Episode Transcript
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Speaker 1 (00:00):
My Welcome to Stuff to Blow Your Mind production of
My Heart Radio. Hey you welcome to Stuff to Blow
your Mind. My name is Robert Lamb and I'm Joe McCormick.
And today we're going to be kicking off a series
(00:21):
of episodes about examples of throwing in non human animals.
We may also talk about the evolution of throwing in
humans as well, But this is a subject I recently
became interested in, specifically because of a paper that was
published in November. Some of you might have seen science
(00:44):
headlines going around about this. There was a publication in
the journal Plus one about octopuses throwing objects, or at
least potentially throwing objects. The whether or not it should
count as debatable, and we'll talk about some of the
arguments for for and against um. But octopuses at least
allegedly throwing objects potentially deliberately and potentially deliberately aiming those
(01:08):
objects at other octopuses. Uh. Though, of course, the exact
nature of their motivations is is somewhat mysterious. It's hard
to to suss out exactly. And I thought it would
be good to to start off our series by looking
at this example that first got me interested in this
um and then maybe we can branch out to other
(01:29):
examples of throwing in the animal world in subsequent episodes. Interesting,
I just assumed that your interest in this topic was
because you had become a father and you were already
feeling the poll You already were longing to throw ball
with your child, which which is something that that I
felt when when I became a father, I was like, well,
(01:51):
I've I've got to get a ball, right, I've got
to get a mit. I have no other connection to
baseball at all, or softball or any of these sports,
no attachment to them. I don't play of them or
watched them. But there's something about throwing that that must
be done with the child. I do like throwing a ball.
I think I'm more into like a tennis ball in
the hand than a baseball. But um but that's a
(02:12):
dog thing, that's for dogs. I guess that's true. Also,
Um No, I'm not talking about with like the scoop.
I mean the roller ball scoop. I mean tennis ball
straight in the hand. Okay, all right, but no, that's
not the reason. And if I were to go with
the the the motor activities, I've been thinking of more
(02:33):
since becoming a father would be the act of knocking
things over after they've been set up. I think that's
an interesting impulse that we could study. Oh yes, definitely.
But onto the octopus study. So this paper was by
Peter Godfrey Smith, David Sheiel, Stephanie Chancellor, Stefan Linquist, and
Matthew Lawrence, and it was called in the line of
(02:56):
Fire Debris Throwing by wild Octopus is published published in
Plus one. And so first I'm going to talk about
what the author's report and argue in this paper here,
and then we'll talk about some context as well as
some criticism or or differences in interpretation. Now, for for
(03:16):
background on this subject, I think we can safely say
that not a lot of animals throw things at all.
Throwing is a relatively unique behavior, and the authors of
this study say, quote, a throw can be distinguished from
other phenomenon by the ballistic motion of a manipulable object
or material, where ballistic describes free motion and momentum. So
(03:41):
when I think of throwing, I think of taking a
free external object or material, so not part of your
own body, and projecting it through the environment toward a target.
Throwing is so unique that it has sometimes been characterized
as exclusively the domain of humans. But there are a
number of animal behaviors that I think should count as throwing.
(04:04):
We'll talk about them throughout the series. Uh, some very
clear examples that I don't think anybody would really dispute,
like the throwing behaviors of primates like chimpanzees and capuchin monkeys,
right right, Yeah, there are plenty of examples of this
occurring both in the wild and in captivity. Not to
not to say they're not interesting. We may come back
to some of them, but but yeah, they're very well documented. Yeah,
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and uh, and also some very interesting ones in like
elephants and mongooses and birds and so forth. Now, if
you were to expand the definition of throwing to include
the projection of parts of the animals own body or
substances produced by the animal's own body, then the number
of examples really expands. Then you get all kinds of things,
(04:51):
Like you get spitting, which would include snakes. They're snakes
that project venom out of their mouths, out of their glands.
You have, of course, camels famously spit. All kinds of
animals spit, uh, and then you also have examples like spiders,
such as New World tarantulas. These spiders famously uh kind
of kick or shoot a little fibers known as urticating
(05:15):
hairs off of their bodies, and these are a defense
mechanism because the hairs can cause severe irritation to the
skin and mucous membranes of vertebrate animals that might threaten
the spiders. And you know, I've always thought of this
in the context of like tarantula itching powder, like it's
just an irritant. It's unpleasant, it gets on your skin,
(05:35):
it causes itching, makes you want to retreat. But apparently
in some cases of like the tarantulas with with more
severe hairs, this can even cause death in the cases
of some small animals when the when the hairs get
in their mucous membranes. Tarantulas are fascinating. I'd yet for
a return to the world of tarantulas again. But there
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are other spider examples too. You know, some other spiders
are known to project or throw threads of silk produced
again by their own bodies at prey to capture them.
But I think we probably don't want to count substances
produced by an animal's own body for throwing, because that
seems like a kind of that's a different class of
(06:18):
behavior than what we usually think about with throwing, because
when it comes out of the animal's own body, I
would think that usually tends to be an instinctual defensive
or predation mechanism. That's something that's probably just a wrote
behavioral program that exists. You know, it's evolutionarily coded into
the animals a nervous system, so they just kind of
(06:39):
do it automatically. Whereas the throwing of free external objects
found in the nearby environment, I would argue that indicates
a very different kind of underlying mentality, a much more
interesting and versatile type of tool use. Well, of course,
it's easy for us to say since our bodies don't
(06:59):
really produce weapons. Um it might be a different scenario
if human beings, say, produced and shed some form of
horn or antler or um or I don't know, had
had some other you know, let your imagination go wild.
But one might well imagine some sort of a humanoid
being that had some sort of evolved feature like this
(07:22):
That might blur the line. But but I, but I,
I do agree, yeah, with certainly with the human factor involved. Uh,
humans are are not really going to do much with
anything that their own body produces. They're gonna have to
turn to the things in the environment around them. Yeah,
it would be interesting if a human could like cough
up darts from their stomach on command. Now what now,
(07:44):
and I'm trying anything how to make that plausible? Okay? Now,
imagine you've got an animal that has a sort of
gizzard and they keep gizzard stones down there, and when
they need a weapon, they just vomit up a gizzard
stone and then they can throw that there. You go,
surely somebody's had done something like that. That would that
would that would be terrific. You have some sort of
like a kaiju bird and one of its attacks is
(08:04):
vomiting stones at you, and these stones could perhaps you know,
be used it as some sort of a siege weapon. Okay.
So that's the distinction between like an instinctual throwing or
projecting of part of your body or something that comes
out of your body versus throwing of things found in
the environment. Another distinction I would like to make about
throwing is the important, the important difference between throwing away
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and throwing at. For one example of this contained within
one animal. I think you could possibly make the argument
that the ant lion might exhibit both types of throwing
because it certainly at least does one. So the ant lion,
at one stage in its life cycle, it it lives
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down at the bottom of a pit that has steep
sloped sides with uh. You know, the sides are lined
with sediment of a certain grain size, and a prey
and see falls in it can't climb back out, and
then the ant lion kicks sediment or sand up at
the insect, and the insect falls down into its jaws
and it eats them. And then after it's done, it
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is typically known to fling the body out of the
pit by a similar motion to what it used to
fling the sand up at the insect falling in. Now,
I think you could definitely make the case that it
shows throwing away behavior because it's just rejecting the desiccated
exoskeleton of the of the ant that it has drained
(09:33):
of delicious juice. Is once it's done, right, yeah, absolutely,
But it may also display throwing at behavior, arguably because
as the ant is falling down, it will kick sand
up at the ant and uh, and you could argue
about whether that's actually at the ant or whether it's
just kind of generic sand throwing behavior that because the
(09:56):
real purpose, I think is not for it to land
on the ant, but to de ableize the walls of
the pit and cause them to avalanche downward, bringing the
ant further towards the bottom with the sand. Yeah. I
believe we talked about the ant line a bit in
our episode on the star lac Um, comparing the star
lacks imagined biology to the Antlin's very real biology, and yeah,
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they're fascinating little creatures. But the authors of this paper
also mentioned in the background how in some cases throwing
is a kind of tool use that also sort of
contains information. Like a projectile can be not only aggressive
and violent, but it can be a communicative social tool
(10:38):
between animals within a social species. And that brings us
to the example of the octopus. Is because one thing
it's really important to realize about octopuses is that they
are for the most part, not social. They are incredibly
anti social as far as animals go. With perhaps a
few notable exceptions, octopuses and really do not socialize with
(11:01):
other octopuses. They don't flock together they don't form groups
usually or have very complex social relationships. For the most part,
octopuses are solitary hunters, and when they do encounter one another,
they practice avoidance or sometimes outright violence. They will fight
one another and sometimes even cannibalize one another. Yeah, that
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that seems to be the extent of octopus politics. However,
despite their usual antisocial nature, there is some previous evidence
that octopuses might be able to communicate with or signal
information to one another. And an example that the author's
pick here is one that has some of the same
(11:44):
authors as this this studying question. It's by David Shield,
Peter Godfrey Smith, and Matthew Lawrence called Signal Use by
Octopuses in Agonistic Interactions, published in Current Biology in twenty
six and this study looked at the same species as
our main studies going to be looking at here, one
called Octopus tetricus, and this species can change color pigment,
(12:07):
can change the color patterns on its skin in a
number of ways, and this report found a correlation between
color displays on this octopus skin and intra specific behaviors
behaviors showing interactions between members of the species. The author's
right quote. Here we show by field observation that in
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a shallow water octopus Octopus tetricus, a range of visible
displays are produced during agonistic interactions, and these displays correlate
with the outcome of those interactions. Interactions in which dark
body color by an approaching octopus was matched by similar
color in the reacting octopus were more likely to escalate
(12:48):
to grappling darkness, and an approaching octopus met by paler
color in the reacting octopus accompanied retreat of the paler octopus.
So this is interesting. It raises the stability that even
though these octopuses are not very friendly with one another
and they don't they don't really want to hang out
and interact, they might still be communicating. They might be
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using color displays to at least communicate information about their
intentions with one another, and that could be beneficial to
both parties because it could help them avoid unnecessary violent conflict.
Like if you can change your color patterns to signal
like I mean business, I'm not going to back down,
or okay, okay, I'm not going to fight like that
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can help you avoid a fight that would have happened otherwise.
M M yes, yes, this of course, a topic that's
come up recently on the show and a couple other episodes.
We talked about the Galapagos tortoise, about the showdowns between
these big males and how uh it is almost, if
not exclusively, non violent in that they just have these
(13:52):
showdowns with their neck, who's the who's the tallest, and
whoever is the judge to be the tallest winds and
there's no need for actual violence to take place. Uh.
It also reminds me of the the episode idea with
Joe Burger while you were out talking about goats and
rams getting into conflict over mineral resources, and part of
the issue there it does come down to how goats
(14:17):
deal with this sort of conflict between each other, how
rams deal with the sort of conflict with each other.
But then when you have goats and rams, there's can
be kind of a communication breakdown. It's really interesting. Yeah, well,
I mean it makes you think about how much apparent
uh conflict and violence within the natural world actually doesn't
come to violence because animals are often looking for a
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way to avoid a fight. They just want to know
who would win and like find a way to sort
it out without having to do the violence. Yeah, even
in a lot of human combat, whether you're dealing with
individual level or more complex scenarios involving um uh, civilizations
and so forth, there's uh, you know, there so many
(15:00):
different way there's a lot of posturing. But then they
are also the the fights or battles one might get
into with the intention of being stopped by others before
the battle can take place. Like, there's so many different
things to consider though. I also want to come back
to this example I mentioned about the changing color patterns
on on these octopuses. I think you could also have
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non communicative interpretations of this as well, that that's possible,
but it's one good interpretation of that might be that
these animals are communicating with each other, they're sharing information,
even though they're not really a social species. Now, we
also know that octopuses are able to manipulate objects in
their environments using the surprisingly deft touch of the eight
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octopus arms raising the specter always of you know, possible
tool using intelligence and even maybe one day technological evolution
in the octopus. And we've seen many great examples of this.
One that I always think of is in octopus nest
building behavior. You r sometimes you'll find examples where um,
an octopus will be able to pull an an object
(16:07):
over the opening of its din in order to essentially
close the door, which I love. But also this study
mentions veined octopuses or anti octopus marginatus, which they say
quote carry can carry shelter in the form of nested
coconut shell haves that are then reassembled. You may have
seen video of this. Yeah, this is this is remarkable footage.
(16:30):
And I know just the just look watching an octopus
in the wild or in captivity. It seems to have
inspired many to imagine what it would be like if
they actually use tools and weapons. Um. I was I
was trying to remember where I had specifically seen an
image of an octopus with like a hatchet in one
of its tentacles. I imagine this was maybe an old
Dungeons and Dragons illustration or something. But I did an
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image search and I found that numerous people have have
painted some sort of scenario in which an octopus is
carrying a spear. I saw one where there's like a
spear wheel wielding octopus battling a samurai octopus. So there
is something about the the the octopus arms that we
we can't help but imagine them doing truly or weapony
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things with them. I'm not sure exactly why, but that
reminds me of the doom ba meme where people would
just like tape a knife to the top of their room. Ba.
I don't know if I saw that one, but that
sounds sounds dangerous. Thank thank thank, Okay, Well, anyway, these
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two different threads we've been talking about the use of
materials or arguably tools from the environment by octopuses and
behavior that might constitute social signaling between con specifics. These
two things come together in this studies. So the animal
in question in this paper is the species to Pus tetricus,
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also known as the gloomy octopus. Now why are they
called the gloomy octopus? Well, just look at their eyes.
Some people think that these animals have eyes that look
perennially unhappy. I don't know what I think about that.
It's it's hard to it's hard to read too much
human emotion into octopus eyes. But then again, I get
(18:22):
to staring at this and I don't know, maybe I
do feel kind of the mood coming down a little bit.
I don't know, Maybe I mean, I get kind of
a calm vibe off of this particular octopus. It looks cozy. Well,
they do like to be cozy. They like to to
hide in their dens. So the gloomy octopus is a
medium sized ben thick octopus ben thick meaning they live
(18:45):
on the sea floor and they occupy the waters around
Australia and New Zealand. But the particular population of animals
observed in this study live in a special zone along
the bottom of Jervis Bay, Australia, which is the coast
of New South Wales as it's south of Sydney. And
in this area along the bottom of Jervis Bay, many
individuals of the gloomy octopus live in very close proximity
(19:09):
to one another, high density, especially for octopuses, making dens
sometimes just right smack next to one another. Now, is
this a change and they're normally solitary antisocial nature, It
does not seem like that. There's no indication that these
animals like being near one another. Instead, it's a case
(19:30):
of a lot of octopuses trying to cram into a
spot that has both food abundance and excellent benthic strata
for making dens. So it's good real estate to make
homes in, and it's lots of great food, and it's
surrounded on all sides by terrible real estate, just sort
of featureless mud flats, which sort of prevents these octopuses
(19:53):
from spreading out. So for a human analogy, imagine a
kind of tiny island in the middle of the ocean
with of food on it, lots of great stuff there,
but it's just swarming with antisocial introverts who don't want
to talk to each other. I think I've had this
experience on most road trips I've taken. You know, you
find that one exit that has that one chain coffee
(20:14):
store that you need and can depend on. Um and Yeah,
an alien observing you might say, look at all these people.
They all love each other there, they love being around
each other. Oh that's good. So these spots in in
Jervis Bay have been nicknamed things like octo Lantis or Octopolis.
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A lot of just a lot of these antisocial non
buddies squeezing into a relatively small area. Naturally, there's gonna
be some conflict here. The octopus is regularly get in
one another's space, and this leads to the creatures poking
and grappling, grabbing, generally harassing each other. Now, it was
in studying this Jervis Bay population of Tetracus that the
(20:59):
author is first observed what they called a throwing behavior.
And the team collected many hours of video footage from
emplaced cameras from a couple of different sessions. I think
there was some footage from and from and uh and
they write quote here we provide the first report for
any octopus species of a behavior frequently seen at these aggregations,
(21:24):
the throwing or projection of debris, both in social interactions
and in other contexts. Ballistic motion of manipulable objects is
possible through water, albeit against greater resistance than through air.
These throws by Octopus tetricus sometimes hit other octopuses, So
they are throwing debris sometimes hitting other octopuses. And the
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big question is are they doing it on purpose? Are
they targeting one another on purpose? And if they are,
is that a social signal of some kind? Now, I
think it's important to first just describe exactly what's going
on here. When when an octopus is said to quote
throw something, octopuses do not throw the way humans do.
(22:10):
By building momentum with an arm motion and then releasing
or at least not most of the time. The team
apparently documented one case of an octopus throwing what looked
to be a bivalve shell by holding it in its arm,
quickly straightening the arm, and then releasing the shell. Uh. Instead,
what happens is most of the time the octopus would
(22:30):
throw by way of its siphon, and the siphon, also
called a funnel, is kind of a tube shaped organ
that octopus is used to swim. You can think of
it as an organic water jet. It's sort of a
pump that pumps water out the back and allows the
octopus to to by reaction, push its body forward. Interesting,
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so in in these in these cases of an octopus
throwing it, depending on what is being thrown, you could
think of it as being like they they've load did
their their biocannon, their their fluid based biocannon with like
a piece of shell, and are firing it. Or it's
just kind of like loaded with debris yet well sort of,
I mean that is good, I think, except actually what
(23:13):
the cannon is loaded with is just water as usual.
It's more like they've loaded a cannon and they have
put the thing they want to throw right in front
of the cannon so that when the cannonball comes out,
it hits the thing they want to throw. The cannonball
just being water and propels it towards the target. Again,
assuming that these are targeted throws. We don't know that
for sure, but going with that for a minute. So
(23:36):
it's a several step procedure. It goes like this. So
this octopus, Octopus tetricus, it will gather external material. And
there were three main types of material that the author's
observed being thrown in the study. One is shells, generally
mollusk shells, so like scallop shells, which also would be
shells of things that the octopuses are eating. And then
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the other one is algae, and then finally silt or
sediment from the seafloor, so just you know, sand, that
kind of stuff. This sounds like dirty Fighters. It sounds
like like the scene in so many movies, especially like
Sword and Sandal movies, where there's some sort of a
gladiatorial combat going on, and what does the villain do. Oh,
He's gonna get a little sand off the battleground floor
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throw it in the eyes of our hero, except the
gloomy octopuses are all dirty fighters. They love to shoot
this silt, so you scoop that up in your arms,
So they're actually using their arms for this part, scooping
up the thing, whatever it is, shells, algae, or silt,
and then they hold it underneath the body. They hold
it underneath the body with their arms, and then they
(24:42):
position their siphon underneath the body, which is not normally
where it is. They kind of hook it under so
that it lines up behind this stuff, and then they
release the stuff with their arms at the same time
that they blast it with a jet of water from
the siphon, and then that jet of water carries the
sediment toward its target. So again, this is very different
(25:05):
than human throwing. I think for a rough analogy, you'd
have to imagine that you could throw a baseball, not
by extending your arm rapidly and releasing it, but by
like holding the baseball in front of your face and
then suddenly releasing it from your hand and at the
same time blowing on it. Really hard to shoot it
off where you want it to go. And of course
(25:26):
in order to do this we need to have far
more lung capacity and diaphragm power than humans actually do have.
But just imagine you could briefly create like a little
jet engine exhaust port with your mouth. And this is
interesting because it reminds me of stories I've read elsewhere
of octopuses using directed siphon jets, but without any like
(25:51):
material being propelled other than the water itself. Like the
main thing is something of their stories of octopuses in
captivity squirting their handlers with water from their siphon, often
in the context of the handler believing at least that
the octopus is annoyed with them or being defensive. And
of course this is also reminiscent of of squid uh
(26:13):
using their ink in various ways, though of course that
would would obviously be an example again of an animal
using something created by its own body, rather than in
this case, using something from their environment. Right exactly so,
when the researchers watched the gloomy octopus do this throwing
of of shells, weeds, and silt, some of the instances
(26:36):
were obviously cases of simple rejection behavior, the throwing away
we talked about earlier, and a great example of this
would be what they classified as eating based throwing behavior.
So sometimes the octopus is going to eat, you know, uh,
a bivalve or something. Maybe it eats a scallop, and
then it throws the shells away. When it's done, it
(26:58):
actually projects them away from the body. Other examples of
throwing away behavior would be the classification they called den cleaning. Uh.
The octopuses actually do tidy up their dens. So they're
going to try to make a little hidy hole to
settle into on the sea floor. And sometimes I guess
it gets dirty in there, so they want to basically
(27:19):
blast a bunch of stuff out of there. And so
they will they will do this with their dens to
get things out of the hole. Yeah, you don't want
your midden to get out of control there with the
bones of your many kills or the shells of your
many kills. Other times, uh, they showed apparent throwing behavior
that the researcher said was anomalous. There was no apparent reason.
(27:39):
Maybe an octopus is just kind of like rippling arong along.
Nothing's really going on. It's not eating, it's not in
its din, nothing else is around, but it just kind
of throws something that didn't happen a lot. But occasionally
it did. And then finally, the last category they said
was was what they called interactive throwing. This is when
the octopus was interacting with another octopus or in a
(28:02):
few cases, another animal or objects such as a fish
or a camera. And these are the ones that are
really interesting because in this case, the researchers said, it
really looks like not just throwing away behavior, but throwing
at behavior. It looks like the octopuses are intentionally throwing
things to try to hit or discourage other octopuses in
(28:24):
their vicinity. So what proportion of throws are represented by
these different categories. Well, to read from their results, quote,
over half of all throws, or fifties three percent occurred
in interactive contexts, thirty six percent in interactive, only sevent
in interactive mixed. And that's where they're interacting with another octopus,
(28:45):
but also something else is going on, like maybe they
also just finished sheeting, or they're also cleaning out their den. Uh.
Thirty two percent occurred during den cleaning, only eight percent
after eating, and eight percent without a parent context. Oh,
and this total is more than due to rounding. But
they say that the material thrown and so, and then
(29:08):
there's another distinction they make throw interactive throwing, where they're
basically interacting with another octopus and they throw in that
octopus's direction, and then they make the distinction of, well,
did the stuff they threw actually hit the other octopus
on the footage they captured, and they said that the
material throne hit another octopus in seventeen cases that they documented.
(29:30):
In two other throws the material hit a fish, and
so co author David Shield said, speaking to the media,
it seems like there's a target and they're not throwing away,
they're throwing at But it is a difficult question, like
how can you prove that they're actually intending to hit
another octopus with this stuff when they do it. Of course,
(29:51):
it's possible they're just accidentally or maybe inconsiderately hitting one
another with these water jet payloads while they're doing somethinging else.
Maybe we don't know why they're doing it, and the
researchers aren't sure that these throws are intentionally targeted, but
they argue that on balance that is the more likely interpretation,
(30:11):
and that it possibly is some kind of social signal,
And they give a few arguments why they think it
is the more likely interpretation. So for one thing, Uh,
you might imagine that interactive throws are targeted and social
if you notice some patterns, like patterns of differences between
interactive throws versus other types of throws. And the researchers did,
(30:36):
in fact, documents some differences specifically between throws that hid
another octopus and throws that did not. One difference was
which arms are the octopus using. I thought this was
really interesting because it wasn't exactly what I would have expected.
But here's what they say. Okay, they say a total
(30:56):
of fourteen throws out of ninety eight that could be
assessed as anomalous arm throws, and these would be throws
using one of the side arms instead of just the
two front arms. Uh. They say, quote, anomalous arm throws
were more likely to hit other octopuses than L one
R one throws, and L one and R one are
(31:18):
the two frontal arms. So it seems like if you're
just cleaning out your den, you're just kind of throwing
stuff wherever you use the front two arms, but way
more often if an octopus throws something and it hits
a different octopus, they're using their side arms. Isn't that
kind of strange, and they found that the side arm
throws were less common overall, but more common if the
(31:40):
material hit another octopus. So something about this pattern of
arm choice could indicate maybe a type of aiming behavior
with hostile intentions. It's hard to know for sure, but
that is an interesting difference. They also write quote in
three cases of hits, a thrower also altered their body
orientation towards another octopus, but these movements were very slight,
(32:02):
and the effects of arm choice other than L one
R one were more marked. Okay, so that's one difference
between between throws that hit hit other octopuses and throws
it down. Second second difference body patterns and throw vigor.
These octopuses, as we mentioned earlier, can change their external appearance,
and in fact, they might even change their external appearance
(32:25):
in order to signal to other octopuses, maybe to help
avoid aggressive encounters. Uh And remember before when an octopus
displayed a uniform dark coloration, that was usually a sign
that they were displaying kind of like dominant aggressive behavior,
whereas maybe like turning paler might indicate that they were
(32:45):
willing to back away from a fight. The authors here
found that UH that throws that hit another octopus more
often took place when the thrower was displaying a uniform
and especially uniform dark body color. Quote. We note that
that throws by octopus is displaying uniform body patterns, especially
(33:06):
uniform dark patterns, were more often thrown with high vigor. Further,
throws by octopuses displaying uniform body patterns also hit hit
other octopuses significantly more more often than those in other
body patterns. And then also they say, in addition, high
vigor throws more frequently hit another octopus. However, with that
(33:28):
last point, they want to clarify, and I think this
is good to point out. High vigor throws, of course,
are because they're higher vigor, meaning thrown harder, they go longer,
and they have a wider range, which could explain more
frequent hits even if they're not deliberately targeting somebody like
a a random throw that goes farther and spreads farther
is more likely to hit something randomly than one that doesn't.
(33:51):
Another thing, they noticed material chosen when when octopuses through
something that hit another octopus, it was way more likely
to be silk as opposed to the other materials, which
appeared more often in other context. So maybe an octopus
is eating or cleaning its din, it's going to be
more likely to throw shells around. When an octopus gets
(34:12):
into a gets into an aggressive interaction with another octopus,
it seems more likely they will throw silt at them.
M hm. Back to the dirty fighter point. Yeah, yeah,
And there's something about, you know, the throwing of the
silt to that that I don't know that a lot
of this is just the human perspective and all, but
I know it makes me think of of things like
(34:33):
another trope from films, throwing a single pedal pebble at
a at a window pane to get somebody's attention. Uh,
you know, like you know where it's You know clearly
you're not you're actually trying to to harm anyone, but
you want to. You're creating a message. You're you're you're
sending a signal and in a different way. Uh that
there is a difference between pelting somebody with sand and
(34:55):
throwing a rock at them, like even in the human scenario, Um,
these are two These are two acts with rather different
messages if they were to happen, say at a beach
between two people, Yes, that that that's correct. Uh, So,
I think the material may make a difference there, though
they did say that the difference that they found in
material choice was not statistically significant because they're dealing with
(35:18):
a small number of samples here. There was a difference
in the numbers, but it didn't make statistical cut. Now.
One thing, they did also observe repeat offenders and aggressive patterns.
They say some particular octopuses would repeatedly throw and strike
another one again and again and again, and this kind
(35:38):
of repeated hit behavior would seem to indicate a deliberate,
targeted pattern more than an accidental one. The authors also
say quote hits in many cases occurred within sequences of
interactions that featured ongoing mild aggression, including arm probes and
momentary grappling. So they're saying we saw throws that hit
(36:01):
another octopus, often when octopuses had already been tussling a lot.
Mm hmm okay, And in another way of stating it,
some octopuses might just be jerks. One last thing, they
say there were defensive behaviors. Uh. The apparent victim of
the throw often reacted by either holding arms up to
block the jet of material flying their way, or by
(36:24):
ducking and dodging out of the way. Uh. And they
said sometimes octopuses who had been hit altered their behavior
in some other way, by say, like pausing or halting
or redirecting their movements. And this last point I think
is really important because the authors say, you know, even
if these throws are not actually socially intended, they do
(36:45):
appear to have social effects, Like if they cause redirected
movement in the victim, that would seem to be a
socially relevant behavior. Even if you would I don't know
exactly what it would mean in this case though, to
say that they were not intend to be social signals
by the by the individual throwing. Yeah, it's so. I mean,
(37:06):
it's it's an impossible task to try and do, to
try and put yourself in the mind of an octopus,
but you can't help. But wonder, coming back to some
of what you said earlier, like is it is it
potentially indeed like a directed action where the octopus, in
its own octopus way, is quote unquote thinking I don't
like you, I want you to go away, or something
(37:28):
I will throw sand at you. Or is it like
the octopus is throwing sand while having a certain hostility
towards other octopuses or a particular octopus, and in doing so,
these things kind of a line and maybe there's there's
less intention there. I don't know. Oh no, that I
(37:48):
think that's a really good point, and that comes up
in one of I think the better criticisms of the
study that I want to get to in just a minute.
But just before I do that, I want to mention
a few other things that the author's highlights several things
they did not see. Uh, and I think it's worth
paying attention to what these are. They say, you know what,
we never saw an octopus quote return fire, So they
(38:09):
never saw a throw hit initiate any kind of violent
retaliation by the target. That they did see the targets
like it might make them sort of go away or
redirect their movements. Thank thank They also say, and I
(38:31):
thought this was quite interesting quote. Some throws in what
appeared to be fairly intense interactions were not directed at
another octopus but into empty space. So octopuses might be
tussling pretty strongly, like they're fighting each other, but then
in the middle of that, you know, prolonged aggressive interaction,
(38:52):
the octopus just kind of like throws some material but
not at another octopus just throws something. Almost invites comparisons
of just like throwing things in a huff. But I
don't know if you could say that's what's going on
with an octopus. Yeah, yeah, no, you can't help. But
but but think that again putting the human lens over everything.
(39:12):
But anyway to come back with some uh, some criticisms
of this type of interpretation, I was reading an article
in the Atlantic by Marina Corn called everyone has an
Octopus opinion and uh. This article collects some arguments that
there might be less than meets the eye when it
comes to the octopus throwing footage uh and saying that
(39:34):
the interpretation of socially targeted throwing might just simple simply
be anthropomorphization. So a few things that that are collected
in this article. One is that Coren documents a dissenting
opinion from an evolutionary biologist at San Francisco State University
named Robin Crook, who questioned whether this behavior really counts
(39:56):
as quote throwing because of the physical processes in oolved noting, again,
like we talked about earlier, that while octopuses will grasp
things and pass them around with their arms. They don't
use their arms to throw the way we do. Instead,
they use this this siphon blasting maneuver, which to Crook
does not constitute throwing. I don't know if I would
(40:18):
really like make this distinction. It seems to me like
the important part of throwing is like the intentional ballistic
projection behavior of objects from the environment, not so much
like the muscle movements you use to do that. But
I don't know what you think. Yeah, I mean a
lot of it's just gonna come down to the body type, right, Um,
and uh, what kind of tools you have to to
(40:39):
to send stuff fly in at another creature? Really? I
keep coming back to children and all of this. Um,
I can't can't wait for you to take everything in
this episode with you when you start taking your your
child to the beach, because um, yeah, a human child
is is certainly an education and all the ways that
(41:00):
you can you can send sand flying in the wrong
directions as well as as various other objects. They can
kick it, they can throw it, they can shake it
from from towels. That's wonderful. I have so much magic
of that kind of look forward to. Um, But no,
but so so so, Krook says. Another thing is that, uh,
you know, like we were talking about there, there are
(41:22):
other contexts in which octopus is clearly show this kind
of like siphon blasting behavior, such as cleaning up their
dens after a big meal, you know, blasting a bunch
of mollusk shells out, and Kirk argues that maybe that's
all that's happening in the footage that's examined in this paper.
Sometimes they're just blasting their dens out or doing a
behavior that they do when they blast their den's out
(41:44):
and hitting other octopuses by accident. In the total footage,
this article claims that only seventeen percent of the throws
actually hit another octopus, So a majority of what we
see either way is just throwing away behavior, not throwing
at the question is whether this minority of cases where
it was interactive throwing, and especially the ones where it
(42:07):
looks like interactive throwing and it actually hit the other animal,
those are the minority we're looking at. That's just seventeen
percent of all the throws. Yeah, I mean, I again
come back to something you mentioned earlier about again the
the octopus is generally a solitary creature, and this is
a scenario in which they are living in close proximity
(42:27):
to one another due to the restraints of the of
the environment itself. So you could just simply look at
it like, look, these octopuses are are violent slabs, and
normally they're on their own being violent slabs, but now
they're forced to live together, and this is this is
what happens when occopuses, I don't know, stop being polite
(42:48):
and start getting real. Now, there are several things raised
in this article, but one I thought was actually a
pretty good point to make was that even if the
octopuses are trying to hit one another with the throwing,
so maybe you can say, like half of the equation
is true. Maybe it is targeted throwing. They are throwing
at the other octopus. But at the same time you
(43:09):
could say it might still not be social octopus signaling
exactly because in the words of Piero Amodio, a biologist
who has specialized in octopuses at anton Dorn Zoological Station
in Italy, it maybe quote used more broadly towards annoying
or threatening stimuli. So maybe it's not a thing about
(43:31):
octopuses communicating with octopuses, but it's just like something is
bothering them, so they throw They just squirt object, they
squirt material at it. Uh And evidence for this would
include octopuses were also observed in a couple of instances
in the study throwing debris at fish uh and at
a camera emplacement in a couple of cases. So it
(43:52):
could be less interspecific social signaling and more like, I
don't know what that is, I don't like that object
in my space. Squirt some dirt at it for this objection,
I think fair enough. Like in that case, I think
it would definitely count as directed throwing. It would be
throwing at rather than throwing away. But this might limit
what kinds of interpretations we could make about the relationships
(44:16):
between gloomy octopuses specifically. The article makes uh sites. One
last argument that I thought was pretty interesting, and this
comes from Christian now Roth, who is a researcher on
the behavior of goats at the Research Institute for Farm
Animal Biology in Germany. And the point that Narrowth makes
(44:36):
here talking about goats is that, yeah, even goats have
lots of mysteries about them. Quote, they sneeze when they're
spooked or frustrated, and there is actually nothing on how
often goats show this behavior, how often they use it,
in which contexts they use it. Uh And I thought
that was really interesting because it, of course is especially
(44:57):
hard to figure out the motivation for animal behavior when
you're studying them in the wild as opposed to in
the lab. Like in the lab, you can strictly limit
variables to some degree, but in the natural environment there
might be thousands of variables to disentangle, and you might
not even recognize what some of them are. And the
specific example about okay, so goats sometimes sneeze when they're spooked,
(45:20):
but like, why do they do that? What exactly are
they trying to do with the sneezing. Is it a
directed behavior or just to kind of tick or what?
It reminds me of our recent discussion on the Galapagos
marine iguana. Do they sort snort salt out of their
salt glands at an attacker defensively, like when something is
(45:42):
approaching them, when when a Charles Darwin is approaching them,
as Charles Darwin thought he observed, or is the salt
snorting not actually correlated with with defensive behavior? Is it
not actually motivated by defensive considerations at all. It's hard
to tell. Yeah, again, it is so hard to step
outside of the um of of the human lens here
(46:06):
when when trying to imagine what any of these creatures
are doing. Um, because some of these things, like we
we want to interpret them and think about them as
being deliberate actions as opposed to say, in the human scenario,
sort of uh, incidental signalings of hostility that we might have.
(46:28):
Like someone can look hostile and say a bus without
actively thinking like, oh, I'm going to show everybody on
this bus how I feel about them. Check out my hostility.
Don't come near me or or violence happens next, like
you could. That person could just genuinely be and say
a bad mood or be thinking about something that's bothering
them and their their posture, that the way their their
(46:50):
their look, their expression on their face could take on
a hostile energy that would then be picked up on
by other people. And that and that kind of ambiguity
exists even with in our very finely tuned ability to
suss out the motivations of other humans. These are on specifics.
We're right in that human meal you you know, we're
used to that when looking at another species. I mean,
(47:12):
it's like several orders of magnitude more difficult to figure
things out right, right, Because again, that same dude on
the bus that you're thinking looks hostile, he could just
be thinking about a really cool episode of some TV
show that he watched, you know, and that's just all
you because you think, oh, somebody who looks weird on
a bus must have hostile intentions. Uh, they must have
(47:33):
something negative going on, and they don't just have an
intense look because they're trying to figure out the plot
of of I don't know, some Netflix show. Now, I
think when it comes to the ambiguity behind animal behaviors,
there might be other kinds of considerations that would come in, Like, okay,
is the marine iguana even if you could show, wow,
it does, uh, you know, snort salt out of its
(47:54):
salt glands more often when a human is approaching it,
That would show a correlation with the proximity of a
larger land animal. But it wouldn't, Uh, it wouldn't still
wouldn't show it was defensive in some way. I mean,
maybe it's snorting like that because it's trying to I
don't know, like clear, some kind of gland blockage in
case it needs to move quickly or something like that.
Maybe that's part of the kind of fight or flight uh,
(48:17):
physiological internal regulation of the iguana's body. Who knows. I'm
just speculating there, But you could imagine other things for
this octopus throwing behavior. Maybe the throwing is part of
something that's going on internally with the octopus that is
related to aggressive interactions with other octopuses, but is not
(48:39):
about hitting them with the objects, though it's hard to
figure out what that other purpose would be. Then again,
maybe it is just about hitting them with the silt.
I mean, that seems like a perfectly plausible explanation to me.
Either way. A fascinating look here, another fascinating consideration of
the world of the octopus. And this episode is also
(48:59):
kind of a stealth goat episode two, since we get
to get in a little bit of goat pondering here
at the end. I like that. But we're gonna be
back with more interesting examples of throwing behavior and animals,
so these questions will continue, that's right, so be sure
to join us for the next one. Um, let's just
remind everybody that's stuff to Blow your Mind publishes in
(49:20):
the Stuff to Blow Your Mind podcast feed with our
core episodes on Tuesdays and Thursdays. On Wednesday's we do
a short form artifact or monster fact episode, on Monday's
we do listener mail, and on Fridays we set aside
most serious concerns to just talk about a weird film.
Huge thanks to our audio producer Max Williams. If you
would like to get in touch with us with feedback
(49:42):
on this episode or any other, to suggest a topic
for the future, or just to say hello, you can
email us at contact at stuff to Blow your Mind
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(50:03):
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