Hey, Please take a second and leave us a review on Apple Podcasts, Spotify, or wherever you listen to the podcast. Thanks a lot. Hey, welcome to Sign Stuff, the production of iHeartRadio. I'm More Hey, chim and today we're answering the question do animals have consciousness? Have you ever looked into your dog's puppy eyes and wondered what's going on in there? Can animals have thoughts, sense of self and even dream What about chickens, or fishes or even bugs?
Can they have an inner world and feelings? To find out, we're going to talk to a couple of experts on animals sentience, and we're going to learn how to tell if an animal has consciousness, which ones have it, and we're going to ask the big question about what it would mean for them to be conscious. So dream along with us as we answer the question do animals have consciousness? Enjoy Hey everyone? Today on the episode, we're going to
find out if different animals have consciousness. We're going to learn whether the monkeys have it, where their dogs have it. We'll even talk about whether their chickens and crabs have consciousness. Now, consciousness is a super tricky topic, so the first thing we're going to do is define what consciousness is. And to do that, I reached out to an animal philosopher. Here's doctor Heather Browning.
So I'm doctor Heather Browning. I'm a philosopher who works at the University of Southampton, and I'm most interested in using the methods of philosophy to answer questions about the minds of animals. So animal sentience and animal welfare incredible.
First of all, can you tell us what is consciousness?
All right? So we start with the really big questions. So consciousness is something that's proved notoriously difficult to define. A lot of philosophers try to think really hard about this, and essentially, when we want to talk about consciousness, I think the best way is to think about it through examples of the kinds of experiences that are familiar to us. So you might think that, for instance, a rock doesn't feel anything when water falls on it, but we do.
When a grain falls on our skin, it feels like something. For that, when we're asleep, it doesn't feel like anything to be us. When we're awake, we're seeing, we're smelling, we're tasting. All these experiences have this quality of feeling that are associated with it, and that's what makes up consciousness.
Okay, so it's very tied to the idea of a feeling.
Yeah, that's right.
So one way to think about consciousness is that it's the opposite of being a rock. Rock exists in the world and things happen to it, but it doesn't feel anything. It doesn't have thoughts about the things happening to it. Basically, there's nothing going on inside of a rock. Another way to think about consciousness is that it's also kind of
the opposite of being a robot. You can imagine making a robot that looks like a person in this program to act and respond like a person, but that robot we don't have an inner life the same way you do.
But when I look at another person, the only information I have about them really is the words that come out of their mouth and the behaviors that they do, and they all resemble mine in a lot of ways. But technically that person, you know, they could be sort of an android with nothing going on inside, or they could be what philosopher's like to call philosophical zombies, which is a person who essentially is like a robot. You know, if there's no kind of light on, no spark.
Now, there are other things that are part of being conscious. For example, some people say having consciousness is having a sense of self, you know, like a feeling that you're a person in this world. Another part of consciousness is having the power to make decisions that you don't do things automatically, but that you think about them. There are lots of definitions, but for now, just hang on to the phrase. It means that you have an inner life. And so the question now is do animals have this
inner life? Well, the problem is that we can't ask them.
Yeah, So, I mean this is something philosophers like to debate a lot, and they call it the problem of other minds. And we don't know when we look at another person, we don't know for sure that they're not a philosophicals on video, they're not an android. And I mean, right now you're just seeing me on a screen. I could just be an AI. You know, shot out. That's from program.
I Am an AI. By the way, you're being interviewed by an artificial interviewer.
We're very sophisticated on us.
Thank you. We worked on it a lot. What doctor Browning is saying is that it's hard enough to know if another person has consciousness, much less an animal we can't even communicate with, So how can we know if an animal has consciousness? Well, it turns out scientists have come up with sort of an animal consciousness test to tell us about it. Reached out to doctor Alex Schnell.
You might remember her from a few episodes ago. He's a comparative psychologist who is all so in National Geographic Explorer, and she talked to us about how smart octopuses are. It turns out she's also a researcher on animal consciousness. Well, thank you, doc, there's not for joining.
Us again, thank you for having me.
Are you conscious right now?
Slightly? It's about thirty two degrees celsius. I don't know what that is fahrenheit, it's very very high.
Scientists like her study consciousness and animals have come up with a set of indicators or tests that can tell you whether an animal potentially has consciousness. What does that mean? What are the indicators? I guess?
So the indicators are We've got four that are neural that really look at the presence of nose receptors, so receptors that can respond to stimuli like a prick or heat or an electric shop whether they have integrative brain regions where that information can be combined and integrated.
So the first indicator scientists used to tell if an animal has consciousness is whether the animal can feel pain. And really the scientists are interested in whether the animal can feel anything, but they pick pain because there's a lot more data out there on it. Then see whether an animal feels happy or sad. Okay, that's step number one. Now, if an animal does feel pain, the sign of consciousness is what the animal does about it.
Yeah, And then behavior indicators include protective behaviors. So you've brought octopus, so I'll tell you for an example, if it octopus is inflicted in with something that might cause pain or harm, they generally show protective behaviors that you might see in your pet dog or cat at home. You know, they'll stroke their arm or rub their arm, or wrap their injured arm really close to their body and protect it with their other arms, and they won't use that as often.
Interesting, So a sign of consciousness is if an animal feels pain and then acts to protect where they feel the pain, because that means they have a feeling and they're conscious of it. It affects how they behave The next step is whether they learn from their experiences.
Another indicator is learning from experience, just learning that doing a particular activity, if you're getting a negative emotion from that, to stop doing that.
So if an animal feels something like pain and they stop doing it, that's a sign that they're in a way thinking about that feeling and that they have learned what caused that feeling. That's another sign of consciousness. And the last test of whether an animal has consciousness is whether they can make choices that trade off different feelings.
And then also the last one is showing a preference or an aversion to an experience that is going to have a particular vailance. So if you keep getting stung or prodded in one particular room, then you might avoid that room in the future.
Okay, these are going to make more sense a little later when we apply these tests to different animals, and I think you're going to be surprised how some animals, even bees, respond to these tests. So this is a list of indicators that let's say an animal checks all of the boxes, then it's a very clear candidate that it may be has sentients and maybe consciousness is how you would phrase it.
So definitely like Marx that there's strong evidence that they are sentient.
Okay, when we come back, we're going to apply this set of tests to a wide range of animals, including dogs, chickens, hermit, crabs, and even bees to find out which of them have consciousness. So stay with us. We'll be right back, and we're back. We're talking about whether animals have consciousness, and so far we talked about what that means and how you might
tell even animal has it. Scientists who study this have somewhat of a test for consciousness or sentience as some people call it, which involves looking at how animals react to pain. How they react to, for example, getting tricked by a sharp object or getting a slight electric shock can tell you a lot about whether they have feelings and whether they have complex thoughts about those feelings. And again, they use pain because a lot of the research out
there focuses on whether animals feel pain. Now, the question is which animals pass this test to Monkeys, dogs, birds, crabs, or even insects show signs of consciousness well. According to doctor Heather Browning, it's kind of hard to tell.
Yeah, I think there's still a lot of uncertainty and controversy about which animals are conscious or which animals are sentient, because this is something that we're talking about that's happening inside their heads, inside their minds, and we don't have, you know, a consciousness scope that we can just go and look into the minds of animals and tell us what they're thinking or feeling. We don't even have that for other humans.
Now. The thing about consciousness is that most scientists don't really see it as a kind of on or off thing, meaning that you either have it or don't. The more common view is that it's something that's on a scale.
So that is something that there's still debate about, and I think people aren't sure because I think intuitively it makes sense to us to think about it as being on or off, but that doesn't trap very well with how we think about a lot of the rest of biology. When we think about the kinds of evolved traits that other animals might have, often they do come in degrees.
You know, Yes, some animals can fly and some animals can't fly, but there's all kinds of gradients in between there where some animals can glide, some animals can fly a little bit, and some animals can't do that at all, And so it makes sense that almost all traits and biology are actually on these kinds of gradual scales, and consciousness is probably something.
Like that, Yeah, well, I feel like right now we're in a very different time zone, and so I am only partially conscious right now myself. Yes, okay. According to this definition of consciousness, doctor Browning says most experts agree that most mammals, down to about a dog or a mouse, demonstrate signs that they have consciousness. It's clear that they have feelings and that there is some kind of inner life going on inside their brains.
So it's very very difficult, I think, for anyone who's had a pet dog and spend any time with it to really, you know, and not think that there's someone there on the inside in the mind of that dog, but they're really interacting with another being or another subject there.
So there isn't much debate about whether animals like dogs or horses, or elephants, or pretty much any mammal has some form of consciousness. Where it gets triggier is in animals like birds, or even chickens.
Yeah, so I think what chickens get over looked quite a lot. But yeah, they are actually quite cognitively complex animals. You know, chickens can learn very well, they have good memories, they make complex decisions, they have complex social lives. You know, they're able to remember and interact with a lot of different chickens as well, and thinking about what they feel. Certainly we see chickens that have the kinds of injuries that we would think would be painful when a human.
They will preferentially go and eat food that has a painkiller in it. Even that food tastes worse and a normal chicken that wasn't in pain wouldn't want to eat it, which you know, is very strong evidence in my mind that they are feeling pain, that there is something there that they're trying to stop, just like we would.
I see, there are things they like and they things that they don't like.
Yeah, that's right, And a lot of work in animal welfare science is trying to look at, you know, what animals like and don't like through doings that they call preference testing, you know, giving them different situations and seeing what they choose.
Okay, this is part of that test that I mentioned to you before. Here's what the experiment looked like. You offer a chicken two balls of food. One are the bulls is food that tastes great to a chicken, and the other ball has food that doesn't taste that great to chickens. Now, normally chickens will choose the food that tastes better, But if the chicken is in pain for some reason, and you put pain medicine in the food that tastes worse, the chicken will choose the one with
the pain medicine. And this, scientists argue, is a sign that chickens can feel and have a preference and make a choice based on that preference, all of which are signs of consciousness.
And chickens have been the subjects of a huge amount of these tests. And you know, do they prefer to stand on the floor, do they like to be on a perch? Do they like to be in a nest box? Or do they like to nest in a corner on the ground. And yeah, they're very good at telling us that, And it really does seem like they have those kind of rich sets of preferences about what they want and what they don't want what they like and what they don't like.
Okay, the next animal we're going to talk about are fish. Do fish have consciousness?
So fish a roment of travelers. They ran into a lot of skepticism because their brains are very different from ours, and so the kinds of inferences that we make from our types of brains and saying well, look, other animals have brains that are similar, so they probably produce the
same kinds of experiences. You should have different kinds of brains, And so people wanted to use that as a reason to say, well, they can't have consciousness, And people who worked with fishes and look at their behavior wanted to push back on that and say, well, no, a fish might have a different brain than ours, but we might still be able to have consciousness. Fish do a lot
of these sort of complex things. They respond when they receive I mean we would think would cause pain, or if they get an injection in their lips of a mild acid that should cause them pain, they will wrap their face on the tanks, they will lose interest in their food, They'll be less likely to respond to predators because they're distracted. They will preferentially go to tanks. They
have painkillers in them. All those same kinds of responses that if we saw them in a mammal or a bird tho sort of experiences we see in fish.
So according to our definition of consciousness, fishes are conscious beings too. They have feelings, they can feel things, and they have complicated thought processes that guide how they behave. Okay, now we get to even trick your animals. Invertebrates. These are animals like crabs and shrimps and octopuses and insects. Can we say that they have consciousness too. We'll start with an easy one, which are octopuses. Here's doctor Alex Schnell.
So, for example, we looked at three hundred studies by way a team of scientists led by Jonathan Birch to find evidence of sentience in cephalopods and decapod crustaceans, and octopus satisfied seven of the eight criteria, and the one that it didn't satisfy studies in that criteria had not been conducted.
So octopuses passed seven of the eight indicators that tell you they might have consciousness, and some sodis even show that octopuses might even dream.
There was some other research that's not my own, but some researchers in Brazil had conducted on octopus looking at different phases of sleep, and this was so cool. They showed that octopuses have two phases, a quiet phase and an active phase, and their active phase looked very similar to the way that humans sleep during RAM, so the rapid eye movement phase, and in humans that is a
phase when we dream. And so they had a lot of behavior footage of an octopus clearly asleep because their eyes are closed and they'd be prodden just to make sure that they're asleep, but changing coloration and texture is if they were having a dream. You know, sometimes they look like they were outfeeding and hiding for a predator. So wouldn't that octopus be dreaming? You know, there's still a huge question mark, but it was pretty phenomenal.
To think that is fascinating. Well, I guess, first of all, I didn't know octopuses slap, but that the dream is amazing and that you can see it in their coloration. They might dreap, sorry, that they might dream, yeah, and that you might be able to see it in their coloration and their movement.
That's incredible because there's not many other animals. I mean, you can see a dog when they you know, they might be dreaming and they're running in their sleep and they're whimpering like they're trying to catch something.
You can see that in dogs. I don't know inn a dog.
So oh, okay. I think there's a whole community of YouTubers that share results and videos their dogs and cats dreaming. It's very entertaining. But yeah, you can. But there aren't many animals like an octopus where you can actually see the color of their skin changing. And so I like to think that they wear their emotions on their skin and maybe that's a window into their mind.
It kind of makes you wonder what does an octopus dreap about? Okay, So that covers octopuses and like extension, also curdlefish and probably squids as potentially having consciousness. Now we get to even trickier animals like crabs and these do insects have consciousness? We'll review the scientific evidence for it after the break. Stay with us. You're listening to
sign stuff and we're back. Okay, we're talking about whether animals have consciousness, and so far we talked about what that means how to tell if an animal has it. And we've gone down the evolutionary tree of life to see which animals can be said to possibly have consciousness, And now we're at animals that are very different from us, the invertebrates, invertebrate animals, that is, animals without bones or a spinal cord, separated from us, or we separated from
them over five hundred and ninety million years ago. And yet invertebrates like octopuses clearly have intelligence and can be said to have a consciousness too, even perhaps to have dreams. But what about other invertebrates like crabs or shrimp or even insects. We'll start with crabs. So crabs, what was the evidence of crabs?
Yeah, so crabs action there was a surprisingly large amount. We went into the project assuming that there'd be quite a lot about octopuses, because we know people find octopuses very interesting, but crabs. Actually there was almost as much
evidence in crabs as there was in octopuses. So hermit crabs are crabs that don't have their own hard shells, but they move into the shells that are left behind by other sea creatures and they change those shells over time as they grow, or if they find a better shell.
Okay, here's the experiment that's been done with hermit crabs, and it's pretty interesting. This was done by a biologists named Bob Elwood. Elwood and his team gave hermit crabs the choice of different shells to pick for their new home. But all the shells were rigged. Each had a little ho all drilled into them with the wire that went inside the whole. Now, the hermit crab would try on all the shells and eventually pick the one the crab liked.
But here's the twist. After they picked a shell, the scientist would send a mild electric shock to the crab through the wire place inside the shell. So now the hermit crab had a problem. The shell they liked had this annoying quality that it would shock them every once in a while, and so they had to make a choice should they stay or should they go and find
a different shell. The hermit crabs would get a variety of different shells qualities, and some of them would give them a shock, So they really had to think about, well, which shell do I want?
Yeah? And can I sustain that shock? And just to keep this great house that I'm in or I'm just going to get rid of this house and go for one that's of less equality to me.
Well, what they showed is that if they were in the good shell, they'd be much less likely to leave it. I'd be much slower to get out of it than if they're in the badge. And so, you know, they were showing that they valued these shells, that they really did make this kind of decision based on the badness of the shock versus the goodness of the shell.
And then the scientist made it even more complicated for the crabs. They would sometimes put in the water the smell of a predator that tries to eat the hermit crab, And so now the hermit crab had to make an even harder choice. Should I stay in my preferred home even though I'm getting shocked, or should I take the risk and go find another shell, even though it seems there's something out there trying to eat me.
And so they would have to integrate the risk of getting the shock and maintaining that home and trade off between those risks and opportunities. And so it really told a nice story of how hermit crabs why they might not have an inner monologue. They to have the capacity to integrate this information and make decisions based on that integration.
You would have thought that of all animals, the hermit crab would have a monologue. They don't really talk to any other crabs. Yes, so even crabs seem to pass the test or potentially having some form of basic consciousness. Now, at this point you might be wondering, how far does this go? Do all animals have consciousness, even insects? Well, it turns out the answer is maybe, Okay. So then if we keep going down the complexity of animals from
shump you and crabs, you would get insects. And so what do we know about insect consciousness?
Yeah? So I think insects report will you wear a lot of the players right now? I think that's where people are paying a lot of attention the question of insect consciousness. This is because our use of insects is increasing, Insect farming is set to rapidly increase over the coming years, and so the question of whether or not they're sentient is becoming very very relevant to the ethics of insect farming.
What do you mean insect farming for what? For food?
For humans? So insect farms, So say, crickets for instants are being seen as potential sources of protein for humans. Know, when we're struggling to feed the world in a way that has kind of you know, effishient, environmentally friendly protein sources and also more than that, as food for the animals that we feed. So black soldier fly larvae in particular are being used quite a lot to feed feed chickens, to feed fish in aquaculture.
Okay, all right, so then what do we know about insects sentience?
So there was a relatively recent review done of the evidence for sentience and insects, very similar to the one I was talking about that we did in cephalopods and decapods, and again found quite positive and promising results. They ran into many of the same problems in that there's not a lot of research done, and insects are very diverse, like there are so many different groups of insects, and
insects also have very different life stages. You know, they have larval stages, they have pupair stages, they have adult stages, and so really what you need is evidence for each of these different groups of animals at each of these different life stages and that is not there. But again, there is pretty good evidence for at least some groups
of insects that they do seem to meet these same criteria. Bees, for instance, are pretty well studied, and there's evidence that bees can make your flexible decisions, that they respond to painful stimuli.
Yes, if you can beleave it. Scientists have done experiments to test whether bees have consciousness. The experiment when something like this. They offered bees the option to drink sugary water from different feeding stations. Some stations had sweeter water than others, but all the feeding stations were rigged so that the pads the bees had to stand on to drink could get hot, hot enough to make it uncomfortable
for the bees to drink from that station. Now, when nothing was heated, bees would choose the sweetest stations, but when those stations were made to be hot, the bees would switch and drink from the less sweet feeding stations. Meaning the bees had to weigh the pros and cons of their options. Should I drink from the sweetest station but then it's kind of too hot, or should I go for a less sweet station even though I'm getting
less sugar? And this shows the scientists argue. In this case a biologist named Matilda Gibbons and her team that bees are doing something that resembles being conscious.
And so what she was looking at is again whether they could integrate that information on the risk of going to get the more sugard concentration based on the heat on their fate. At what point was it just not worth it?
In that case, they were weighing whether the buzz was worth it.
Yeah, I like what you do there, And it's sort of pointing to a sophistication in how they respond and make choices.
It's not a simple mechanism in their little brains. It's like they have to kind of think about it.
Yeah.
Yeah, And that's kind of the basis of the idea of sentience, is that they're thinking about things.
They're not reflexively responding. Like there's integration going on, there's weighing up, there's decision making.
According to doctor Brownie, bees have even been shown to potentially play, so.
Yes, a very cool work on bees recently showed that they seem to play for no other reason but can be explained except that they seem to like it. So if they get these little plastic balls that they can roll around. Even if those balls have got nothing to do with their food. You've never had anything to do with their food. You know, the food's in another room. The bees will still go and roll these balls around
for you know, decent periods of time. Really only explanation that the researchers can give is that they seem to be enjoying it, that this is something they like and it's fun for them, and so they do seem to be these little beings who can have these experiences of the world.
All right, at this point you may be wondering, well, well, what doesn't have consciousness? Well, it turns out people who study consciousness and animals do draw a line at some point. For example, the general consensus is that worms probably don't have consciousness. When you apply the same set of tests we've been talking about to worms, they score pretty low. They don't seem to have preferences or be able to weigh these complex decisions. And also plants, philosophers are fairly
sure they're not conscious, although not everyone agrees. You just put up an interesting point, which there plants, and I assume most people greep plants are not conscious.
Yeah, I think that is definitely the mailstream view. At the moment, there are people who think the plants are conscious, and I've seen some work of people arguing if plants are much more complex than I think we used to think they were, well communicate with one another. You know, trees have these massive underground root systems that no one really knew about before, where they can send chemical signals to one another, They can respond to different kinds of
environmental stimuli. But I think none of that passes the thresholds for what we would take in animals to be required for a conscious experience, okay, and particularly the speed of processing. So a lot of people think that in part what consciousness might be for is to help us respond relatively quickly to changes in the environment, to update what's happening to us, to be able to make decisions between competing motivations that we might have and plants they
don't move that kind of spilled. So one of the big things that differentiates an animal from a plant is that one part of the animal, right we're wanting to feed, an other part might be wanting to reproduce, and they can't do both those things at once. It has to pick one or the other. Whereas a plant is able to actually do multiple things at once. They don't have to physically move themselves around, and.
I see they don't have a sense of its whole being all at the same time.
Yeah, that's your right.
Okay. The last question we're going to ask about animal consciousness is what does it all mean? What does it mean that a dog has conscious thoughts, or that than octopus dreams, or that bees like to play. I asked both our experts this question. Okay, the last question, what are the implications of animals or certain animals having or not having consciousness or sentience?
So one sentience is recognized. I think humans are faced with ethical legal obligations.
When we think about how we act towards other animals. In my mind, whether or not they're sentient is the key feature that tells us whether or not we should be concerned about the harms that we're doing to them.
And I think that is profound because even if an animal, let's say a crab or an octopus, doesn't have an inner monologue, or they can't communimicate feelings or reason, it doesn't mean that they can't suffer, and so the ethical considerations of that remain critical. It means that their suffering counts.
I guess to get a little bit deeper, you said, it makes this these certain questions and responsibilities. What does that mean or why is that?
What it is? Is it? So being able to recognize that an animal has the capacity to feel negative and positive emotions, it removes this barrier of arpness, and so we could recognize that like us, like humans, they have this capacity, and so it bridges I guess, our world with theirs.
So studying consciousness and animals should make us think about how we treat them, and it can also tell us something about our own consciousness. What does that mean about our consciousness that animals are conscious?
Well, I think that a lot of research in the past has been like, well, this is unique to humans, and human intelligence and consciousness is highly complex, and we are able to obtain knowledge and understand concepts and thing can reflect in ways that we haven't been able to
see in other animals. But these things that pop up in our mind are not evolutionarily isolated, and so by recognizing and researching other animal minds, then forming a more comprehensive view of how the mind evolved in our evolutionary trade. Because each mind is one piece of the puzzle.
I see, we can trace where our consciousness came from, and that's a huge part of understanding what it is and how it works.
Yeah, exactly, all right.
We hope that made you a little more conscious of animal consciousness, so the next time you look at an animal eyes, you wonder what's going on in there. Thanks for joining us, See you next time you've been listening to Science Stuff. Production of iHeartRadio written and produced by me or Hm, predited by Rose Seguda, Executive producer Jerry Rowland, an audio engineer and mixer Ksey Pecrom and you can follow me on social media. Just search for PhD Comics
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