Animal Magic: Why Intelligence Isn’t Just for Humans
Meet the footballing bees, optimistic pigs and alien-like octopuses that are shaking up how we think about minds.
How
do you spot an optimistic pig? This isn’t the setup for a punchline;
the question is genuine, and in the answer lies much that is revealing
about our attitudes to other minds – to minds, that is, that are not
human. If the notion of an optimistic (or for that matter a pessimistic)
pig sounds vaguely comical, it is because we scarcely know how to think
about other minds except in relation to our own.
Here is how you
spot an optimistic pig: you train the pig to associate a particular
sound – a note played on a glockenspiel, say – with a treat, such as an
apple. When the note sounds, an apple falls through a hatch so the pig
can eat it. But another sound – a dog-clicker, say – signals nothing so
nice. If the pig approaches the hatch on hearing the clicker, all it
gets is a plastic bag rustled in its face.
What happens now if
the pig hears neither of these sounds, but instead a squeak from a dog
toy? An optimistic pig might think there’s a chance that this, too,
signals delivery of an apple. A pessimistic pig figures it will just get
the plastic bag treatment. But what makes a pig optimistic? In 2010,
researchers at Newcastle University showed that pigs reared in a
pleasant, stimulating environment, with room to roam, plenty of straw,
and “pig toys” to explore, show the optimistic response to the squeak
significantly more often than pigs raised in a small, bleak, boring
enclosure. In other words, if you want an optimistic pig, you must treat
it not as pork but as a being with a mind, deserving the resources for a
cognitively rich life.
We don’t, and probably never can, know
what it feels like to be an optimistic pig. Objectively, there’s no
reason to suppose that it feels like anything: that there is “something
it is like” to be a pig, whether apparently happy or gloomy. Until
rather recently, philosophers and scientists have been reluctant to
grant a mind to any nonhuman entity. Feelings and emotions, hope and
pain and a sense of self were deemed attributes that separated us from
the rest of the living world. To René Descartes in the 17th century, and
to behavioural psychologist BF Skinner in the 1950s, other animals were
stimulus-response mechanisms that could be trained but lacked an inner
life. To grant animals “minds” in any meaningful sense was to indulge a
crude anthropomorphism that had no place in science.
Some caution
was warranted. If other animals behave like us, that’s no basis to
assume that they do so for the same reasons and with the same
experiences and mental representations of the world. But as countless
careful experiments like this study of pigs reveal ever more about the
inner world of animals, there comes a point where it looks far more
contrived to suppose that their behaviour just happens to look like ours
in all kinds of ways while differing utterly in its explanation. Maybe,
instead, they have minds that are not really so different after all.
Primatologist Frans de Waal warns that, while we must avoid
anthropomorphising other animals such as great apes, sometimes their
actions “make little sense if we refuse to assume intentions and
feelings”.
After all, as Charles Darwin pointed out, we all share
an evolutionary heritage – and there is nothing in the evolutionary
record to suggest that minds were a sudden innovation, let alone that
such a thing occurred with the advent of humans. “There is,” Darwin
wrote in The Descent of Man, “no fundamental difference between man and
the higher mammals in their mental faculties”.
The challenge,
then, becomes finding a way of thinking about animal minds that doesn’t
simply view them as like the human mind with the dials turned down: less
intelligent, less conscious, more or less distant from the pinnacle of
mentation we represent. We must recognise that mind is not a single
thing that beings have more or less of. There are many dimensions of
mind: the “space of possible minds” (a concept first proposed in 1984 by
computer scientist Aaron Sloman) has multiple coordinates, and we exist
in some part of it, a cluster of data points that reflects our
neurodiversity. We are no more at the centre of this mind-space than we
are at the centre of the cosmos. So what else is out there?
Consider
the often maligned bird brain. Compared with bird neurodiversity,
humans are a monoculture. Birds’ minds are scattered widely in
mind-space, their differences and specialities tremendously varied. Some
birds excel at navigation, others at learning complex songs or making
elaborate nests. Scrub jays are expert food storers, able to stash
hundreds of caches around their habitat and find them all flawlessly,
returning first to the most perishable items. They are cunning: cache
thieving is common, and the birds might employ deceptive measures such
as returning soon after depositing a store to move it to another
location – but only if they know they were observed while caching it. Or
even more remarkably, pretending to do so, suggesting that they have
what psychologists call a “theory of mind”: the capacity to acknowledge
the existence of other agents with motives and knowledge different from
their own. (Human children only acquire this around the age of three or
four.) In contrast to the common view that other animals live in a
perpetual present, scrub jays may store food in anticipation of the
circumstances they are likely to face later: experimenters found that
they will do this when placed in a cage that the birds know from
experience is likely to contain no food tomorrow.
We award pride
of place in the hierarchy of bird minds to tool-using species,
especially corvids (crows, ravens, rooks). The most masterful of them is
the New Caledonian crow of the south Pacific, which will design and
store custom-made hooks for foraging, and even make tools with multiple
parts. Among animals, great apes, dolphins, sea otters, elephants and
octopuses are the only others known to use tools. The challenge is to
figure out which qualities of mind corvids bring to bear on the task.
Young children acquire an “intuitive physics”: they understand that
objects don’t simply vanish, that they have properties like hardness and
brittleness, and (eventually!) that cups that are tilted or
precariously balanced may topple. They become able to execute multi-step
tasks, keeping the end in mind at each stage.
It’s not yet clear
what the “rules” are that govern a bird’s ability to deploy a tool.
There’s a distinction, for example, between “ritualistic” and
“mechanistic” thinking: “if I move the stick like this, bugs appear”
versus “the stick pokes out the bugs”. Generally you need the latter
view to adapt tools to new uses. You need a basic grasp of cause and
effect.
We’re gradually teasing out what bird behaviour reveals
about the way they represent the world internally: to what extent they,
like us, can deduce the possibilities and affordances it offers for
achieving goals. What’s harder to determine is how all this feels for
the bird. It was long assumed that the anatomy of the bird brain
(lacking a neocortex) is too different from ours to support any
conscious experience, but recently those differences have been found to
be less pronounced. How do you test, though, if another animal has a
sense of self? One approach is to see if it shows an ability to assess
its own state of knowledge: can a bird “look into” its own mind and
acknowledge what it doesn’t know? Recent experiments with crows suggest
they can.
If we’ve sometimes been ungenerous to birds, bees and
other insects were often seen as the epitome of mindless automata
blindingly following programmes. Naturalists in the 18th century
suggested that bees execute the perfect geometry of comb-building by
“divine guidance and command”; today we recognise that this exquisite
hexagonal mesh demands only that each bee follow simple construction
rules. Hive-building is, then, no more a sign of advanced rationality in
bees than chess-playing is in humans – there, computers can defeat us
with not a glimmer of sentience.
Football, however, is another
matter. Lars Chittka of Queen Mary University of London and his
colleagues have trained bees to manipulate a small ball into a hole at
the centre of the “pitch” for a sugary reward. Bees can train one
another in the task, and can find better solutions than their
demonstrator: they don’t blindly follow rules but adapt them to the
circumstances.
Although animal communication can be subtle and
complex, it’s generally thought that no animal besides a human uses
symbolic communication, where one concept is represented by another, as
it is in writing. None, that is, except perhaps the honeybee, which
conveys information about a distant food source to its hive members by
dancing. The bee treads out waggling movements on the comb, and watchers
deduce the distance to the source from the number of waggles, and the
direction to the source from the orientation of dance relative to the
downward arrow of gravity. It sounds like a weird problem in a geometry
exam, requiring protractors and conversion of units: “If each waggle
equals 10 metres … ” and so on. The waggle-dance code even has regional
dialects that might take into account the local terrain. And each bee
interprets the instructions in the light of its own internal map of the
surroundings, gathered and refined by previous forays. All this happens
in a bee brain about the size of a large grain of sand.
There may
even be such a thing as an optimistic bee. The equivalent of the pig
experiment uses flowers: blue ones carry a sugar reward, green ones
don’t, but will a bee interpret an ambiguously blue-green flower
optimistically or pessimistically? Again, behaviour seems to be coloured
by experience: bees that have just been given an unexpected sugar treat
seem more inclined to optimism, as though put in a good mood. Again, we
can’t know if the behaviour is accompanied by a “feeling” – but
machines don’t do stuff like this.
Time now to journey further
afield in mind-space. Philosopher Peter Godfrey-Smith says that the
octopus is “probably the closest we will come to meeting an intelligent
alien.” Octopuses interact with us, apparently with neither fear nor
aggression. But in contrast to a dog or a chimpanzee, it’s hard to
fathom what the agenda might be. They are great problem-solvers: they
unscrew jars, navigate mazes in the murky gloom of the seabed, and fuse
bright laboratory lights with jets of water. They seem playful – but who
knows, really, what the antics are for?
If this is perplexing,
we should hardly be surprised. Our evolutionary lineage diverged from
that of octopuses (which are molluscs) around the dawn of complex
multicellular life 600m years ago; our common ancestor was a mere
flatworm. So octopuses represent an entirely distinct evolutionary path
to making a mind – and how different it looks! The octopus has a similar
number of neurons as a dog, but instead of being mostly collected in a
central brain they are distributed throughout the body in a ladder-like
network. There is a centralised brain in the head, but more than half of
the nervous system is in the arms, gathered into clusters called
ganglia that seem to operate largely autonomously: the arms do things of
their own accord while the brain watches, perhaps as if observing
another creature.
If there is any kind of consciousness in the
octopus mind – thanks to the advocacy of marine biologists and other
experts, they were recently admitted into the category of sentient
beings under UK law – it might not be unified. Some researchers suggest
that octopuses have dual or even multiple consciousness: each individual
creature might be a loosely integrated community of minds. “When I try
to imagine this,” Godfrey-Smith says, “I find myself in a rather
hallucinogenic place.”
Even this, however, might sound tame
compared to the idea that plants have minds. Yet that proposition is no
longer confined to the fringes of new-age belief; you can find it
discussed (relatively) soberly in august scientific journals. There, it
often goes by the name of “plant neurobiology” or, in a more extreme
form, “biopsychism” – which supposes that every living being from
bacteria up has sentience of a sort.
Plants don’t have a nervous
system, or even neurons. But their cells, like many non-neural cells, do
communicate with one another electrically, and there’s evidence that
cellular channels in plants called phloem can transport not only sugars
but also electrical pulses. Some plants show distinctly animal-like
behaviour: witness the carnivorous jaws of the Venus flytrap, which even
displays a primitive ability to “count” the number of impulses it
senses before closing on an insect.
Plants can sense and respond
to stimuli, as when flower heads move to track the progress of the sun
across the sky. The South American “sensitive plant” Mimosa pudica, a
member of the pea family, folds its leaves when touched and displays a
kind of learning called habituation, where it eventually ignores a
repeated stimulus that proves harmless. Pea plants can be trained in an
almost Pavlovian fashion to associate a neutral signal such as the flow
of air with a beneficial signal such as light.
All this justifies
a view of plant behaviour as “cognitive”. Where it becomes more
controversial is in suggestions that the plant behaviours are
accompanied by sentience or feeling. On that, arguments still rage.
Conceiving
of a universe of possible minds can discourage human hubris, and
advises erring on the side of generosity in considering the rights and
dignity of other beings. But it also enables a literally broad-minded
view of what other minds could exist. Mindedness needn’t be a club with
rigorously exclusive entry rules. We might not (and may never) agree
about whether plants, fungi or bacteria have any kind of sentience, but
they show enough attributes of cognition to warrant a place somewhere in
this space. This perspective also promotes a calmer appraisal of
artificial intelligence than the popular fevered fantasies about
impending apocalypse at the hands of malevolent, soulless machines.
There is no reason to suppose that today’s AI has any more sentience or
experience than the rocks from which its silicon is extracted. But it,
too, shows intelligence of a kind, including the ability to learn and
predict.
To suppose that something like artificial consciousness
will emerge simply by making computer circuits bigger and faster is, as
one AI expert put it to me, like imagining that if we make an aeroplane
fly fast enough, eventually it will lay an egg. Computers and AI are
taking off in the “intelligence” direction of mind-space while gaining
nothing on the “experience” axis: their trajectory is heading not
towards us but somewhere else entirely. If we want AI to be more
human-like, many experts believe we will need explicitly to build human
qualities into it – which in turn requires that we better understand
what those are and how they arise.
Likewise, most of our
fantasies about advanced alien intelligence suppose it to be like us but
with better tech. That’s not just a sci-fi trope; the scientific search
for extraterrestrial intelligence typically assumes that ET carves
nature at the same joints as we do, recognising the same abstract laws
of maths and physics. But the more we know about minds, the more we
recognise that they conceptualise the world according to the
possibilities they possess for sensing and intervening in it; nothing is
inevitable. We need to be more imaginative about what minds can be, and
less fixated on ours as the default. As the biologist JBS Haldane once
said: “The universe is not only queerer than we suppose, but queerer
than we can suppose.” Our only hope of understanding the universe, he
said, “is to look at it from as many different points of view as
possible.” We may need those other minds.
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