This is a panel, just like at a science fiction convention. Except that this convention was postponed due to a pandemic, and two of the panelists were not even planning on attending. Little problems like that are nothing in the science fiction future, so here we are. I’m the moderator — my name is Anna Davour, but please call me Åka. The discussion questions will be marked in bold to make it easier to follow what we are talking about. I’ll let the panelists introduce themselves.

Moderator: Who are you, and what do you like about spiders?

Peter Watts: I used to be a marine biologist; now I write SF. I like the way some spiders time-share cognition in their tiny little pin-brains with less than million neurons, so they can improvise, learn, and plan with an almost mammalian level of sophistication. The genus Portia is known in the biz as “the spider that thinks like a cat”. I like the way other spiders use their webs as a kind of brain augment, a network of logic gates that performs calculations when perturbed. It’s tragically ironic that the struggles of some trapped fly end up powering a mechanical computer calculating prey-acquisition parameters for the predator that’s about to eat it.

Mostly, though, I like the cute way some of them jump at your face when startled.

Torill Kornfeldt: I am a science journalist with a background in biology, I mainly write about gene editing but I love strange animals of any kind. And there is so much to love about spiders. I think one of the really interesting things about them that people have a tendency to forget is that some spiders, like jumping spiders, have figured out how to both have surround vision that lets them see in all directions but also have the focused, centered vision with — probably— depth perception that they need to be really effective as visually guided predators. They solve it by having eight eyes, two of which are movable to be able to focus.

Jessica Abbott: I’m an evolutionary geneticist who studies the evolution of sex differences and sex chromosomes. I mainly work on invertebrates. What I like about spiders is the same thing I like about insects — they do so many weird things. Spider silk is the most obvious example, but peacock spiders have amazing courtship displays, some spider females let their offspring eat them up to give them a good start in life, some spiders build huge social colonies with webs that span over several metres, and some live under water and make their own “diving bell” filled with air.

A couple of you mentioned jumping spiders. My daughter discovered something interesting about jumping spiders – they will chase a laser pointer light, just like cats. Biologically, this makes sense since they are visual predators. But it’s a fun experiment to try at home!

Adrian Tchaikovsky: I’m Adrian Tchaikovsky and spiders have pretty much shored up my career as an author so I like that about them very much. I used to have a whole complicated spiel about my use of insects, arachnids and similar invertebrates in my writing. I’d go on at length about Kafka and Pelevin and Capek’s Insect Play and how there was a long tradition of using insects as mirrors to human nature, all that literary stuff, but the truth behind all of that was that I have always liked insects. I used to doodle spiders on my homework and the teachers would tell me it’d never get me anywhere.

And yet there is a deeper truth behind that. I liked snakes and spiders and bats and insects as a kid, and I felt a kind of kinship with them because I was a weird disaffected little kid and they were animals that nobody liked, and that didn’t get all the PR of cats and dogs and birds and elephants and the like. It was an outsider thing, and spiders are probably the ultimate totem of the outsider because there’s no animal in the world more despised by more people than poor bloody spiders. Or at least that’s the case in Western modern cultures where – despite the general absence of actual dangerous spiders – they’re portrayed in almost universally negative terms.

Moderator: In the description of this panel I mentioned spiders and cephalopods. Why are we humans so fascinated by, and often scared of, these animals that are very different from us? Are there any other very alien creatures on earth that you would like to mention?

Jessica Abbott: Some evolutionary biologists have speculated that we have an instinctive fear of spiders and snakes since it’s adaptive to avoid poisonous animals. Although that’s possible, there’s obviously social or environmental effects as well. We learn to fear spiders through other people that are scared of them, or horror movies that make them out to be scary. I find them more interesting than scary, even though I don’t want to get bitten by a spider. Like most animals, they will usually leave you alone if you don’t disturb them. For some people a fear of spiders might lead to a fascination with them as well. But I would guess that most people who become fascinated with spiders usually do so because they learn something surprising about spiders and want to find out more.

There’s no obvious evolutionary reason why we should be scared of or fascinated by cephalopods. During human evolution it’s unlikely that we had enough contact with cephalopods to evolve any specific behaviour or instinct related to them. So the fact the we find them fascinating or scary is probably just a general reflection of the fact that we are often interested in things we don’t fully understand. There are lots of strange creatures on earth, but one of the things about cephalopods that’s particularly fascinating is that they are much more intelligent than we previously thought. That can’t be said of other odd animals like tardigrades.

Torill Kornfeldt: I think one reason is that they represent versions of more or less intelligent species that have evolved their cognitive abilities and their bodies in a completely separate way compared to us humans. We can identify with other mammals and to some extent understand both the needs and the visual signals from other animals — we can recognize and have empathy when a mouse or a deer is frightened, for example. We can even sort of understand birds and the occasional reptile. But cephalopods and spiders are completely alien to us.

Cephalopods are also animals who, despite being very intelligent, do not seem the least bit interested in communicating with us. Most other intelligent species are social and communicative, for example parrots or whales, but cephalopods couldn’t care less about us and I think that adds an extra layer of intrigue. The fact that it’s more or less impossible to figure out how you would keep track of eight legs or tentacles just adds to the charm of these groups.

Adrian Tchaikovsky: Torill notes that in their natural state cephalopods aren’t interested in communicating with us, which is true — they’re not much interested in communicating with each other, a lot of the time! — but in the lab they have come to recognise and actively interact with human individuals – I think it shows how very flexible their intelligence is, that they can step outside their evolutionary ‘comfort zone’ so readily – or perhaps that capacity is a necessary prerequisite for the kind of intelligence we’re looking for.

Peter Watts: To some extent, the fear might be instinctive: all spiders are venomous, for example, and the proportion that are dangerous to humans tends to be higher in the warmer climates our ancestors hung around in. In a more general sense, though, humans are frequently scared by things that are different from them because humans are fucking idiots.

But difference is also fascinating because it shows us novel and unexpected ways of doing things. Cephalopods do a lot of things differently than vertebrates — I mean, an octopus keeps two thirds of its nervous system in it arms. It’s been suggested that each one of those arms might be independently conscious, that there’s no such thing as an octopus because every individual is actually a colony (the central so-called “brain” wrapped around the esophagus might act as little more than a router). And yet, even with such a completely alien neural architecture, the Cambridge Declaration of 2011 includes octopuses among other more conventional creatures with “near-Human” levels of consciousness. Parrots were on that list too; it’s since turned out that although those guys may have relatively small kidney-bean brains next to us mammals, they also pack three times the neural density of mammalian brains. Once again, we humans overestimate ourselves and underestimate everything else.

Offhand, not much springs to mind on the “other very alien creatures” front. Deep-sea anglerfish with their extreme sexual dimorphism and dissolving parasitic males are pretty cool, not to mention nicely symbolic of the very concept of maleness, biologically. So are slime molds.

Adrian Tchaikovsky: As vertebrates, and especially mammals, dominate the land and, most especially, our cultural references — because the vast majority of large animals are vertebrates — invertebrates seem very alien to us. They move differently, they have more or fewer legs, their ‘faces’ have the wrong number of eyes and mouths that work in the wrong ways. Pet peeve: the giant spider illustration that can’t help giving the creature a horizontal vertebrate mouth, usually with teeth.

The other thing that they do – and I’m thinking particularly octopi, ants and spiders here, is that they are clever, or at least do clever things. Octopi are genuinely intelligent, ingenious creatures, undeniably skilled at problem solving and applying the prodigious toolkit that nature has given them in novel ways.

Peter Godfrey-Smith’s book Other Minds, which was invaluable reference for my Children of Ruin, goes into some detail about the ways octopi have surprised researchers, and to me the most remarkable one is that they are able to recognise individual humans, and form definite likes and dislikes about them. Which seems natural to us, because it’s what we do with each other, but octopi are not only a separate species with no common evolutionary territory, but a species mostly solitary in lifestyle. That ability to relate to humans is coming entirely out of their intellectual capacity rather than some pre-evolved instinct. And, though in this case it is evolutionary, ants excel at a number of aspects of life, from farming to war, that we would have preferred to hold as solely human affairs, and the one positive element spiders do hold onto is skill at crafting and weaving. Just as invertebrates come at locomotion and feeding by different routes, so they converge on human territory from unnerving and unique directions.

Moderator: By the way, how remote are our common ancestors?

Peter Watts: The lineage that gave rise to us split off from the line that gave rise to mollusks and arthropods about 700 million years ago, give or take. We’re actually more closely related to echinoderms than we are to either of those groups.

Ooooh, now there’s a weird bunch of life-forms. Echinoderms. Sea cucumbers vomit up their digestive systems as an antipredator strategy, and breath through their assholes — the technical term is “cloacal tree”. Sea stars walk on hundreds of hydraulic tube feet, each of which is semi-autonomous. So the tube feet don’t all move in the same direction; there are always some malcontents pulling against the majority. Starfish are kind of like the fleshly instantiation of True Democracy. Also they have no brain, which only strengthens the analogy. The upper surface of a sea star is stippled with these little claw-like things that keep the body clean of debris and infestation. And rip a starfish apart, each piece regenerates into a whole new organism so long as it contains a piece of the central disk. So, yeah. Echinoderms are pretty alien too, now that I think of them.

Adrian Tchaikovsky: So we diverge from most invertebrate lineages about 500 million years ago. In the Burgess Shale and other fossil lagerstatten dating back to the Cambrian explosion you can find animals that have been interpreted as proto-chordates, our ancestors, along with ancestors of all the major invertebrate lineages. It’s worth remembering that vertebrates rank alongside molluscs, arthropods and other big invertebrate groups – as far as Linnaean classification goes, it’s not vertebrates versus invertebrates as two equal branches.

Jessica Abbott: Humans and invertebrates like spiders and cephalopods are fundamentally different types of animals, and our last common ancestor was probably about 600 million years ago. Humans belong to the group called protostomes, which are characterized by a dorsal nerve cord — in our case, the spinal cord — and ventral gut. Spiders and cephalopods both belong to the group called deuterostomes, which are the opposite — they have a dorsal gut and a ventral nerve cord. So in terms of body plan, a spider is like a human flipped on its back or vice versa. Our last common ancestor probably looked like some sort of simple worm.

Margaret Atwood once famously said that science fiction is talking quids in outer space…

Peter Watts: Yeah, well, Margaret Atwood is kind of an idiot when it comes to defining genre, isn’t she? I even wrote an essay about that a while back.

Well, anyway, do you have any favourite examples of cephalopods, or beings similar to earth’s cephalopods in science fiction? What about spiders?

Peter Watts: Well, there’s always the “Triassic Kraken” — 30m long and possibly “the most intelligent invertebrate ever” — which ripped ichthyosaurs apart and arranged their bones on the sea floor in a way which “may represent the earliest known self‑portrait”. But since that hypothesis was presented during the The Geological Society of America’s 2011 conference, it doesn’t really qualify as “fictional”.

Moderator: Not entirely fictional perhaps — but the evidence doesn’t seem that solid to me, so I think we can classify it as fiction for the purpose of this panel.

Jessica Abbott: Cthulhu is of course iconic in the sci-fi/horror literature. But he’s not so nice so I don’t know if I’d call him a favourite. I’ve also ready a few different short stories with squid-like aliens – usually when speculating what intelligent life on ice planets similar to Europa could look like – but I don’t have a specific example that’s most memorable. So I guess my favourite sci-fi “squid” is Yivo in Futurama.

Torill Kornfeldt: Oh, there are so many examples of cephalopods and spiders in science fiction, from Chtulhu to Spider-man, that it is kind of hard to pick the best examples. I like the Scramblers in Peter Watt’s Blindsight, that kind of seem like a mix between spiders and octopi, and they are both highly intelligent and radically non-human when it comes to behaviour. I also kind of want to mention the amazing octopus that plays the drums in The little mermaid, and Ursula of course.

I have really been trying to think of nice or benevolent versions of these animals in fiction, but right now I can only remember the monsters. It’s a shame and I’m looking forward to hearing examples from everyone else.

Adrian Tchaikovsky: Well I’m going to blow my own trumpet and point at Children of Ruin, with the caveat that its spacebound talking cephalopods are originally of Earth stock, because of course that’s where cephalopods come from.

Another pet peeve: all those gabbling semi-science articles about octopi being aliens. They may have an intelligence alien to ours, but the cephalopod evolutionary history goes back just as far as ours does in the fossil record.

Similarly my spiders in Children of Time are just plain old Earth spiders, plus a lot of accelerated evolution. As non-terrestrial but very cephalodpodic aliens, though, the visitors in Arrival (based on Ted Chiang’s “Story of Your Life”) are visually superb, very alien, very visually striking.

Moderator: And what about spiders, where are your favourite spiders in fiction?

Peter Watts: That’s tougher. I’ve heard uniformly ecstatic reviews of the uplifted spiders in Adrian Tchaikovsky’s Children of Time but I haven’t read it yet so I can’t weigh in. The hibernating spideroids in Vinge’s A Deepness in the Sky were cool, but behaviorally they were presented as essentially humans in exoskeletons. Granted this was explicitly addressed as a necessary distortion to allow us to identify with them — their real mindsets were far more alien, we were told — but by that very token, the essential alienness was lost in translation. I might even cite the Portia entity in my own novel Echopraxia — it was explicitly named after an earthly spider, after all — but it was really more of an intelligent slime mold than an arachnid. The only spider-like characteristic was the time-sharing cognition trick.

Which leaves us with an old seventies-era movie called “Giant Spider Invasion”. A black hole crashes into a farmer’s field and disgorges a bunch of giant spiders. Apparently the main Giant Spider was a Volkswagen covered in bearskin rugs, with brake lights for eyes. I swear, during one scene when the spider was eating one of the characters, I saw the actor literally jump up into the spider’s mouth, and kind of slip and start to fall down until another arm reached out from between the mandibles and helped pull him back up to his grisly fate.

For the longest time I couldn’t remember whether I’d actually seen that movie or merely dreamed it. But Stephen King wrote about it in one of his nonfiction books. He loved it.

How can I not?

Jessica Abbott: When it comes to spiders, my favourite literary spider would have to be Charlotte from Charlotte’s Web.

Adrian Tchaikovsky: For spiders, I have a sneaky fondness for Shelob, even though Tolkien was an arch-arachnophobe. He hated spiders so much that he couldn’t even conceive of them being an intended part of Middle Earth, and so Shelob’s progenitor Ungoliant comes from outside the universe, and very nearly eats Sauron’s boss back in the old times. If that’s not a badge of merit I don’t know what is. In more recent works, Benedict Jacka had a positive spider oracle in his Alex Verus series, and of course there’s the Weaver from Mieville’s Perdido Street Station.

Moderator: If all mammals disappeared from the Earth, do you think some other of the planet’s intelligences would develop a complex, technological society?

Jessica Abbott: Maybe, but it’s not at all certain. There are plenty of simple organisms that are very successful without being intelligent according to any standard definition of the term, such as bacteria. Intelligence generally seems to be energetically costly since neural cells consume a lot of energy. That means that investing in a smart brain usually takes energy away from something else. For example, experiments with guppies have found that fish selected for large brains do indeed become more intelligent on average, but they also have shorter guts which means they are probably less efficient at digesting food. If being smarter means that you can get food more efficiently, then it might not matter that the smarter fish have shorter guts (this basically seems to be what happened during human evolution). But for high intelligence to evolve, it means that investing in brains needs to have a net benefit for very long periods of time. This is possible, but not inevitable.

Peter Watts: I’d put my money on the corvids or the parrots. They’re problem solvers; they build tools (as opposed to simply using them); they’re capable of syntax and grammar. Cephalopods — well, I’d love to see them rise to dominate the planet, but they’re solitary and short-lived (which doesn’t bode well for cultural transmission). Also the whole aquatic lifestyle puts a serious crimp in the odds of developing any tools based on metallurgy (although in an explicitly post-human scenario there could totally be chunks of refined metal lying around on the seabed, things that could be polished and sharpened. You might see a rudimentary technology built on repurposed salvage…)

It’s a shame, though, that you’ve posited the disappearance not just of humans but of all mammals, because I like to think raccoons might be decent candidates as well. They routinely outthink engineers. Here in Toronto we’re on our third generation of “raccoon-proof” organics bins, the latest and most sophisticated of which — as I can attest from personal experience — slows them up by maybe 30 seconds. Also they engage in cultural transmission. We’ve seen consecutive generations teach their kids how to open our screen door, for example. Although if there’s any evidence of linguistic skills, I haven’t read about it. Also they can’t disperse as rapidly as birds.

Odontocete cetaceans are smart, social, and persistently cultural, although their lack of prehensile appendages would seriously hold them back in the technology department. Unless they could telepathically enslave octopuses or someth—

Hey, now there’s a scenario. Dolphins have been known to use high-intensity sonar bursts to stun prey — basically an acoustic taser. They’re social, communicative, highly intelligent: so say they start using their attack sonar to bully octopuses into doing their bidding. Octopuses are smart and insanely prehensile, but solitary — so, chances of organized insurrection are pretty low, especially since their oppressors can literally eat them if they get out of hand. And their miraculous pattern-matching ability to blend in with the background is of limited utility against an opponent who “sees” using sound as well as light. Octopuses are smart enough to make and use tools even if every individual has to reinvent the wheel on their own, so it’s plausible that your average Pacific octopus would be able to figure out rudimentary commands: “grab that rock; bring me that crab”. So now you’ve got an intelligent social species using an intelligent solitary species as vicarious prosthetic hands…

Like I said. it’s a shame you got rid of all the mammals.

Torill Kornfeldt: There is something really compelling in the idea that civilisation and technology are somehow an inevitable result of evolution, and that obviously someone else would take our “place” if we disappeared. I don’t think that is true so I would say that the likelihood is really low. But it is fun to speculate, so let’s do that instead.

I think octopi would be the obvious choice — they are highly intelligent, good at solving problems in new ways and have arms to build things with. There has been some speculation (as Peter mentions) that technology can’t evolve under water because you would not be able to light fires — which are the first step in transforming metals and things around you. That might be human arrogance, although it would be interesting to see a technology not based on metals at all.

On land the easy choice would be corvids — ravens, crows and magpies. They are both intelligent, social and good at adapting to new circumstances and use the things we create to their own advantage, such as stealing fish from lines in northern Sweden. They could probably learn or evolve to handle fire, there are birds that wilfully spread wildfires to catch small animals. But without the dexterity of fingers or tentacles, it’s hard to see how they would start building advanced technology. Unless they start training lizards to do it for them.

Spiders would need to evolve a better breathing apparatus before becoming even more technologically advanced. Even if they are remarkably good at using their small brains, as Peter pointed out, they would probably need bigger brains and bigger bodies. Currently their size is probably limited by their breathing system and ability to get oxygen to all parts of the body so they would have to solve that first.

Adrian Tchaikovsky: So the spider evolutionary path in Children of Time is presented as mediated by a nanovirus, but that’s really only to contract the timescale into something plausible for the book. Given how remarkably complex and reactive their behaviour is, I genuinely think salticid spiders are a possibility for sentience, given a clear field and time to evolve.

Cephalopods are a much stronger bet given their existing cerebral prowess. The lovely spec evo show The Future Is Wild featured chimp-level arboreal cephalopods 200 million years in the future – in fact that whole show is just a cornucopia of wonderful speculation about future evolution. The major problem would seem to be sociability in species that are normally very solitary. However, social living has evolved multiple times independently in spiders, and there are the ‘octopus cities’ where they have ‘learned to get along’ with each other because the environment supports a dense population of them. As for other invertebrates, it’s a weird existential question as to whether hive insects — another social structure that has evolved multiple times independently — might give rise to intelligence – in Children of Time I went for ‘no’ and the ants basically become a gigantic predatory Babbage machine.

In Doors of Eden I kind of go ‘yes’ although the cockroach colony that results is very, very alien. Despite our own intelligence and success, we can’t say that those two characteristics are inexorably linked — and in the next century we may find that, in fact, the reverse is true. Life got on fine without intelligence or technology, and while it’s a flattering thought that intelligence is inevitable, and it’s a useful conceit for the SF writer to find intelligence wherever our fictional explorers go, it may be that intelligence isn’t the magic bullet to gaming evolution that we think it is. However, it is definitely more pleasing to conjecture that, if one de-spined the biosphere, we would have chitinous or tentacular successors, or even something stranger. Slime moulds cooperating to form a super-brain, maybe.

Moderator: What can we learn from the alien minds on Earth when we look for intelligent life in space?

Adrian Tchaikovsky: Another big philosophy question we can’t answer because we only have the one evolutionary history to study. On the one hand, there are only so many elements, only so many combinations of those support the sort of complex reactions life would — or might? — require, and their structure and polarities mean they come together to form certain molecules, and should do wherever you go. Hence the idea of alien life that is in some way like Earth life has some basis in logic.

On the other hand, that is a very Terra-centric view, and it’s possible that complex systems might occur and evolve in all manner of ways we can’t readily conceive of, involving non-Carbon ecologies, or even non-matter ecologies. I’m going to trumpet Stewart and Cohen’s book Evolving the Alien, also known as What Would an Extraterrestrial Look Like?, which is really good thought primer about the question. And of course if that’s true for the building blocks of life, sure any intelligence that arises out of an alien evolution would be more distant from us than even a housefly or a starfish in its view on the world.

If an alien could speak, we wouldn’t be able to understand it, as it were. Except, of course, the universe we share works in a certain way. There is an underlying structure of physics in place. It’s possible that, no matter the starting point, intelligence could converge because, once you begin to investigate and understand the universe, that’s bringing your mindset closer to any other sentience trying to understand the same universe, opening the door to meaningful communication between very different species. The fact that, as I mentioned above, the solitary and profoundly different octopus can relate to humans, recognise individuals and interact in an apparently meaningful way gives some hope that sufficient intelligence would suffice to overcome other differences, no matter how fundamental. Or that’s another humanocentric view, and it may be that being different means an alien, perceiving the universe, would see something very different to what we see, conceive of different truths, and never be able to reach out its finger-substitute, God to our Adam or vice versa.

Of course, all this presupposes the will to understand on both sides. I remember the octopus experiment where the researcher gave the octopus a bell cord to pull when it wanted attention. And then took it away again when the octopus used it to get attention, because it wanted too much attention. And octopuses are apparently notoriously difficult to experiment with because they don’t just obediently turn tricks for food like a rat or a dog might. They get bored, they dismantle things, they are temperamental. It’s the old problem that a nice simple model or behaviour is easy to model and measure and write up, but the easier it gets the less it tells us, until the actual intelligence is found only in the behaviours that don’t fit the experiment. If we’re to learn anything about alien intelligences from the intelligences here on Earth it’s maybe that our approach to studying intelligence might need a bit of a shake-up and a more qualitative approach.

Torill Kornfeldt: One thing we learn from alien minds on Earth is that intelligence can be really hard to recognize. All through history, and especially the history of science we humans have been terribly bad at noticing and recognizing the intelligence around us, even in the form of dogs, horses or cows – and those are animals that are not only mammals but specifically breed to be good ad communication with us and responding to our moods and thoughts.

We humans, in our hubris, seem to think that we automatically would have more in common with an alien that has developed technology than we have with donkeys or lions. But the opposite is more likely, and as long as we can’t have a proper conversation with a handful of different species here on earth, I don’t think we would recognize or be able to communicate with anything form outside earth.

Jessica Abbott: We are highly biased when it comes to estimating intelligence in other animals. Intelligence is actually very difficult to define, and we tend to think that animals that act like we do are more intelligent because we have an easier time understanding their intentions. This leads to practical difficulties in measuring intelligence in animals.

If we can’t find the right way to motivate an animal to solve a problem, then we might think it’s incapable of solving the problem and underestimate its intelligence. For example, the researchers who did the experiment with the guppies thought at first that only the females became smarter as a result of their increased brain size. When given a problem-solving task where the reward was food, the males didn’t seem to be able to figure it out. It turned out that the problem was just that the males weren’t really motivated by food. When they instead tested the males’ ability to find a female by solving a maze, it became clear that the large-brained males could find the female faster, meaning that they were more intelligent than the control fish. They just cared more about sex than food. The males’ motivation in this case isn’t even particularly difficult to understand, it’s just that using food rewards is a pretty standard procedure in animal cognition research, so the researchers tried that first.

We can therefore expect that there’s an inherent difficulty in measuring intelligence in organisms that are very different from us, since we will probably have trouble understanding what motivates them. I think that’s the most important thing we can learn from local species when looking for alien intelligence – it could be very difficult to recognize intelligence if the alien life forms have very different motivations than we do.

Peter Watts: If we knew what we were going to learn, we’d know it already. Unless you’re talking about mundane stuff like ‘Hey, how do you guys resolve particle/wave duality?’ or ‘why are you treating us the same way we treated every other — ohhhhhh…’, I think the stuff we learn will come as a complete surprise. Assuming we learn anything beyond that it’s impossible to really communicate with a truly alien intelligence.

There’s some grounds for optimism on that front. Assuming that the laws of physics are consistent throughout the universe, then evolution via natural selection probably is too. Which means that any naturally-evolved life forms we encounter will have been shaped by the same selfish-gene/inclusive-fitness algebra that shaped life here. There’s a basis for mutual understanding right there. If the aliens don’t have brain stems — if their thought processes aren’t rotten with cognitive biases that helped them survive by lying to them about the nature of reality — those artefacts will at least be part of their evolutionary history.

Let’s hope they’ve discovered how to weed that shit out. Now that would be something worth learning.

Moderator: “Intelligence is the ability to adapt to change”, as they say. But adaption takes different forms. What is it, in an animals and their environment, that stimulates what we (at least with some effort) recognize as intelligence?

Peter Watts: I don’t know who “they” are, but if they think “the ability to adapt to change” is a sufficiently exclusive definition of intelligence they’ve never met a Lentivirus (or conversely, a young-Earth creationist).

Moderator: I think this is one of those unattributed quotes that get thrown around, and no one knows who actually said it first. I have heard it so many times in the intro of a podcast that it’s stuck in my mind.

Peter Watts: Still, I’d admit that “change” does factor in there somewhere, and rapid change at that. The more stable and predictable the environment, the less the need for high intelligence. It’s not unreasonable to take home the message that intelligence arises from the need to improvise on the fly—to respond flexibly and rapidly to sudden environmental novelty.

Of course, over long enough timescales most “novelty” isn’t really novel; it either repeats itself and/or kills you outright. Seasonal variations, predator spikes—those sorts of changes can be dealt with via the brute-force intelligence of natural selection. (Apparently the periodic cicadas developed their 13 and 17-year underground nymph phases because prime-number emergence cycles are hard to sync up with if you’re a predator population. Sex evolved as a way to shuffle genes so that pathogens—which evolve faster than their hosts— would find it more difficult to get a target lock on immune systems. Those are both pretty intelligent strategies, if glacially slow in execution). The kind of environment that really drives fast intelligence is one that’s quick-witted in its own right: one that can respond to your responses in real time, one that can bootstrap an arms race. Which is to say, an environment in which the things you have to adapt to are intelligent in their own right.

So we’re talking either social conspecifics, or predators, or prey. I defy you to find a species on the planet that doesn’t fall into any of those categories. Which means the potential for bootstrapped intelligence is probably everywhere. Hell, even slime molds are problem-solvers.

So it all comes down to cost-benefit. The question is not whether an environment can “stimulate” intelligence; the question is whether such a stimulus is worth the considerable metabolic cost.

I wouldn’t hazard a guess as to what the threshold might be, though. Even in our own case, I’d say the jury is still out.

Torill Kornfeldt: This is a really tricky question. We humans tend to think that more intelligent is always better, but of course that is not the case for most animals. Intelligence is expensive and it doesn’t make you run faster or make your immune system better so you have to be in very specific circumstances for evolution to make it a priority. And we are not really sure what they are, but animals that we think of as intelligent have a few things in common. They tend to be predators or scavengers, with abilities to use a lot of different food sources under different circumstances. The other thing that many of them (but not cephalopods) have in common is that they have complex social groups, and have to keep track of evolving social dynamics between many individuals. They also tend to have somewhat long lives, so that knowledge and reasoning actually have time to pay off.

I don’t think they are the only situations where intelligence will evolve, but it seems to be a good starting point.

Jessica Abbott: I’ll summarize and add a bit to some of the things Peter and Torill have said. The things that have traditionally been considered most important are sociality, long lifespan, and being a predator, particularly in combination. Social animals need to keep track of the different individuals in their group, and how they should interact with each individual. For example, you might need to submit to a dominant group member, but dominate a subordinate group member, depending on your place in the social hierarchy. Many social species also engage in reciprocal behaviours, basically “I’ll help you if you help me”. This means that social species need to be able to remember and keep track of who they interacted with recently, and what the nature of the interaction was.

Predators are often expected to be smarter than their prey, since they may need to outwit the prey in order to capture it. This depends a lot on what sort of strategy the predator uses, of course. Species that simply sit and wait for prey to stumble over them don’t need to be particularly intelligent. Animal flesh is also more energy-dense on average than plant material, so eating other organisms can be a more efficient way to get the necessary energy to feed a hungry brain. The combination of sociality and being predatory seems especially favourable to the evolution of intelligence since many social predators hunt together and need to be able to plan and coordinate their actions in a complex way.

Long lifespan comes into the equation since it facilitates the evolution of learning. A very short-lived organism will probably spend most of its life in a relatively similar environment. All it then needs is a set of instincts that will provide the right behaviour for that environment. Of course, even species that we don’t usually consider to be particularly intelligent, such as insects, can show some evidence of associative learning. But the longer-lived an animal is, the more variable the environment it is likely to encounter, which means that it can be good to be able to try new things, as well as to remember and learn from previous experience. This favours the evolution of flexible problem-solving.

That being said, the cephalopods don’t really fit these general patterns. Many of them are predatory, but the most intelligent species are neither social nor long-lived. Researchers in cephalopod cognition have recently suggested that high risk of becoming prey yourself combined with a varied and challenging environment could be the key. These properties probably also favour the evolution of flexible problem-solving.

Adrian Tchaikovsky: Certainly social complexity seems to encourage intelligence. Octopuses excepted, apparently! If you have to keep track of complex relationships with neighbours, and if that contributes to your ability to survive and have offspring, then succeeding generations will become better at it. This is one reason why parrots and corvids, as Peter noted before, are so damn smart. It’s possible a varied diet would make one smarter, requiring more varied food-gathering strategies and behaviours – although that may go the opposite way, greater intelligence unlocking extra foods previously unavailable. I’ve also sometimes put forwards the idea that being in the middle of the food chain, simultaneously a predator and potential prey, is a good recipe for a bigger brain – not the cat-aliens and other top predators, but those who’ve evolved both to hunt and avoid being hunted – like Portiid spiders, and octopuses, and us.

In the end there’s only one hard rule. Intelligence needs to contribute to evolutionary fitness – not necessarily the fast-strong-tooth-and-claw sort of fitness that people often imagine, either. Greater empathy, greater sociability, recognizing conspecifics, reading their moods and working alongside them to accomplish greater feats than an individual could, these things can contribute to your success far more than being the big strong lone hunter.

If your lifestyle is that you just sit on the sea floor and syphon the water, intelligence is unlikely to help very much. If your bodyplan limits your ability to affect the world in any way, then likewise, In many scenarios, just getting smarter won’t necessarily bring any selective advantage. And, as Jessica says, it comes at a cost. Nothing’s free.

So in order to see where intelligence might flower, look for creatures whose mode of life and ability to influence the environment, and whose niche in their wider ecology, would make getting smart an advantage.

Moderator: What is the most fascinating thing that you have heard or learned about how other beings think?

Torill Kornfeldt: I think animals are consistently smarter and better at solving problems than we give them credit for, so it’s hard to think of an example. But I recently stumbled on some really interesting research on memory that might apply but humans and animals. It seems like the ability to forget unimportant details is very important when you want to learn and draw conclusions. The act of forgetting things might be both active and structured, so that we (or other animals, this is we in a very biological sense) can update with new information and also use things that we have learned in situations that are similar but not identical. This research is still quite new and changing rapidly, but I think some very interesting things are going to come from it soon.

Adrian Tchaikovsky: I’ve talked before about animals going out of their comfort zones. That always speaks of intelligence to me, as separate from ‘instinct’, which seems to be used to describe behaviours that are programmed in rather than arising from any kind of conscious decision-making (a very murky division). The solitary octopus that likes some humans and doesn’t like others is performing a task that seems to have no analogue in the world. The heron that strews bread on the water to attract fish. The parrot (Alex, in this case), that can actually use words with meaning and construct neologisms. The dog that can go fetch the toy, not from a photo of that toy, but from seeing the photos of all the others and working out which one’s missing from the set. And often we’re seeing gifted individuals here – the scientist who worked with Alex the parrot was never able to get another bird to the same level of interaction. But that shows the potential within a species, and in the wild such a gifted example of the species might contribute to the future of a gifted community, and thence to a whole new genius species in the fullness of evolutionary time.

Jessica Abbott: The thing that has become more and more obvious (and fascinating) for me the more I learn about animal cognition, is the importance of context. Animals evolve to be good at the things that are useful for them. They generally aren’t good at things that are not useful. Maybe this sounds trivial, but it means that animal cognition always needs to be seen through the lens of adaptation. For any specific task, there’s almost always some other organism that can do the task as well or better than a human, because it is an essential task for that species. Birds that store food for the winter can memorize the location of tens of thousands of hidden seeds, for example. Your average human is unlikely to be able to compete with this ability, but on the other hand we probably don’t need it.

Similarly, people often think that dogs are substantially smarter than cats, but this isn’t actually very clear. I mentioned motivation before. Dogs have been selected to be motivated to please us, and so it’s easier to carry out cognitive tests on dogs than on cats. Dogs have also been selected during domestication to become better at communicating with humans, and experiments with wolves raised in captivity show that they are considerably worse than dogs at understanding human body signals such as pointing. Cats probably haven’t needed these abilities as much, and therefore haven’t undergone as extensive selection to please us and communicate with us. Basically, it’s impossible to measure intelligence without having some sort of appreciation for what types of tasks an animal really needs to be good at.

Peter Watts: The most fascinating thing I have heard about how other beings think is probably the idea that Portia spiders, with their tiny pinpoint brains, can solve problems that would challenge mammals by partitioning their cognition. It’s an almost object-oriented way of thinking: use your limited resources to solve one part of a problem, scribble the solution onto a scratchpad, then throw out all your work and clear your brain to process the next module. Apparently, for example, the little guys can build up a remarkably high-resolution image of their surroundings in this way, an image far beyond what you’d expect from their measly little compound eyes (although it takes them hours to derive that model, as opposed to the seconds it would take a cat to scan the same vista). It’s been compared to taking in a room through a keyhole—you can see only a tiny fraction of the room at any given time, but by changing the parallax of your viewing angle you can scan back and forth and build up a detailed composite.

And it doesn’t just apply to vision. It lets Portia improvise behaviorally — change its strategy depending on angle of approach or how occupied its target might be with other distractions. It lets Portia figure out if it’s taken a wrong turn even if its destination isn’t line-of-sight.

It’s slow, but it gets there: a tiny mind emulating a bigger one piece by piece, a spider thinking like a mammal one laborious step at a time. What must that feel like? Does it feel like anything? Is there room for consciousness in any of those isolated slices of thought?

We may never know. (Although at least one peer-reviewed paper, to my knowledge, has argued that insects—and presumably arachnids as well— are “conscious” to at least some extent.)

Moderator: Is there something we have missed concerning alien mind on Earth, and that you would like to add?

Torill Kornfeldt: Not that I can think of, but I really want to thank the other panelists for a really interesting discussion. I have learned a lot and got a few new and really interesting perspectives on things.

Adrian Tchaikovsky: Between us, we’ve covered a great deal, but I think the lesson is that there is intelligence everywhere you look, and a large number of animals have behaviours far more complex, and arguably intelligent, than people have realized. For a long time, behavioural science had a horror of anthropomorphizing any description of animal behaviour, with the result being that animals were mostly described in mechanical terms.

There’s something of a renaissance going on, I think, in the field, where people are starting to attribute more volition and genuine intellect to animals, and once you start looking with a more open mind… well, just look at what the tiny Portiid spiders are capable of, object permanence and all. And we’ve not touched on tool use in animals – birds and primates and others, or in symbiotic relationships between species, which is a whole extra fascinating field – all those species that seem to have pets, for example, creatures they would normally eat but instead keep around to tidy the nest or what have you. There is, in short, just so much we don’t know. There’s complexity everywhere you look.

Thanks a lot for a very interesting and fun discussion! I hope to see you all on a real proper panel in front of an audience some day. Until then: stay safe and keep thinking about cool things.