantocrater.

Speaker 2 (16:53):
So, according to the Monterey Bay Aquarium Research Institute, our
strawberry squid here reaches a maximum mantle length of teen
centimeters or five inches, and its habitat is the midwater
region of the twilight or mesopelagic zone, so we're talking
the upper portions of the ephotic zone, the dark ocean,
but the dark ocean. Nonetheless, However, the strawberry squid may

(17:15):
reach depths of three thy three hundred feet during the day,
but then migrates to shallower waters at night.

Speaker 3 (17:22):
Okay, and so we've talked about organisms like this before.
I mean, one great example being the sperm whale that
operates at in radically different light regimes at different parts
of of its sort of feeding cycle. Like it might
come up to shallow waters, of course, the whale would
have to come up to the surface to breathe, but
then it dives very deep into the dark in order

(17:42):
to feed. And this would be another type of organism
that goes a little bit more up into the light
zone and then down into the darker zone.

Speaker 2 (17:50):
Right right. But of course, unlike the sperm whale, and
the sperm whale does at different phases of its life
have to deal with predation. But this critter is more
like your common housecat, being both predator and prey at
all times. You know, not so much in the confines
of your house, but in the confines of the natural world.
So there are two properties that are especially revealing here

(18:12):
with this organism regarding life in the deep. First, I
want to talk about a little bit about its strawberry
coloration and as well as the seeds. So again those
are not seeds. Obviously, those little marks on its red
flesh are bioluminescent photophores. Those are light emitting organs. Now,
in general, cephalopods use photophores for different forms of camouflage

(18:37):
and antipredation, and they can pop up in various locations
on the cephalopod body plan. But for the strawberry squid
here they're on the outer skin and the purpose here
does qualify as anti predation.

Speaker 3 (18:51):
Okay, so that's kind of hard to understand because you
would think that you would think that lighting up your
body would attract predators, not repel them.

Speaker 4 (18:59):
So how does this work?

Speaker 2 (19:00):
That's right, Well, we have to remember that this is
the twilight zone. Some light does make it down this
far during the day, and if something is looking up
at you from beneath, it will see your outline against
that filtered light. If you put in like sci fi
film setting, imagine a starship, large starship powered down. It's

(19:23):
just a dark form, but it's moving against the stars,
and with a keen eye, you might notice that when
you might think, well, if you wanted to disguise your
powered down vessel, if you were to cover it with
little shiny stars, well, that might help mask your appearance.
That it might allow you to blend in to the starfield.

(19:44):
And that's sort of what's going on with the strawberry
squid here. It uses its bioluminescence to mask itself against
to blend in with the filtered down light from above
against predators below. I have a quote here that explains
this general adaptation. This is from a nineteen eighty three

(20:06):
text by Richard Edward Young titled Oceanic Bioluminescence and Overview
of General Functions. He writes, quote, this function is the
only one for which we have substantial experimental data. The
hypothesis is an old and simple one. Dahlgren nineteen sixteen
suggested that blue light from the ventral photophores and squids

(20:27):
would cause these animals in deep water to blend with
the sunlight when viewed from below. The process that allows
a mesopolagic animal to eliminate its silhouette with bioluminescence and
thereby conceal itself requires a very sophisticated mechanism. In the
animals that utilize it.

Speaker 4 (20:42):
Well.

Speaker 2 (20:43):
For maximum effectiveness, they must precisely match their luminescence to
the intensity, angular distribution, and color of the downwelling light.
For those that counter illuminate in near surface waters at night,
where the flight field is much more variable than in
deep water, the mechanism must be especially complex.

Speaker 4 (21:04):
Wow.

Speaker 3 (21:04):
So it's almost like what we see in the movie
Predator in a way where you know the predator's invisibility.
Cloak seems to be a way of kind of projecting
an image of the light patterns from behind the alien
onto the front facing side of it, so that when
you're looking at it, it's it's like a movie screen
showing you what you would expect to see if the

(21:26):
thing were not there from the from the backside. It
might not have to be that exact with with like
outlines and images in the case of the squid, but
it does need to very closely match the light intensity
and the color patterns and angular distribution of the light
that would be coming down from above otherwise.

Speaker 2 (21:45):
Yeah, So to humanize this sort of light show, it
may not be as as impressive as watching say a
cuttlefish or some other you know an or or some
sort of you know shallow water octopus blending in when
it's environment with its camouflage. But it is a complex act, nonetheless,

(22:06):
So it isn't just a matter of like, let's just
throw some stars up there on your hide so that
whatever's below can't can't make you out. Like. It's more
nuanced and it's about hitting the right light intensity at
all times. Now, that strawberry red coloration, that's a little
bit more straightforward, but it reveals another curious relationship with

(22:26):
light in the deep. This is one we've touched on
before in the past, and it is red. The color red,
maybe the color of caution. And notice on the surface,
you know, it is the color you might wear to
a wedding if you want to attract attention that sort
of thing. It is the color of it's a flashy color.
It's a sports car color, right, But in the depths

(22:48):
it's a stealth color. And that's because red light doesn't
filter this far deep, and so red organisms appear quite
black in the natural illumination i e. Not like submarine illumination,
thus further cloaking the organism here in question from predators,
but in a more passive way.

Speaker 3 (23:06):
I see, so like it's because the longer wavelengths of
visible light don't make it as deep in the water,
so the red, the more red colors just don't really
get reflected. Everything's kind of blue shifted down there.

Speaker 2 (23:17):
Yeah. But finally we have to talk about the strawberry
squid's eyes and greater depth here. It does have very
weird eyes again, different sizes, one big tubular and yellow lensed,
and this is to keep an eye out above for
the shadows of prey moving through dim waters, and then

(23:37):
there's this much smaller specialized eye to keep an eye
out below for bioluminescence of potential predators.

Speaker 3 (23:46):
So it's looking for shadows that it wants to eat
and glowing things that want to.

Speaker 2 (23:51):
Eat it, yes, exactly. And it's I mean, it's really
hard to think about this in terms of like the
human perspective, because I mean you might imagine, like, what
if I had one eye to see really well in
the day and one eye that would see really well
in the night, well sort of, And in fact, there
were older theories that that's what was going on here,

(24:12):
that this squid had two different eyes, one for when
it was at lower depths, in one when it was
a greater depths. But this would only work. This human
example would only work if you were living in the
sort of environment that this creature lives in, in which
you were on the threshold of darkness and light pretty
much at all times.

Speaker 3 (24:31):
Yeah, I mean, in a way, we do have eyes
that can function in high and low light conditions because
we have adjustable size, Like we can adjust the aperture
of the pupil, so you know, they contract and when
there's a lot of light and dilate when there's less light.

Speaker 4 (24:46):
But this is fit.

Speaker 3 (24:48):
Yeah, this is squid is in a different situation than
we are because we are almost never in a situation
where we need to be looking in one direction where
there's more light and in another direction where there's less light. Also,
we have been knock killer vision, so generally we're looking
in the same direction with both of our eyes to
get a perception of depth. Instead, the squid really has

(25:10):
eyes on the back of its head whichever way you
look from, and one way needs to be looking toward
the sky and the other eye needs to be looking away.

Speaker 2 (25:18):
Yeah. Another imperfect way of thinking about this would be
like if you had a human with one normal eye
and then one eye that was essentially blind but saw
really well into the astral plane, ever on the lookout
for astro zombies that are coming to try and kill you.
So these eyes apparently differentiate as the squid enters adulthood,

(25:38):
distorting the shape of the head to accommodate the larger
upward gazing eye. And the dimorphism is because it's a
creature again with an eye and two realms of light
at the same time. And I was reading a bit
more about this. Thompson, Robinson, and Johnson explored the creature's
asymmetric vision in a twenty seventeen paper published in Philosophical

(26:00):
Transactions with the Royal Society b. They point out that
the dim to dark mesoplagic region of the deep sea
boasts the highest diversity of visual adaptations in the sea.
A lot of evolutionary energy has to go into scraping
out a survival story in this region, dealing with bioluminescence
below and filtered sunlight above, but it is quote a

(26:22):
fertile environment for eye evolution. Now we mentioned that that
upward gazing eye has a yellow linb and they point
out that this may be used to break up the
counter illumination camouflage of their prey. They found it in
sixty five percent of the specimens that they looked at.
Yellow lenses are apparently common in upward looking deep sea

(26:44):
organisms as well, like in fish, because they're thought to
quote break counter illumination camouflage by enhancing spectral differences between
down welling sunlight and bioluminescent camouflage. So it's geared at
deciphering the very sore of counter illumination CAMO camouflage that
it itself uses.

Speaker 3 (27:04):
Mm okay, So it's like it simultaneously is wearing a
kind of lead shielding and X ray glasses.

Speaker 4 (27:12):
Yeah.

Speaker 2 (27:13):
They point out that body posture is also key. They
position themselves with their head and arms downward, with the
posterior mantle pointed upward in a vertical posture, and this
ensures that they're pointing their photophores downward again to cast
that counter illumination spell. And I think it's just such
a fascinating example of a form that has evolved to

(27:34):
thrive in a delicate environment. So their predators include various
sharks and also even whales. And as for what they
themselves prey upon, stomach contents suggest a mix of fish,
other squid as well as crustaceans strawberry squids forever.

Speaker 4 (27:49):
Let me take you.

Speaker 2 (27:50):
Down all right now. The next deep sea organism I
want to talk about is the fin deep sea octopuses
of the genus Grimpotothus, commonly referred to as Dumbo octopuses

(28:14):
because I mean, well, just look at them. Included a
couple of images here for you, Joe. They're adorable and
they boast earl like fins that remind many of Dumbo,
the flying elephant.

Speaker 3 (28:26):
They look tremendously like Dumbo. Yes, extremely cute and with
big floppy ears and almost yeah, I kind of elephantine
shape to their lumpy head body mm hmm.

Speaker 2 (28:38):
Sometimes the position of their arms also kind of reminds
one of a trunk or trunks, like it's some sort
of weird multi trunk elephant, that sort of thing. So
the Dumbo octopuses, they're members of the Serena suborder of octopods,
who are notable for having evolved away from jet propulsion
in favor of fin propulsion. So if you've ever consumed

(28:59):
any cephalopod a media, or you know, learned about them
in the past, you know that I think squid are
some of the more fabulous examples of this. They use
jet propulsion. They take they they take in a bunch
of of water and then they jet it out to
push them along through the water, often at you know,
nice high speeds.

Speaker 4 (29:20):
Well marine rockets, yeah.

Speaker 2 (29:21):
Little marine rockets. Uh. These octopods, however, have jettison back.
They also tend to lack anal flaps and ink sacs,
so they can't jet ink, which is another common self
defense mechanism of cephalopods being able to just squirt out
that cloud of ink and make a quick escape.

Speaker 4 (29:42):
Yeah, it's like the it's like the Batman, you know,
smoke escape pom. Right.

Speaker 2 (29:47):
And they also lack chromatophores, so they can't adjust their coloration.
They can't do any kind of blending in with their
environment other than what their uh, their their natural coloration
is all ready providing. Okay, their arms are web together,
which also earns them the informal name of umbrella octopuses.

Speaker 4 (30:07):
Oh well, that's just adorable.

Speaker 2 (30:09):
So what we have then, is as a bunch of
creatures that seem to have just abandoned most of like
the really expensive, evolutionarily speaking, self defense mechanisms that their
can have evolved in favor of a more just sort
of drifting, leisurely existence. Now why would that be, Well,

(30:32):
it has everything to do with how deep they actually reside.
They reside at extreme depths of at least thirteen one
hundred feet or four thousand meters, putting them squarely in
the abyssopal agic zone, so way down there, not quite
into the Hadel but still pretty turned deep like way
like in a way, we keep mentioning the Hadel zone

(30:52):
as being like, this is the extreme, this is where
the real depth happens. But no, the Hadel zone is
just that extra topping on the invert did cake here
and everything is already just crushingly deep before we reach
that threshold.

Speaker 4 (31:07):
Yeah.

Speaker 3 (31:08):
Us talking about the ocean trenches was not to suggest
that the horizontal surface of most of the bottom of
the ocean is not that deep. It is the regular
abyssle zone is deep.

Speaker 2 (31:18):
So what are the dumbo octopuses eat? Well, first of all,
they're not that big, eight to twelve inches in length,
and here in the depths they foread for pelegic invertebrates
generally close to the seafloor in the area that they're thriving,
but they don't. It's important to note they don't like
crawl around seemingly on the seafloor like like other octopods

(31:41):
are observed to do. They live, you know, in the water.
They do go down to the sea floor as well, though,
to lay their eggs, generally on deep water corals. But otherwise, yeah,
they're free swimming, dreamy floaters in the depths that have
you know, cast aside all of their evolved andry. And
it's because you know, they don't seem to have to

(32:05):
deal with that many predators. They do have predators, you know,
generally diving predators from above, but it seems that they
likely lost their various costly defense mechanisms because they thrive
in a rather depopulated region of the deep.

Speaker 3 (32:20):
Okay, And this is a type of adaptation that we've
seen in other animals and other ecosystems, where you know,
you can lose a lot of your defenses if you
just adapt so that you are able to thrive in
a difficult environment where they're not a lot of predators.

Speaker 2 (32:36):
Yeah, it reminds me in an imperfect way, I'm sure
of when I was a kid, I would look at
all these airplane illustrations and sketches, you know, and like
the er some of your higher altitude planes they often
had like really like cool looks, you know, like the
SR seventy one Blackbird or you know, various strategic bombers

(32:57):
and all. But then when you get to the U two,
which is a very very high it was you know,
a very high altitude spyplane. You know, it looks looks
a little dumb, and it just has really long wings,
but it's you know, it's it's altitude was its defense.
And in a sense, this is this is kind of
like the inversion of that, like its depth is its defense,
and therefore it doesn't need, you know, to look crazy.

(33:20):
It doesn't need to you know, have a bunch of
guns on it or in this case, you know, it's
various octopid defense mechanisms. Now, their reproductive systems also speak
to their isolation, and we see this in other organisms.
We're going to discuss another one, I think in the
next episode. If you're if you're thriving in an area
where there's just you're basically in a desert, well you're

(33:43):
you're not going to run into potential mates as much either.
I mean, you're not going to run into foes, but
you're also not going to run into potential friends. So
a female keeps multiple eggs in various states of development
inside of her body, and she can also store sperm
for extended periods of time as well, thus making the
most out of these infrequent encounters with the opposite sex. Furthermore,

(34:05):
the mother doesn't stay with the eggs once they've been laid.
According to a twenty eighteen article by Shay at All
in Current Biology, the young here hatch as fully confident juveniles,
so a newly hatched dumbo octopod can immediately begin carrying on,
feeding and so forth like any adult born.

Speaker 4 (34:27):
Ready.

Speaker 2 (34:27):
Yeah, so I love these guys. I mean they're weird looking,
They're definitely weird, But their weirdness is one of isolation
and a casting off of defensive adaptation speed ink camouflage,
because they've adapted to live so deep, not so deep
that they can't be found by predators, but seemingly such
predation is just far less common. However, it is stressed

(34:50):
in some of the literatures looking at that they do
deter predators by ballooning up. That's one thing that they
kept like they can balloon up their bodies and their
umbrella arms to appear larger than they actually are. This,
of course, is a common anti predation feature, and so
they've they've held onto that one. That's one that they
I guess it's not too costly from an evolutionary standpoint,

(35:11):
and they can keep that one for when they need it.

Speaker 3 (35:14):
But in the case of this animal, that just sounds adorable. Look,
I'm big and scary.

Speaker 2 (35:20):
Yeah, indeed, how big and scary could they? Could they
end up looking? Yeah, it seems like that's, you know,
kind of like a last ditch defense mechanism. But for
the for the most part, it's just I'm so deep,
you're probably not gonna find me. The odds are with
me that you can't find an eating all right, Where
We're gonna go ahead and close out this episode of

(35:40):
stuff to blow your mind, but we're gonna be back.
We have more to discuss in our look at dark
ocean predators, you know we have. We're gonna get back
to a creature we mentioned in passing in the first episode,
and I believe next episode is also going to be
the one where I get to discuss one of the
deep sea predators that are or if you've probably thought

(36:01):
up any like when are they going to talk about
this one? Well, the next episode is probably the episode.
In the meantime, Yeah, write in, We'd love to hear
from you. Just a reminder that Stuff to Blow Your
Mind is primarily a science and culture episode, with core
episodes on Tuesdays and Thursdays, short form episodes on Wednesdays
and on Fridays. We set aside most serious concerns to
just talk about a weird film on Weird House Cinema.

Speaker 3 (36:23):
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 stuff to Blow your
Mind dot com.

Speaker 1 (36:45):
Stuff to Blow Your Mind is production of iHeartRadio. For
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Speaker 4 (37:02):
Nations ra