Tuesday, June 17, 2014

Are bees intelligent?

The other day, Ken and I had coffee with a couple of philosophers who spend their time thinking about philosophy of the mind.  What is consciousness?  Do non-human organisms have consciousness?  What is intelligence?  How do we make decisions?  What about ants?  These are hard questions to answer, perhaps even unanswerable, but they are fascinating to think about.

Our meeting was occasioned by the recent paper in PNAS about the mental map of bees ("Way-finding in displaced clock-shifted bees proves bees use a cognitive map", Cheeseman et al.).  Cognitive maps are mental representations of physical places, which mammals use to navigate their surroundings.  Insects clearly have ways to do the same; whether or not they do it with cognitive maps is the question.

Honeybee: Wikipedia


The "computational theory of mind" is the predominant theory of how mammals think -- the brain is posited to be an information processing system, and thinking is the brain computing, or processing information (though, whether this is 'truth' or primarily a reflection of the computer age isn't clear, at least to us).  In vertebrates some at least of this takes place in the section called the hippocampus, or in non-vertebrates in some neurological  homologs.  But, what do insects do?  

Previous work has shown that captured insects, once released, often fly off in the compass direction in which they were headed when they were caught, even if they were moved during capture and the direction is no longer appropriate.  But, they then can correct themselves, and then have no problem locating their hives. That indicates that they've got some kind of an "integrated metric map" of their environment.

Some theories have held that they mark the location of the sun relative to the direction they take and then later calculate 'home' based on a computation of time and the motion of the sun.  This by itself would be a lot of sophisticated computing, or thinking....and why not 'intelligence'?

Cheeseman et al. asked whether instead what they are relying on is a series of snapshots of their environment, which enables them to recognize different landmarks, one after the other as they come into view, rather than a completely integrated mental map.  They experimented with anesthetizing bees and shifting their sense of time, so that they couldn't rely on the sun to get them home.  It took some flying for the bees to recognize that they were off-course, but they always were able to re-orient themselves and get back to the hive.

Cheeseman et al. conclude that that because bees don't rely entirely on a sun-compass for their sense of direction, they must have the apian equivalent of a cognitive map.  That is, they collect relevant spatial information from the environment with which they navigate, and use it to make decisions about how to get where they are going. That is, they take and file away snapshots; remember that insect eyes are complex, including two compound eyes and in most species three forehead-located small, simpler ocelli so this is synthesizing a many-camera pixellation and differently sensitive integration of the light-world. Then, they use a sequence of these frames, later, from a different position from that at which the photos were taken so not all landmarks might even be visible, and at a different time, which can affect shadows, colors, and so on.  Then, tiling these lined up in reverse order in mirror left-right flipped order somehow, and adjusting their angles of perspective and so on, also perhaps sound, wind direction, and even perhaps monitoring the olfactory trail (also in reverse relative position) like Hansel and Gretel's bread crumbs, they head home for dinner.

Two big compound eyes, and 3 simpler central ocelli. From http://169.237.77.3/news/valleycarpenterbees.html


To us, this is a remarkable feat for their small brains!  For some of us, even with a human brain, finding one's way home without a GPS is no easy task, and deserves a nice cold drink when done successfully.  However, the philosophers we were chatting about this with did not think what Cheeseman et al. believe they discovered about bees should be called a cognitive map because, and we think we've got this right, they haven't got a mental image of the entire lay of the land.  Instead it's as though they are connecting the dots; they recognize landmarks and go from one mental snapshot with a familiar landmark to the next. So what kind of 'intelligence' this is becomes a definitional question perhaps.  Call it mechanical or whatever you want, we would call this 'intelligent' behavior.

We don't know enough about philosophy (or the biology) of the mind to know how significantly these two models differ, or whether 'consciousness' is subtly underlying how these judgments about cognition are made, but in any case, that's not what interested us about the bee story.  What is the experience of being a bee?  Whichever kind of imaging and processing they do to navigate, how do they turn the locational information into action?  It's one thing to know that your hive is east (or the apian equivalent) of the pine tree, but getting there requires "knowing" that after you've collected the nectar, you then want to bring it home, and that means you have to find your way there.  Your mental map, whatever it consists of, must be made operational.  How does that happen, in a brain the size of a bee's? Or an ant's?




Or bird brains?  Crows, corvids, are considered among the smartest of birds.  Their problem solving skills have been documented by a number of researchers, but crows have fascinated many non-scientists as well, including our son, who sent this observation from Lake Thun in Switzerland.
Crow found a little paper cup with some dried out dregs of leftover ketchup in the bottom. This is the sort of little paper condiment cup that would come with some french fries. We watched the crow try a couple of times to scrape some ketchup out with his beak, holding the cup down with his foot. It apparently wasn't working enough to his satisfaction, so he flew with the cup to the edge of the water (we were at the lake). He wanted to get the ketchup wet to "hydrate" it, to make it easier to scoop out. That was impressive enough, but what he did next was even more. There were little waves lapping on the "shore" (this was actually in a harbour and the shore was concrete) and each time threatening to carry away his cup. So he picked up the cup and carried it along up and down the shore until he found a little crevasse in the concrete that he could secure the cup, and let the water wash over it without taking it away. Clever.
If that's not intelligence, it's hard to know what it is, then.

One view of intelligence is that it's what's measured by IQ tests.  Or, at least, what humans think 'thinking' is all about.  But this is perhaps a very parochial view.  We tend to dismiss the kind of intricate brainwork that is required by nonverbal activities, or by athletes, or artists, or artisans.  We tend to equate intelligence with verbal kinds of skills measured on tests devised by the literate segments of society who are using the results to screen for various kinds of western-culture activities, suitability for school, and the like. There's no reason to suggest that those aspects of brainware are not relevant to society, but it is our culturally chosen sort of definition.

Philosophers and perhaps most psychologists might not want to credit the crow with 'intelligence', or they may use the word but exclude concepts of perceptual consciousness--though whether there are adequate grounds for that that are not entirely based on our own experience as the defining one, isn't clear (to us, at least).  In any case, wiring and behavior are empirically observable, but experience much less so, and consciousness as a component of brain activity, and perhaps of intelligence, remains elusive because it's a subjective experience while science is a method for exploring the empirical, and in that sense objective world.

If bees and, indeed, very tiny insects can navigate around searching the environment, having ideas about 'home', finding mates, recognizing food and dangers, and they can do it with thousands rather than billions of neurons, at present we haven't enough understanding of what 'thinking' is, much less 'intelligence', to know what goes through a bee's or a crow's mind when they're exploring their world....

13 comments:

Kenny A. Chaffin said...

Excellent post. Thank you. Shared on G+

Manoj Samanta said...

http://globaleconomicanalysis.blogspot.com/2013/02/can-you-beat-chimpanzee-in-memory-test.html

Anne Buchanan said...

Amazing. But I don't buy the evolutionary explanation -- why would we have lost the ability, if it's 'for' assessing dangerous situations or finding food?

Bones and Behaviours said...

Why would most psychologists not credit crows with intelligence? Crows and other birds actually are assessed by psychometrics. For such measures to apply to crows they must have intelligence as is normally defined.

As for Manoj's link about the chimps, it would be interesting to see whether hunter foragers have higher memorisation skills than ours. Out in environments such as the Aussie outback or the Kalahari I'd expect memory to be much more important for human survival than it is for us.

Ken Weiss said...

I personally think the issue is semantic and ultimately boils down to whether one thinks the organism is 'aware' or 'self-aware' or, basically, 'conscious'. If that is the issue about what is 'intelligent', it is really a matter of definitions that we currently have no way to test in terms of whether they mean what we think they mean....and they mean different things to different people.

Bones and Behaviours said...

It is true that the concept of intelligence is ill-defined, but I think you are overstressing the role of sentience in typical psychological constructs of intelligence.

I think I know what you're thinking of, its the kind of subject at the heart of Watts' Blindsight. Intelligence without the 'awareness' we take for granted, right?

http://www.rifters.com/real/shorts/PeterWatts_Blindsight.pdf

Ken Weiss said...

I knew of but have not read the book, but I think that's the general issue. We personally are not knowingly over-stressing sentience in that we are simply fascinated by the idea of problem-solving ability and purposiveness, or 'intelligence', without self-awareness and (to me) it's because we can't personally experience it very well, though we know we can drive our car and so on without explicit conscious awareness. In people we often have discussions with, one issue is whether animal food species are sentient and whether there is an ethical issue about how we treat or kill them. Maybe among psychologists these things are not a problem.

Bones and Behaviours said...

I wouldn't say they're not a problem to psychologists, but they relate more to bioethics than to psychology because, as you say, its hard to operationalise something so internal whereas ethicists must use psychology to infer their conclusions, even from poorly defined and easily abused constructs. The well-known mirror test for example fails, because psychopaths can self-recognise in a mirror yet lack other aspects of self-consciousnes such as internal dialogue (something that sounds to them as though it is schizophrenia or demonic possession.)

In bioethics the fuzziness of consciousness gets abused so as to justify just about any ethical appeal. Its quite clear that when deciding upon the most ethical treatment of animals, separate standards and criteria are accidentally on purpose chosen to make a 'side' look more scientifically correct. Its hard not to be cynical when people talk about 'consciousness' even though there exists demonstrable difference between general anaesthesia and full awareness, and I wish it would be downplayed a bit more in ethics.

Ken Weiss said...

To me we are SubjectiveLand, where terms people use may be as important to discussion as the substance, and hence not much discussion and probably lots of miscommunication.

Andrew said...

I thoroughly recommend Louise Barrett's book 'Beyond the Brain' for a more embodied analysis of animal (and human) intelligence. The field is moving away from computational, representational models and towards a more dynamical systems embodied approach, and her book is an excellent place to begin if you're interested in this topic.

Anne Buchanan said...

Thanks very much. This is good to know.

Unknown said...

Any chance you could help with access to the cognitive map article?

Anne Buchanan said...

The PNAS paper? Sure, let me know where to send it. avbuchanan at gmail