Speaker 1: Welcome to Stuff to Blow Your Mind, production of iHeartRadio.
Speaker 2: Hey, welcome to you Stuff to Blow Your Mind. My
Speaker 2: name is Robert Lamb.
Speaker 3: And I am Joe McCormick, and we're back with part
Speaker 3: four in our series on predators in the deep and
Speaker 3: Dark parts of the Ocean. Now, if you're new to
Speaker 3: the show or new to the series as usual, we
Speaker 3: would recommend you go back and start with part one
Speaker 3: of the series called Hunters of the Dark Ocean Part
Speaker 3: one and listen through to catch back up and then
Speaker 3: return to meet us here once again. But also if
Speaker 3: you just want to start here, that's fine. This isn't
Speaker 3: one of those where it's absolutely crucial to take them
Speaker 3: in order. But for a brief recap of previous episodes,
Speaker 3: we talked about how the ocean can be thought of
Speaker 3: as having different environments or zones stacked vertically on one another, which,
Speaker 3: according to their depth, have different conditions. Closer to the surface,
Speaker 3: of course, there's more warmth, less pressure, more access to
Speaker 3: sunlight for phytoplankton to feast on, and thus more access
Speaker 3: to food all the way up the chain, and then
Speaker 3: as you go deeper, the waters get colder, darker, pressure,
Speaker 3: goes up, food resources become more scarce or at least
Speaker 3: less dense. And what this means is that much like
Speaker 3: how terrestrial animals are evolved to live in one type
Speaker 3: of environment and not another, marine organisms are usually adapted
Speaker 3: not just to the ocean or seawater, but to a
Speaker 3: specific zone of the ocean. So kind of like how
Speaker 3: you're not going to find jaguars living in the middle
Speaker 3: of the Sahara. You don't find the frosted flatwood salamander
Speaker 3: in the Midwest prairie. You also don't find tuna living
Speaker 3: in deep ocean trenches like eight thousand meters down. And
Speaker 3: there are some adventurous boundary crossers, but most ocean fauna
Speaker 3: are adapted to a fairly specific depth range, and the
Speaker 3: majority of those animals do live near the surface, where
Speaker 3: conditions are less extreme and resources are more plentiful. But
Speaker 3: in this series, we are interested in the creatures that
Speaker 3: can be found farther down in the darker parts of
Speaker 3: the ocean, from the sort of twilight and midnight midwaters,
Speaker 3: all the way down to the abyssal planes on the
Speaker 3: ocean floor and even further down into deep sea trenches. Specifically,
Speaker 3: we have been looking at predators in these environments now.
Speaker 3: In Part one, we talked about a recently discovered species
Speaker 3: of ghostly predatory crustacean from almost eight thousand meters down
Speaker 3: in the Atacama Trench of the Southeastern Pacific. This new
Speaker 3: species and genus was announced in a paper in November
Speaker 3: twenty twenty four, and that example sent us off examining
Speaker 3: the positively wacky body forms of crustaceans called amphipods the
Speaker 3: order to which this animal belongs, especially their deep sea varieties,
Speaker 3: some of which had major toxic jungle charisma, others were
Speaker 3: a little more like dead Dreamer in the Nightmare City,
Speaker 3: the shapes seep down from the stars, that sort of thing.
Speaker 3: We also talked about giant predatory siphonophores, extremely weird and
Speaker 3: amazing organisms that really defy our common understanding of what
Speaker 3: it means for a creature to have or be a body,
Speaker 3: and we discussed probable sightings of an unidentified predatory cephonophor
Speaker 3: in a deep ocean trench environment. In Part two, we
Speaker 3: looked at a somewhat obscure abysslefish known as the grid
Speaker 3: eye fish, which was notable to me because of its
Speaker 3: bizarre neon yellow bean shaped eye cups, and then after
Speaker 3: that we talked about a couple of cephalopods, the strawberry
Speaker 3: squid with its interesting midwater camouflage methods and a kind
Speaker 3: of bifurcated method of sight, one eye specializing in seeing
Speaker 3: shadows from above and other eye specializing in biological self
Speaker 3: illumination from below. And we also talked about oh grimpo
Speaker 3: tooth is the mbo octopus, durable little octopod who seems
Speaker 3: to have forsaken many of the biological self defense options
Speaker 3: evolved by its cephalopod kin in exchange for adapting to
Speaker 3: deeper waters where it has less pressure from its own predators.
Speaker 3: And in part three we talked about snail fishes. These
Speaker 3: are a big player, big deal in the deep ocean
Speaker 3: family of fishes that can be found in the form
Speaker 3: of many deep adapted species, including the deepest swimming fish
Speaker 3: ever convincingly documented by science, at least as of now.
Speaker 3: The deep dwelling varieties of snailfish often look like fat, slimy, pale,
Speaker 3: pink tadpoles with translucent skin. In the words of one article,
Speaker 3: we talked about guts wrapped in cellophane in my observation,
Speaker 3: kind often like a wad of sea through chewing gum
Speaker 3: with a tail, but when the angles were just right.
Speaker 3: Of course, as you pointed out, rob they can also
Speaker 3: be surprisingly cute, with kind of plaid said unassuming eye
Speaker 3: spots making them look like a creature of the hundred
Speaker 3: acre wood. Yes, yes, but one whose skin is dissolving.
Speaker 3: But despite looking either like a half dissolved a meal
Speaker 3: from RoboCop or like a cute little piglet fish, it
Speaker 3: turns out snail fishes are the top predators of many
Speaker 3: deep ocean trench environments, so they eat amphipod, scavengers and
Speaker 3: other little animal forms you find down there. They're kind
Speaker 3: of the kings and queens of the underworld. Oh and
Speaker 3: also there is good reason for suspecting there's some of
Speaker 3: the worst smelling fish on Earth. We discussed in that
Speaker 3: episode why that is likely the case.
Speaker 2: Yeah, with science, this is not just a they look smelly.
Speaker 2: In the discussion, there's actual science to back this up.
Speaker 3: After talking about snail fishes, we also looked at anglerfish,
Speaker 3: a beautiful monster of a marine predator. Actually, an anglerfish
Speaker 3: is not just one species, also a very diverse group
Speaker 3: that has a lot of different varieties, but it has
Speaker 3: its own deep adapted varieties as well. And there are
Speaker 3: so many things that make anglerfish interesting, not just how
Speaker 3: gorgeously cartoon grotesque they look, or at least in some
Speaker 3: of their forms, you know, with the jail bar teeth
Speaker 3: and the doom cute prey lure. There are also really
Speaker 3: interesting questions about their relationship with the bacteria they farm
Speaker 3: to create their glowing lure, how do they acquire these bacteria,
Speaker 3: et cetera. And also we talked about their truly amazing
Speaker 3: mating and reproduction practices, with the tiny male grafting its
Speaker 3: body onto that of the much larger female to become
Speaker 3: a kind of carry along sperm dispenser, which itself requires
Speaker 3: interesting adaptations. For example, in the anglerfish immune system, how
Speaker 3: does the anglerfish avoid rejecting the grafted male's tissue and
Speaker 3: could knowledge of this sort be used to improve outcomes
Speaker 3: for organ transplants and other related issues in human medicine. Anyway,
Speaker 3: that's all the previous episodes. Today we're back to round
Speaker 3: out the discussion of dark ocean predators with our fourth
Speaker 3: and final part.
Speaker 2: That's right now, before we jump into a full discussion
Speaker 2: on our selections. Here, I do have a quick example
Speaker 2: I want to point out because it's an extreme example
Speaker 2: of something we discussed previously. The advantage in the deep
Speaker 2: water is in the dark ocean of having an oversized
Speaker 2: stomach that allows you to consume all you can eat
Speaker 2: when a rare meal presents itself. And this brings us
Speaker 2: to the black swallower. This is the rare fish that
Speaker 2: can swallow a fish bigger than itself via distensable stomach.
Speaker 4: You might be.
Speaker 2: Tempted to imagine like a fish with a like a
Speaker 2: beer belly that is not severe enough for what can
Speaker 2: occur here. Joe I included an illustration in a photo here,
Speaker 2: and I encourage everyone out there, when it's safe to
Speaker 2: do so, look up, look up some images of the
Speaker 2: black swallow or fish, and it is. It's pretty amazing.
Speaker 2: So essentially, it has a stomach the balloons up enough
Speaker 2: to contain a fish twice its own length and ten
Speaker 2: times its own mass.
Speaker 3: It looks like a sardine with like a small mattress
Speaker 3: folded up on its stomach.
Speaker 2: If this were not actually real, it would seem grotesque
Speaker 2: enough that it had to be, you know, something out
Speaker 2: of the human imagination. It's just it looks bizarre, just
Speaker 2: this stomach stuffed with an oversized fish, a fish larger
Speaker 2: than itself. And there are various discussions in the literature
Speaker 2: of like how does it actually eat the fish? How
Speaker 2: does it like walk its jaws up the body of
Speaker 2: the fish that it is consumed.
Speaker 3: It is true, it's hard to understand how what you're
Speaker 3: looking at is real, especially and you shared a couple
Speaker 3: of images rob one is like an illustration, but the
Speaker 3: other is like a photo.
Speaker 4: Of I think.
Speaker 3: I guess one of these ate something a little too
Speaker 3: big for its own good, and it's like a much
Speaker 3: larger fish inside the smaller fish's belly. I don't understand
Speaker 3: how it got that in there, but.
Speaker 2: You are right, it is possible for these fish to
Speaker 2: eat something that's too big. And here's the crazy detail
Speaker 2: on all of that. Apparently most of the specimens of
Speaker 2: black swallower that scientists have studied, they've made their way
Speaker 2: to the surface because the fish in question apparently ate
Speaker 2: another fish too big for it to digest before decomposition
Speaker 2: set in on their meal. So, in other words, they're
Speaker 2: two large meals rotted in their giant gut before their
Speaker 2: stomach could break it down, resulting in all those decomposition
Speaker 2: gases turning the fish into a surface bound rock balloon,
Speaker 2: which just takes them out of their deep water habitat
Speaker 2: right up to the surface, killing them.
Speaker 4: Yeah. You don't want that.
Speaker 2: Yeah, So I just had to bring this one up
Speaker 2: because the deep ocean, as we discussed it, is a
Speaker 2: place sometimes of extremes, and here is an extreme example
Speaker 2: via deep water evolution of an oversized stomach to allow
Speaker 2: these individuals to eat all they can when a meal
Speaker 2: presents itself.
Speaker 3: Now, I do have a particular deep sea predatory species
Speaker 3: that I briefly want to talk about later in this episode,
Speaker 3: but before we get to that, there was something that
Speaker 3: I found really interesting, a sort of research trail I
Speaker 3: went down that I'd like to mention, and that is
Speaker 3: on the question is it just us or do fish
Speaker 3: actually get measurably.
Speaker 4: Weirder in deeper water?
Speaker 3: And I think the answer is it's not just us
Speaker 3: if you define weird as possessing more unusual and diverse
Speaker 3: body shapes. Yes, there is research suggesting that fish in deeper,
Speaker 3: darker waters tend to have more diverse distributions of body
Speaker 3: forms in other words, they're undergoing more wildly experimental evolutionary
Speaker 3: pathways than the fish in shallower, more abundant waters. Where
Speaker 3: it's not that there's no diversity. There is diversity in
Speaker 3: shallower waters, but you'll find a lot more fish there,
Speaker 3: all doing the same thing with their bodies.
Speaker 2: Whereas in the deep they're getting weirder, or in the
Speaker 2: words of David Lynch, they're becoming more pure.
Speaker 3: So this is according to a paper I was reading
Speaker 3: published in twenty twenty one in the journal Ecology Letters
Speaker 3: by Martinez at All, called the deep sea is a
Speaker 3: hot spot of fish body shape evolution, and in their abstract,
Speaker 3: the authors introduce this idea by writing, quote, deep sea
Speaker 3: fishes have long captured our imagination with striking adaptations to
Speaker 3: life in the mysterious abyss, raising the possibility that this cold,
Speaker 3: dark ocean region may be a key hub for physiological
Speaker 3: and functional diversification. We explore this idea through an analysis
Speaker 3: of body shape evolution across ocean depth zones in over
Speaker 3: three thousand species of marine teleost fishes. So what did
Speaker 3: the survey yield? Well, yes, the authors found that quote
Speaker 3: morphological disparity of marine fish body plants incrementally increases nearly
Speaker 3: two fold from ocean surface layers to the deep sea. Now,
Speaker 3: how do you measure morphological disparity that variable they're looking
Speaker 3: at there, Well, they looked at all these different species
Speaker 3: of fish, thousands of different species from different parts of
Speaker 3: the ocean, and they compared a bunch of different measures,
Speaker 3: so basic body dimensions, length, depth and width, jaw size,
Speaker 3: head size, size of what's called the caudal peduncle basically
Speaker 3: the fleshy, tapering heart of the fish leading to the
Speaker 3: tail fin kind of the bridge to the tail. And
Speaker 3: they used these measurements to create a sort of graph
Speaker 3: or morpho space for the fish found in each zone.
Speaker 3: And what they found was that in shallower waters, while
Speaker 3: there is plenty of diversity, the body forms of different
Speaker 3: fish species tend on average to be more clustered around
Speaker 3: a standard kind of optimized design. There's just a lot
Speaker 3: more sameness.
Speaker 4: Quote.
Speaker 3: Fishes in the shallow depth zone had a large overall
Speaker 3: range in body shapes, but a majority of these species
Speaker 3: were found in high density within a small region of
Speaker 3: the morphospace. These species were centered on a fusiform or
Speaker 3: spindle shaped body typified by snappers or Lutianity and Raba
Speaker 3: included a picture of a snapper for you to look
Speaker 3: at in the outline here. So this is going to
Speaker 3: be the basic body shape of the on average optimized
Speaker 3: shallow water fish. There's gonna be just a a ton
Speaker 3: of fish that are shaped basically like this.
Speaker 2: Yeah, it's a good body shape. They're not gonna shame
Speaker 2: this fish. The fish looks good, but it is very
Speaker 2: identifiable as a fish. This fish photo could be on
Speaker 2: the Wikipedia page for fish.
Speaker 4: Yeah.
Speaker 3: Yeah, yeah, it's not gonna freak anybody out. This is
Speaker 3: not suggesting deep, strange or again, in Lynch's words, purity. However,
Speaker 3: in the intermediate depth zone, so you go down below
Speaker 3: the surface area, while this body shape is still sort
Speaker 3: of found, this fusiform body shape, there is a good
Speaker 3: bit more diversity. Body forms are less clustered around this
Speaker 3: common design and more spread out on the morphospace graph.
Speaker 3: And interestingly, quote, it is at these intermediate depths that
Speaker 3: a body plan almost nonexistent in shallow waters begins to appear,
Speaker 3: and that is quote species with elongated and tapered tails.
Speaker 3: So it's interesting we've mentioned a couple of abyssle and
Speaker 3: hatelfish fish in the deepest deepest parts of the ocean,
Speaker 3: the Abyssle plains and then even deeper than the Hatele
Speaker 3: zone in the trenches, and both of these fish species
Speaker 3: tended to have something like this design they're mentioning here,
Speaker 3: elongated bodies with tapering tails. Kind of interesting. Finally, in
Speaker 3: the deepest part of the sea, the authors found the
Speaker 3: greatest diversity of body forms mapped on the morphospace, especially
Speaker 3: landing in extremes along the axis of body elongation.
Speaker 4: Quote.
Speaker 3: At one extreme are the most slender species in our
Speaker 3: data set, snipe eels, more on that in the second,
Speaker 3: and at the other are globe shaped species like oceanic
Speaker 3: angler fishes. Now, the snipe eel, that's also worth a
Speaker 3: lookup if you get a chance. It looks like a
Speaker 3: gray whip with cartoon duck lips. So at the other
Speaker 3: end of the axis, you know, we've already talked about
Speaker 3: like the very blob shaped deep ocean angler fishes, and
Speaker 3: there are more blob shaped fish you find in the
Speaker 3: deep deep water. But you also get this other extreme,
Speaker 3: the fish that are so long and thin they're like
Speaker 3: a string almost, and yet they are still fish.
Speaker 2: This is the most Pixar already fish I think I've
Speaker 2: ever seen. You can imagine just an image of this
Speaker 2: fish going out to casting directors and just saying, find
Speaker 2: me a voice for this fish. It has a lot
Speaker 2: of character.
Speaker 4: Hey, they call me slam.
Speaker 2: You know. Yeah, yeah, I can see that working. I
Speaker 2: was imagine like Emo Phillips would be good. Oh he
Speaker 2: may already play a fish and Pixar maybe maybe he's
Speaker 2: already taken.
Speaker 4: Yeah.
Speaker 3: So to make these deep evolved fish, often it seems
Speaker 3: like you could start with a snapper fish and then
Speaker 3: you either squash it into a wad you kind of
Speaker 3: bulldog scullet it, or you stretch it out into a noodle,
Speaker 3: so you've got like whips and blobs. The authors say
Speaker 3: that also in the deepest zone, you tend to find
Speaker 3: fishes with huge mouths relative to their bodies. Big mouths
Speaker 3: and strangely tapered tails like we saw with the snail fish,
Speaker 3: so it looks like a tadpole, you know, instead of
Speaker 3: spreading out like most fishtails you think of, it just
Speaker 3: kind of tapers off to a little pencil tail. So
Speaker 3: there is a huge difference here, essentially double the evolution
Speaker 3: of disparate fish body forms in the deep zone compared
Speaker 3: to the near surface zone, where you just see a
Speaker 3: lot more species with similar body forms. What explains this well,
Speaker 3: The authors have some ideas, and those ideas come back
Speaker 3: to something we've touched on already in earlier parts of
Speaker 3: this series, the interaction between light conditions and predation. So
Speaker 3: in the photic zone of the ocean, where sunlight penetrates
Speaker 3: the water, the authors talk about how there is a
Speaker 3: lot of hunting by sight. Predators can see prey and
Speaker 3: vice versa. Pray can see predators at a relatively long distance.
Speaker 3: So there is predator and prey, you know, awareness of
Speaker 3: each other with significant distance in between. And it seems
Speaker 3: like when predators and prey can see each other at
Speaker 3: a distance, it gives rise to these kind of recurring
Speaker 3: predation patterns, things like stalking and chasing. Survival often becomes
Speaker 3: a literal race, where like swimming speed and maneuverability are
Speaker 3: the key factors that determine whether you live or die.
Speaker 3: So there's an arms race based around swimming speed. And
Speaker 3: I don't know if this is a good analogy. The
Speaker 3: authors don't make it themselves, but it also made me
Speaker 3: think about how it seems to me that there is
Speaker 3: a lot of evolutionary pressure for like quadrupedal mammals to
Speaker 3: specialized for speed when they live in very open environment,
Speaker 3: something of like the savannah right right where you sightlines
Speaker 3: are long. So the snapper form that we talked about
Speaker 3: that is so common in shallower waters maybe just kind
Speaker 3: of an optimized evolutionary design for the light drenched environment
Speaker 3: that leads to this arms race on swimming and the
Speaker 3: authors so that's one part of it, the main predation
Speaker 3: interactions predator prey interactions based on light. Also, though they
Speaker 3: point out that shallow water fish face physical environmental pressures
Speaker 3: that deep water fish usually do not face, and there
Speaker 3: are actually a lot of different things to consider here.
Speaker 3: So near the surface, you're going to have like surface
Speaker 3: weather effects and turbulent waters and more variable current that
Speaker 3: you might need to fight against, fighting against unpredictably flowing water.
Speaker 3: And also if fish live in coastal environments or along
Speaker 3: rocky seafloors, they might be needing to have ways of
Speaker 3: dealing with those environments, like rocky bottoms or reefs, maybe
Speaker 3: ways of hiding and getting around in those places. Those
Speaker 3: just create all different kinds of new evolutionary pressures. The
Speaker 3: conditions in the deep ocean, on the other hand, are
Speaker 3: relatively stable. You're not going to be fighting with a
Speaker 3: lot of weather or current or you know, like there's
Speaker 3: not a lot of different stuff going on. There's going
Speaker 3: to be a lot of floating or sitting and scuttling
Speaker 3: around along the kind of sedimented bottom.
Speaker 2: Yeah, which is We touched briefly on this with the siphonophores,
Speaker 2: mentioning that like some of the siphonophores are rather delicate
Speaker 2: in their their body structure, but they're in an area
Speaker 2: where they're not having to deal with currents and so forth,
Speaker 2: they can just live free and weird like that exactly.
Speaker 3: But also coming back to the thing about light allowing
Speaker 3: predators and prey to see one another at a distance
Speaker 3: and putting this pressure on chasing and maneuvering, the authors
Speaker 3: say that, you know, in the deepest parts of the ocean,
Speaker 3: it's kind of like the information horizon of death or
Speaker 3: of getting.
Speaker 4: A meal is much shorter.
Speaker 3: Like fish and prey, the predators in prey don't see
Speaker 3: each other at a distance. They're much more likely to
Speaker 3: just kind of bump into each other quite suddenly. Predation
Speaker 3: happens quickly in close quarters. And that's kind of interesting
Speaker 3: because it seems that this change in light conditions and
Speaker 3: the relatively short information horizon on which you can detect
Speaker 3: the presence of a predator or prey animal, it kind
Speaker 3: of relieves the otherwise overwhelming evolutionary pressure on swimming power
Speaker 3: like speed and maneuverability, and it allows deep adapted species
Speaker 3: to run weird experiments in survival, for example, by favoring
Speaker 3: body types that swim relatively slowly but can serve metabolic
Speaker 3: energy or specialize in surviving in extremely high pressure and
Speaker 3: low temperature environments. And the authors point out that this
Speaker 3: explanation is supported by the observation that many deep dwelling
Speaker 3: species of fish have kind of weak muscles. They have
Speaker 3: like low density or what are called watery muscles, which
Speaker 3: does probably make them weaker or slower swimmers, but it
Speaker 3: also helps in other ways. It helps them maintain neutral buoyancy,
Speaker 3: so that's the ability to neither float up nor sink,
Speaker 3: just kind of sit right where you are in the
Speaker 3: water column. They also point out that the extreme hydrostatic
Speaker 3: pressure of the deep ocean may actually make efficient swimming easier.
Speaker 3: Quote in laboratory settings. European eels experienced approximately sixty percent
Speaker 3: lower cost of transport under high pressure conditions. Elevated rates
Speaker 3: of evolution for locomotor traits in the deep ocean may
Speaker 3: therefore reflect the relaxation of strong selection for some aspects
Speaker 3: of locomotive performance, such as maneuverability and high speed cruising.
Speaker 3: So I thought this was interesting because it seems like, ironically,
Speaker 3: these extreme conditions in the deep ocean allow for more
Speaker 3: biological diversity and less grouping around these body shapes that
Speaker 3: get used over and over. It's sort of the opposite
Speaker 3: of what you would think. You would kind of think
Speaker 3: that the extreme environments would tend to force a lot
Speaker 3: of like a much narrower range of what could survive there,
Speaker 3: and instead it proves to be a kind of experiment
Speaker 3: kind of free experimentation space for evolution. And so that's interesting.
Speaker 3: Maybe I want to come back to that in a minute.
Speaker 3: But there are also it's worth pointing out there are
Speaker 3: a few things about the deep ocean that might be
Speaker 3: thought of as analogous to the pressure on swimming speed
Speaker 3: and maneuverability in the shallow ocean. One thing is the
Speaker 3: overwhelming pressure to not miss out on a chance to eat,
Speaker 3: and that leads to one thing that they found, a
Speaker 3: thing that's not variable. Among deep sea fishes, they almost
Speaker 3: all seem to have big mouths, specifically long jaws. This
Speaker 3: goes back to your black swallower example. In that example,
Speaker 3: it was the stomach, though I suspect it probably also
Speaker 3: has relatively large jaws compared to fish of its size
Speaker 3: throughout the ocean. But the thinking here is that the
Speaker 3: big mouths, the long jaws is about resource scarcity, kind
Speaker 3: of like the big stomachs the author's right quote befitting
Speaker 3: rare encounters with sparsely distributed prey. So it's like when
Speaker 3: you come across food, you just do not want to
Speaker 3: miss the chance because you're already full, or because you
Speaker 3: can't fit the prey in your mouth, or because maybe
Speaker 3: you bite it but you don't have a good grip
Speaker 3: and it gets away. You just want to make sure
Speaker 3: that when you come in contact with the scarce spit
Speaker 3: of food, you are keeping it and you can digest it.
Speaker 2: Yes, and this is definitely the case with angler fish
Speaker 2: that we talked about in the last episode. Yeah, big mouths,
Speaker 2: big stomachs, you don't want to have to turn down
Speaker 2: a meal because you don't have room. There's plenty of room,
Speaker 2: there's room to get in, and there's room to digest.
Speaker 3: One more thing I was looking into is I was
Speaker 3: trying to check out research on why you find these
Speaker 3: more elongated body forms and fishes, like not just why
Speaker 3: there's more safety to experiment with that kind of body form,
Speaker 3: but actually, like what is the advantage in the deep ocean.
Speaker 3: And it seems like maybe long slender body forms make
Speaker 3: swimming more energetically efficient. You can swim while expending less
Speaker 3: energy when you're kind of elongated like that. And also
Speaker 3: I did come across one study proposing that elongated or
Speaker 3: tapering body forms make it easier to swim backwards, which
Speaker 3: I thought was of interesting, saying that if you have
Speaker 3: an elongated body form like some of these fish, it's
Speaker 3: easier to suddenly reverse direction and go back in exactly.
Speaker 4: The way you came.
Speaker 2: Hmm. Interesting.
Speaker 3: But anyway, coming back to general thoughts on this idea
Speaker 3: that these more extreme deep ocean environments allow for more
Speaker 3: evolutionary diversity, One thing is that this dynamic does seem
Speaker 3: to be specific to physical facts about the different things
Speaker 3: about the ocean, like the light actually does influence influence
Speaker 3: the predator prey interactions that force the well lit areas
Speaker 3: to specialize for speed and maneuverability. So that is one
Speaker 3: thing that's kind of specific to the ocean, but in
Speaker 3: the more general sense, it makes me wonder if we
Speaker 3: have a tendency to think about plentiful, abundant, easy living
Speaker 3: environ min's the wrong way, you know, Like when an
Speaker 3: environment has a lot of food and opportunity and it's
Speaker 3: easier to live in, it makes you think that that's
Speaker 3: where life can thrive more easily, and thus can you know,
Speaker 3: can be anything, can it can experiment evolutionarily. But in fact,
Speaker 3: it seems that part of what's going on in the
Speaker 3: easier to live in environments is a lot of things
Speaker 3: want to live there, so there's a lot of competition.
Speaker 3: So it's putting a lot of pressure on the things
Speaker 3: that do live there to you know, make it really count.
Speaker 3: So they have to optimize and they like, you can't
Speaker 3: be just a little bit slower than the other fish,
Speaker 3: so you've all got to be these fast swimming fish.
Speaker 3: So there's actually less room for evolutionary diversity.
Speaker 2: There's probably some sort of perfect business world example of this.
Speaker 2: But the only thing coming to my mind is like, oh,
Speaker 2: if you open a bar in the city, you almost
Speaker 2: have to have a television screen to play the sports
Speaker 2: on another because that's just what everyone expects and that's
Speaker 2: what all the other bars have. Yeah, like I said,
Speaker 2: there's probably a better analogy than that.
Speaker 4: I don't think.
Speaker 3: Yeah, I don't think this to whatever extent this is
Speaker 3: true about nature, I don't think it is necessarily a
Speaker 3: good metaphor for other types of competition. And you know,
Speaker 3: evolutionary environments you might think of, like with ideas or
Speaker 3: businesses or anything like that, but there might be some
Speaker 3: ways in which that applies.
Speaker 2: Business headed folks. Get back to us.
Speaker 3: Let us know now, Rob, I know today you wanted
Speaker 3: to talk about something else having to do with light
Speaker 3: conditions in the different zones of the ocean, specifically bioluminescence,
Speaker 3: and I want to get to that, but just briefly
Speaker 3: before we do that, I want to mention one more
Speaker 3: interesting fish I came across, and that is another predatory
Speaker 3: abyssle fish known as Bathipterois gralitour, commonly known as the
Speaker 3: tripod fish. Though this is a little confusing because the
Speaker 3: word tripodfish is also used to refer to more generally
Speaker 3: a bunch of fish in this family, but sometimes this
Speaker 3: species of fish in particular is called the tripod fish.
Speaker 3: These are also sometimes known as spiderfish or the tripod spiderfish.
Speaker 3: I actually first came across this because of its taxonomic
Speaker 3: relation to the grideye fish that we talked about in
Speaker 3: Part two. The tripod fish is also part of that
Speaker 3: fish's family, the family ibnopidy.
Speaker 4: Now, this fish.
Speaker 3: Does not have neon yellow bean cup eyes, but like
Speaker 3: the grideye fish, it is a bottom dwelling predator that
Speaker 3: can be found in the abyssle planes of the deep ocean,
Speaker 3: so not quite as deep swimming as like the trench
Speaker 3: snailfish that we talked about in the last episode, but
Speaker 3: still one of the deepest fish species.
Speaker 4: In the world.
Speaker 3: And the really amazing adaptation that makes this species sort
Speaker 3: of famous is the way that it appears to stand
Speaker 3: on stilts off the ocean floor, three of them, two
Speaker 3: projecting out of the fish's flanks from its lower fins
Speaker 3: on the side, and the third projecting out behind the
Speaker 3: fish from the bottom of its tail fin, making this
Speaker 3: fish kind of the equivalent of like the Martian tripods
Speaker 3: and War of the Worlds. It's standing up on three legs,
Speaker 3: towering over the other things that might crawl along the
Speaker 3: ocean floor. The tripod fish is commonly known as a
Speaker 3: demersal fish, meaning a fish that lives on or directly
Speaker 3: above the bottom substrate of a lake or sea. And
Speaker 3: there are organisms that you'll see gliding directly over the sediment.
Speaker 3: But what I like about the tripod fish is that
Speaker 3: it looks like it almost daintily does not want to
Speaker 3: sully its fins in the mud, and it uses these
Speaker 3: biological stilts to stand a few of its body lengths
Speaker 3: up above the bottom. For a formal description of the species,
Speaker 3: I dug up a report published in the journal Pacific
Speaker 3: Science from nineteen ninety by a pair of researchers named
Speaker 3: Anthony T.
Speaker 4: Jones and Kenneth J. Sulak.
Speaker 3: This paper was describing observations of tripod fish from a
Speaker 3: submersible dive off the coast of Hawaii at depths of
Speaker 3: greater than one thousand meters, and, in the author's words quote,
Speaker 3: the fish were photographed on the fine rippled sediment at
Speaker 3: depths between eleven hundred and forty and thirteen hundred and
Speaker 3: twenty meters on the southern slope of Maui. The specimens
Speaker 3: were identified by the features that characterize the species, very
Speaker 3: long produced pelvic and caudal fin rays, a uniformly dark body,
Speaker 3: an unpigmented dorsal fin, an undivided pectoral fin held upright
Speaker 3: with the rays extended straight, and lower caudal fin base
Speaker 3: canted anteriorly. So tripod fish are predators that sit up
Speaker 3: on their stilt legs facing into the current, waiting for
Speaker 3: prey to come near them. And there's something very interesting
Speaker 3: about these ste because when you see them standing up
Speaker 3: on the stilts, and it kind of suggests that these
Speaker 3: stilts are I don't know that they're stiff, like they
Speaker 3: look like they would have to be in order to
Speaker 3: support your weight like that, like the legs of a stool.
Speaker 3: But an interesting thing that Jones and Sulac note is
Speaker 3: that while these rays, these things appear stiff, when the
Speaker 3: fish is standing up off the bottom, suddenly the fish
Speaker 3: will get disturbed. Maybe it'll get kind of disturbed by
Speaker 3: like the arm of the of the remote vehicle, and
Speaker 3: it'll suddenly swim away. And then these things like lose
Speaker 3: their their rigidity and they become flexible. They just appear
Speaker 3: to glide behind the fish. So it's kind of interesting
Speaker 3: imagining how they do that. Maybe some sort of internal
Speaker 3: fluid pressure mechanism or something, but interesting to wonder how
Speaker 3: But instead of relying on site to catch pray, like
Speaker 3: we were just talking about, the tripod fish seem to
Speaker 3: rely on sensitive elongated pectoral fin rays. Look up pictures
Speaker 3: of these things. They will be perching on the bottom
Speaker 3: on the three legs, and then they'll have what looks
Speaker 3: like two little antennae coming up off of their heads
Speaker 3: like or like devil horns, and you can see these
Speaker 3: devil horns poking up into the water like they're kind
Speaker 3: of feeling around in the water for something. And it
Speaker 3: seems that is what they're doing. They're detecting prey animals
Speaker 3: drifting along with mechanical and perhaps gustatory sensations, and then
Speaker 3: these these fins help guide the prey to the mouth.
Speaker 2: Oh wow, Yes, I definitely encourage everyone to look up
Speaker 2: images of these fish, because yeah, you have those the
Speaker 2: tripod configuration on the bottom, but then you have those
Speaker 2: two those two additional elongated quote unquote antennae those it
Speaker 2: almost looks like it's intended for it to like walk
Speaker 2: another way, like it's like it's kind of got it's
Speaker 2: reaching up for a ceiling that isn't there in the
Speaker 2: same way that it's reach down to the floor beneath
Speaker 2: it. It also kind of looks like a coltrop.
Speaker 4: Yes.
Speaker 3: One more thing that makes sense if you think about
Speaker 3: these organisms environment is that the deep sea tripod fish
Speaker 3: are hermaphroditic, so they can reproduce with themselves if they
Speaker 3: need to.
Speaker 1: That.
Speaker 3: They will of course reproduce sexually with others if they
Speaker 3: get the opportunity. But you know, you're down there in
Speaker 3: the deep sea, ships passing in the night or whatever
Speaker 3: the opposite vertical version of that is submarines passing in
Speaker 3: the night, you might not get the opportunity, So.
Speaker 2: Be prepared to do everything in house. Yes, all right,
Speaker 2: So as we begin to close out this episode, we've
Speaker 2: discussed several different deep sea organisms thus far that make
Speaker 2: use of bioluminescence in one form or another, and this
Speaker 2: is just such a fascinating realm of consideration for for
Speaker 2: deep sea fish. We were talking earlier about you know
Speaker 2: what happens when everything is just kind of like you know,
Speaker 2: a wide open chase, what happens when you're just bumping
Speaker 2: into each other and so forth. The other thing is
Speaker 2: that bioluminescence in this in this realm where light from
Speaker 2: the surface either takes on this this strange, you know,
Speaker 2: less intense form, or is just gone altogether. Bioluminescence light
Speaker 2: created in the deep by organisms. This becomes this whole
Speaker 2: place of interaction and weaponization. And I thought it might
Speaker 2: be fitting for us to go ahead and roll through
Speaker 2: all of the known uses for bioluminescence and fill in
Speaker 2: some examples for categorizations that we haven't talked about already.
Speaker 2: So the University of California at Santa Barbara has an
Speaker 2: excellent website about bioluminescence called simply the Bioluminescence web Page.
Speaker 2: I think it's been been around for a while at
Speaker 2: this point, but it's got some just great It's has
Speaker 2: some great visual breakdowns of the different categories of bioluminescence
Speaker 2: and you know, some examples. Uh. And they break everything
Speaker 2: down into three broad categories of function, offense, defense, and
Speaker 2: a third category that includes a single function and that's
Speaker 2: made attraction slash recognition swarming queue, and so I thought
Speaker 2: that would be a good place to start, and then
Speaker 2: we'll get into defense and offense, which includes some categories
Speaker 2: that we've touched on already. So when it comes to
Speaker 2: made attraction recognition and swarming queues, they mentioned several examples
Speaker 2: and possible examples for this category, because the thing about bioluminescence, well,
Speaker 2: first of all, I should stress that these categories tend
Speaker 2: to not be like one hundred distinct like so many
Speaker 2: examples will. We'll check off the box for multiple categories.
Speaker 2: I mean, such as the power of bioluminescence down there,
Speaker 2: there's a certain amount of drift and what it's actually
Speaker 2: achieving or seems to be achieving for any given species.
Speaker 2: And then, of course the other factor is we're still
Speaker 2: figuring out exactly what role bioluminescence has in any given species,
Speaker 2: especially when, of course, when we get into deeper species
Speaker 2: and rare species that we just don't know much about.
Speaker 2: But I'd say the most interesting example they bring up here,
Speaker 2: and probably you know key too our discussions, are the
Speaker 2: lantern fish of the family micto Fia day and they're
Speaker 2: found in more than two hundred and forty different different species.
Speaker 2: I've seen the species count as high as three hundred,
Speaker 2: and they're found worldwide. They're very abundant. According to the
Speaker 2: twenty eleven Encyclopedia of Fish Physiology, they make up sixty
Speaker 2: percent of all deep sea fish biomass, so, as you
Speaker 2: might imagine, that means they are very much on the
Speaker 2: menu for anything that is eating anything that's preying on
Speaker 2: fish in the deep ocean. They themselves, however, feed on zooplankton. Now,
Speaker 2: most species practice diurnal vertical migration, in which they stick
Speaker 2: to the depths of the bathoplegic zone during the day,
Speaker 2: and then they'll venture upward into shallower waters at night
Speaker 2: to feed. And as their name implies, lanternfish. They boast
Speaker 2: photophores that are certainly thought to help provide camouflage, breaking
Speaker 2: up their silhouette against filtered sunlight from above to protect
Speaker 2: against predators beneath, but some researchers hold that they may
Speaker 2: use these lights to communicate with each other as well.
Speaker 2: According to the Woodshole Oceanographic Institute quote, the arrangement and
Speaker 2: flashing pattern of these running lights are unique to each
Speaker 2: of the two hundred and forty five plus species of
Speaker 2: lantern fish, which suggests that they're not just used to
Speaker 2: camouflage the animals, but also to communicate. However, other sources
Speaker 2: I've looked at, such as that twenty eleven Encyclopedia of
Speaker 2: Fish Physiology, kind of downplay the possibility of a community roll. Okay, Now,
Speaker 2: there are other examples of organisms in the ocean that
Speaker 2: use their lights or seem to use their lights for communication.
Speaker 2: The ostracods, for example. These are tiny crustaceans noted for
Speaker 2: their blue or green bioluminescence. This is thought to aid
Speaker 2: and communication and identification as well. So again that's one
Speaker 2: way that bioluminescence can be used to sort of like
Speaker 2: say hey, I'm here, this is what I am, and
Speaker 2: so forth. But getting more into these like the offensive
Speaker 2: and defensive array, getting into the drama and conflict of predation,
Speaker 2: first the offensive use of bioluminescence, rolling through the different
Speaker 2: subfunctions that are outlined by the Bioluminescence website. First of all,
Speaker 2: luring prey we discussed a prime example of this with
Speaker 2: various deep sea angler fish create a light draw in
Speaker 2: other fish that are drawn to that light because it
Speaker 2: might mean a meal, or it might mean a chance
Speaker 2: to breed, and then you gobble up your prey when
Speaker 2: they get close. Now the next example, this one, This
Speaker 2: one's really interesting lure with external light, And this is
Speaker 2: one I hadn't thought as much about, but it should
Speaker 2: be common sense to us denizens of the sun and
Speaker 2: the moonlit world, and also a world where we've created
Speaker 2: a lot of external illumination sources. If you don't create
Speaker 2: your own deep sea light as a lure, might you
Speaker 2: depend on other species for illumination. Sperm whales, for example,
Speaker 2: may possibly seek out communities of bi iluminescent plankton, not
Speaker 2: to eat them themselves, but to watch for the plankton's
Speaker 2: defensive displays of bi iluminescence, which signals the presence of
Speaker 2: a predator, and this in turn would invoke the whales
Speaker 2: attack and Megamouth sharks may also employ this tactic. But
Speaker 2: I'm to understand that in either case we don't know
Speaker 2: for sure. I think this is this is still very
Speaker 2: mention in the realm of a of a hypothesis. Now
Speaker 2: here's the next categorization. Stun or confuse prey. It's thought
Speaker 2: that some squid may use bioluminescence to stun or confuse
Speaker 2: the prey species that they're after in addition to communication.
Speaker 2: In a two thousand and seven paper published in the
Speaker 2: Proceedings of the Royal Society, b Observations of wild hunting
Speaker 2: behavior and Bioluminescence of a large deep sea eight arm
Speaker 2: squid Teningia Dana, authors Kupadira at all right that the
Speaker 2: squid's intense light emissions quote may work as a blinding
Speaker 2: flash for the prey as well as a means of
Speaker 2: illumination and measuring target distance in an otherwise dark environment.
Speaker 2: Oh yeah, and they may also use their lights to
Speaker 2: deter count competitors and adversaries of the same species. So again,
Speaker 2: once you get into the use of this bioluminescence again
Speaker 2: that often it's multiple things. There may be multiple purposes
Speaker 2: in play here. But these are big squid, by the way,
Speaker 2: reaching lengths of one point seven meters or five point
Speaker 2: six feet, and their photophores, they're light emitting parts here,
Speaker 2: are enormous, often compared to fists or lemons. They're positioned
Speaker 2: at the ends of special arms, and they have what's
Speaker 2: described as like an eyelid like membrane, like a black
Speaker 2: membrane that closes over it. I included a photo here
Speaker 2: for you, Joe. It does indeed look like a great
Speaker 2: pale pupilis eye at the end of a squid arm.
Speaker 3: Deeply unsettling, this sort of large almond shaped chunk of
Speaker 3: white chocolate behind the behind the flesh. Yeah, but this
Speaker 3: is funny because it's like I'm thinking about the second
Speaker 3: half of the thing you mentioned here. The first item
Speaker 3: you mentioned is it's possible that the squid are using
Speaker 3: it to like a flash bang. It's there to stun
Speaker 3: or confuse the prey. But the other thing is why
Speaker 3: didn't I think of this before perhaps using it as
Speaker 3: illumination or way of measuring target distance, so essentially using
Speaker 3: it like a flashlight to illuminate prey so that it
Speaker 3: can better be located, the same way that if you
Speaker 3: were trying to like catch a chicken running around at night,
Speaker 3: you would need like to shine a flashlight at it
Speaker 3: to chase.
Speaker 4: Yeah.
Speaker 2: So yeah, this is this is an interesting example. And
Speaker 2: the full body. I found a great photo here of
Speaker 2: this particular species, and it looks kind of like a
Speaker 2: like a fighter plane too. Like you can really I
Speaker 2: have an easy time imagining this thing like zooming in
Speaker 2: on its on its target and then flashing them and
Speaker 2: then moving in for the kill, and then doing more
Speaker 2: flashing to say, hey, I'm at work here, everybody else,
Speaker 2: stay away, I've got yeah, all right, And that leads
Speaker 2: into the fourth example here of offensive bioluminescence usage, and
Speaker 2: that's to illuminate prey. So this particular species Tananingia dana
Speaker 2: may cover this example as well, but flashlightfish and dragonfish
Speaker 2: are also really good examples. So dragonfish of the Stomidae family,
Speaker 2: especially barbled dragonfish, are deep sea apex predators of the
Speaker 2: bathlevilegic zone. Absolute icon horror shows with needle teeth that
Speaker 2: look super intimidating on a poster. I actually had a
Speaker 2: listener write in, I think on Discord saying yes, I
Speaker 2: had the same poster, and I think maybe it was
Speaker 2: like a national geographic poster that had all these fish
Speaker 2: on it, a lot of deep sea fish. But this
Speaker 2: particular listener, also as a kid, didn't know how big
Speaker 2: these were. These guys tend to be like fifteen to
Speaker 2: twenty six centimeters in length, but there's still apex predators
Speaker 2: in their deep environment. They use their bioluminescent barbeles to
Speaker 2: attract prey as well as communication, it seems, but the
Speaker 2: species of loose jaw dragonfishes can produce red light via
Speaker 2: far red e midi photophorce to illuminate prey as well
Speaker 2: as help detect the red lights of their kin. According
Speaker 2: to Woodshole, they gain their red light abilities via their
Speaker 2: diet of copopods, and this is the only family of
Speaker 2: fish that can, via this method, produce red light. They're
Speaker 2: kind of like, it's like they're wizards of the deep
Speaker 2: that have a school of magic that most other fish
Speaker 2: do not have. But they're also of course competing with
Speaker 2: each other, so they want to know what the other
Speaker 2: wizards are up to. Included a photo here of Specimen Joe.
Speaker 2: Everyone else should look these up as well. Dragonfish as
Speaker 2: because their jaws are crazy. They have these like big
Speaker 2: hinge jaws that you know, it looks like some sort
Speaker 2: of mechanical device that might be employed here.
Speaker 4: It's a hr gig or mouse trap.
Speaker 2: Yeah, exactly, all right. Now, moving into into the defensive
Speaker 2: sphere of bioluminescence, there are multiple subfunctions here. So first
Speaker 2: they're the categorization of startling. Some squid use this, but
Speaker 2: also various dinoflagelet. Marine plankton use this technique. So when
Speaker 2: a predator moves in towards them, they begin flashing their bioluminescence,
Speaker 2: which in general has a twofold purpose. First of all, indeed,
Speaker 2: it startles the attacker. It's like, WHOA, what's happening? It started?
Speaker 2: It's flashing throws them off at least makes them hesitate.
Speaker 2: But also this bleeds into another defensive categorization, and that
Speaker 2: is what is generally called the burglar alarm. So when
Speaker 2: these particular marine plankton or other organisms such as some
Speaker 2: jellies flash defensively against predators, it also illuminates them and
Speaker 2: raises the profile of the attacker, So it raises the stakes.
Speaker 2: They're essentially saying, yes, you can continue to attack me,
Speaker 2: slash us, but you will do so in the spotlight
Speaker 2: where other predators can see you.
Speaker 4: Okay.
Speaker 3: So in a way, it's almost kind of like a
Speaker 3: small prey animal getting attacked by a medium sized predator
Speaker 3: screaming in the forest, and you know, one thing might
Speaker 3: be well, does that make the medium sized predator worry
Speaker 3: that a larger predator will come running?
Speaker 2: Exactly? Yeah? All right. Another category is misdirection, also referred
Speaker 2: to as the smoke screen technique. The vampire squid is
Speaker 2: a great example of this. These are smallcephalopods, actually neither
Speaker 2: squid nor octopod, but closer to octopods of the dark ocean.
Speaker 2: We have but one known species of the family vamporo Morophidia,
Speaker 2: and it is the vampo Tuthus infernalis, So it is
Speaker 2: the infernal vampire squid. When threatened, they'll eject not a
Speaker 2: pseudomorph of ink, so not like like a cloud of
Speaker 2: ink shaped like their body, but rather a cloud of
Speaker 2: bioluminescent mucus.
Speaker 4: Beautiful.
Speaker 2: So, not only is this cloud of biolumine us mucus distracting,
Speaker 2: drawing away a predator while the vamp makes its escape,
Speaker 2: but it's also sticky and glowing, So it also checks
Speaker 2: off the box for the burglar alarm, because if you
Speaker 2: get this stuff stuck on you, now you're glowing, and
Speaker 2: this is going to raise your own glowing profile in
Speaker 2: a most undesirable way, potentially drawing in predators that will
Speaker 2: eat you.
Speaker 3: Smart yeah, I mean, not like they thought of it themselves, but.
Speaker 2: Right right, all right. The next category, distractive body parts,
Speaker 2: a related concept here, But if you don't have glowing
Speaker 2: mucus to eject, you can always just jettison a glowing
Speaker 2: part of your body. The deep sea squid octopitoothis deletron
Speaker 2: may eject portions of its arm to serve as a
Speaker 2: glowing distraction while it makes its escape. And the interesting
Speaker 2: thing is here when you read about how it pulls
Speaker 2: this off. Apparently first they grasp their predator, like they
Speaker 2: sort of like go to their predator, but then they
Speaker 2: release part of the arm that is in contact with
Speaker 2: the predator it's glowing, and then they make their escape.
Speaker 2: It's kind of like jump in there, grapple your attacker,
Speaker 2: but then leave them your arm and make a break
Speaker 2: for it.
Speaker 3: Proactive glowing autotomy.
Speaker 2: Yes, sacrificial tag is the next one. There's a lot
Speaker 2: of overlapped overlap here with the distractive body part example
Speaker 2: we just rolled through, but the emphasis here seems to
Speaker 2: be on more of a burglar alarm type feature. So
Speaker 2: it's like basically they're saying, here, eat this discarded glowing
Speaker 2: part of me, but you will probably glow as well.
Speaker 2: Now because you have to remember, first of all, these
Speaker 2: sorts of tissues may continue to glow for hours, and
Speaker 2: many of these creatures are largely translucent, so eating a
Speaker 2: glowing meal could mean everyone will know you're there, they
Speaker 2: see the glowing meat inside you, and predators may notice.
Speaker 3: Ah yeah, So if your gut stuffed in cellophane and
Speaker 3: then you eat a glow stick, that does make you vulnerable, right.
Speaker 2: And this defense seems to have also caused the counter
Speaker 2: revolution of black line stomachs in many predator organisms to
Speaker 2: prevent the glow of bioluminescent meals from escaping, because obviously, yea,
Speaker 2: the more your stomach is like a dark room, there's
Speaker 2: going to be an obvious survival advantage if you're going
Speaker 2: around eating glowing food. And then, finally, the last categorization
Speaker 2: for defensive bioluminescence that the Bioluminescence website outlines is just
Speaker 2: warning colorization. This one overlaps with several examples. The glow
Speaker 2: is a warning of all the bad things that could
Speaker 2: potentially happen to the predator if they eat or try
Speaker 2: to eat the prey, and it also can communicate the
Speaker 2: old standby that we're familiar here on the surface world
Speaker 2: as well, and that is the warning, Hey, I'm not
Speaker 2: taste or maybe I'm toxic. I'm not good to eat,
Speaker 2: so stay away from me. Look how bright I am?
Speaker 4: Nice.
Speaker 2: So hopefully all of that helps to sort of flesh
Speaker 2: out what we've been talking about here in terms of
Speaker 2: bioluminescence in these various species that there's just there's kind
Speaker 2: of like a war of light going on in the dark,
Speaker 2: and it's fascinating how these different spells and counter spells
Speaker 2: interact with each other. Well said, and there's so many
Speaker 2: more examples, and there, of course, again there's so much
Speaker 2: more that we're continuing to learn about these bioluminescent creatures
Speaker 2: in the team.
Speaker 4: That's right.
Speaker 3: So maybe we'll have to return to this topic in
Speaker 3: the future, but I think for now that does it.
Speaker 2: That's right. So we're going to go ahead and close
Speaker 2: out this episode of Stuff to Blow Your Mind. But
Speaker 2: we'd love to hear from everyone out there. What's your
Speaker 2: favorite deep sea organism? What are some favorites that we
Speaker 2: didn't cover on the show here today? Write in We
Speaker 2: would love to hear from you. Will remind you that
Speaker 2: Stuff to Blow Your Mind is primarily a science and
Speaker 2: culture podcast, with core episodes on Tuesdays and Thursdays. On
Speaker 2: Wednesdays we air a short form episode, and on Fridays
Speaker 2: we have Weird House Cinema. That's our time to set
Speaker 2: aside most serious concerns and just talk about a weird film.
Speaker 3: Huge thanks as always to our excellent audio producer JJ Posway.
Speaker 3: If you would like to get in touch with us
Speaker 3: with feedback on this episode or any other, to suggest
Speaker 3: a topic for the future, or just to say hello,
Speaker 3: you can email us at contact at stuff to Blow
Speaker 3: your Mind dot com.
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