Why consciousness??
January 25, 2006 7:43 AM   Subscribe

Why did consciousness evolve?

I was inspired by this quote of Kurt Vonnegut's:

"I was taught that the human brain was the crowning glory of evolution so far, but I think it’s a very poor scheme for survival."

I think Vonnegut's comment extends to the realm of consciousness in general. Why did evolution happen to move in the direction of conscious reflexion when there are surely simpler, more efficicent ways to aid an organism's survival?

Expansive answers more than welcome...
posted by 0bvious to Science & Nature (38 answers total) 3 users marked this as a favorite
Evolution is not good at answering "why" questions, beyond solving a problem at hand, generation by generation, namely surviving and reproducing better than the other guy.

We could have evolved with a heart on the right side of the body, for example, but this would have required rewiring of many developmental processes that evolved over millenia. Once a process gets started, it's hard (very low probability) to suddenly go another direction. Whatever consciousness is, it's the end product of a lot of accumulated changes.

Beyond the problem of defining consciousness and cognition, a very convoluted and dense subject that scientists are only beginning to figure out, the bottom line is that, whatever it is, it evolved because it helped us propagate.

Other organisms (insects particularly) have evolved biochemical means of communication, for example, and do very, very well as a species. "Consciousness" is only one way of solving the puzzle of survival and propagation.
posted by Rothko at 7:54 AM on January 25, 2006

As part of my answer, I'm going to modify your question somewhat.

Why did human evolution happen to move in the direction of conscious reflexion when there are surely simpler, more efficient ways to aid an organism's survival?

Well, considering all the different evolutionary changes possible in organisms, it was bound to happen to some species sooner or later. Considering the vast number of species lacking (apparent) conscious reflection, I'd say it's evolutionarily more advantageous to be without it on a grand scale. But obviously under certain conditions conscious reflection can have its advantages as well.
posted by GhostintheMachine at 7:55 AM on January 25, 2006

Why did evolution happen to move in the direction of conscious reflexion when there are surely simpler, more efficicent ways to aid an organism's survival?

It's not an either/or question. Many, many forms of life thrive without "consciousness" as you mean it. That's one thing to note about evolution. It doesn't have a "bottom" and a "top" with us at the top and worms at the bottom. What evolution has done is spawn a vast diversity of viable lifeforms. We are just one of them, not some kind of "pinnacle" of evolution. Branching bush, branching bush.....

I'd say that language and its ability to pass information between generations is a pretty huge quantum leap in survival advantage. If you are talking less about congitive skills and more about "awareness that you are aware" then I don't know what to tell you. I think everything is aware of itself in its own way. It's impossible for us to know what that is for a worm, so I wouldn't even start with the premise that we've got anything special going on.
posted by scarabic at 8:05 AM on January 25, 2006

I suppose you could build a chain of causes...

Consciousness is a useful upgrade for a big brain.

A big brain is a handy thing to have if you have opposable thumbs to manipulate the world with.

Hands are neat things to develop if you're spending a lot of time on two legs.

If you've been forced from the forests onto the savannah, you'll spend a lot of time standing up looking for predators.

I'm just riffing on Rothko's answer here, really. The thing about evolution is that you can always find "causes", but nobody knows for sure.
posted by Leon at 8:07 AM on January 25, 2006

consciousness is the byproduct of an ever increasingly advanced nervous system which has been quite useful for finding creative solutions to our particular history of survival problems. no doubt we have had a certain amount of luck in advancing the quickest, altho vonnegut's cynicism is well taken.
posted by paradroid at 8:12 AM on January 25, 2006

This is a tricky one, because although the line between neuroscience and philosophy has grown blurry, there's still a difficulty on either side to pin down what constitutes consciousness, and an even greater difficulty in translating one to the other.

Gerald Edelman is one of the most noteworthy people to write on the biological theory of consciousness: his Bright Air, Brilliant Fire is a great place to start.
posted by holgate at 8:14 AM on January 25, 2006

What's a more efficient way to aid an organism's survival?

People may very well end up destroying all life on earth, but then again they may end up colonizing the galaxy. Maybe we'll nuke each other sterile, but then again maybe we'll stop an asteroid from cracking the planet open like an egg. The brass ring is that some day we'll have arbitrary control over nature, genetics, even physics, and that's something you can only get through consciousness. There's a staggering number and variety of beetles in the world, but they're of extremely limited potential.
posted by Hildago at 8:16 AM on January 25, 2006

if not, then who is asking the question?
posted by paradroid at 8:27 AM on January 25, 2006

The thing to remember about evolution is that the cause and effect are sort of backwards. We didn't evolve to stand on two legs because we needed to be taller (to see the lions on the plains), but rather, some people happened to be taller and those are the ones that survived, because they could see the lions on the plains.

With consciousness comes the ability to plan ahead and solve problems in a more adaptable manner than "instinct" provides. It could be argued that, for instance, squirrels are not conscious in the way that we are, but they have "instinctual" planning ahead facilities. Which is to say that they have an ingrained proclivity for hording nuts. And it seems to have served them just fine. But, what if there are no nuts one year? Squirrels die is what.

So, up to a point, people that were smarter and managed to plan ahead a little better were more likely to survive and were probably more attractive as mates. As evidenced by reality TV (wife swap, anyone?) the smartness requirements for survival are less stringent than you might at first imagine. And self awareness certainly doesn't seem to be a requirement of any sort (super nanny, anyone?).

Consciousness itself is very likely a by-product of other abilities and traits, and not evolutionarily useful in it's own right.
posted by jaded at 8:34 AM on January 25, 2006 [1 favorite]

It's probably just a side-effect.

But if you break it down, consciousness can be looked at nothing more then the mind's ability to analyze itself, to think about it self. It would be weird if the consciousness did not exist, because that would mean evolution would have to remove the ability to think about one particular object -- itself. Arguably thinking about the body (and the brain) are the brains most important jobs.

The human brain is very good at asking questions of itself, and then thinking about what the answer might be.

Think about it this way. There are two humans running around in the jungle. You and your girlfriend. She likes a particular kind of fruit. Your brain starts to model her and you can predict that she'll eat it. Then you notice that You don't like it, and start to ponder wtf this "you" thing actually is.
posted by delmoi at 8:35 AM on January 25, 2006

if not, then who is asking the question?

Why do you need to be conscious to ask a question? You can write a computer program that can analyze a database for missing data, and inquire about it. Is such a program 'conscious'?
posted by delmoi at 8:36 AM on January 25, 2006

Consciousness itself is very likely a by-product of other abilities and traits, and not evolutionarily useful in it's own right.

That's what I was going to suggest. Although I have no meaningful qualifications in this area.
posted by ludwig_van at 8:44 AM on January 25, 2006

if not, then who is asking the question?

this comment is not meant in the mechanical sense, but rather philosophically. without consciousness there is no intentionality.

one suggestion for the usefulness of consciousness is that it has facilitated culture, as described by memetics, which has served to accelerate the process of evolution.
posted by paradroid at 8:52 AM on January 25, 2006

I think this the idea that the human brain (or a component thereof) is a "very poor scheme for survival" is pretty clearly disproved -- we've done pretty well for ourselves. And I think it's indisputable that it's because of our brains and not our brute strength or agility or well-adapted camouflage or anything like that.
posted by BaxterG4 at 8:59 AM on January 25, 2006

You might be interested in some of the research done by Robin Dunbar on social group size in primates (including humans). Also in the theory of Machiavellian Intelligence.

Dunbar has come up with the idea of a number for each species of primate which indicates the maximum number of people that they can interact with socially. With humans this works out at something comparatively large - about 150 individuals.

Machiavelian intelligence is about the ability to behave on the basis of judging how others in our group may be thinking - for example by making aliances, lying, etc. Other primates have been shown to do this.

So there is an argument that humans evolved to live in fairly large groups at about the time when climate warming in Africa meant that their habitat became more like a savannah with food spread out (apparently all primates that eat fruit also live in larger groups). If the ability to live in a larger group conferred a sufficiently strong evolutionary advantage then there may have been an associated pressure to become good at working out what others were thinking. One good way of doing this is to be conscious oneself.

Wikipedia have a large collection of links about consciousness - some of the neurophysiological studies are particularly interesting.
posted by rongorongo at 9:10 AM on January 25, 2006

A controversial thesis: "The Origin of Consciousness in the Breakdown of the Bicameral Mind" by Julian Jaynes."
posted by ericb at 9:10 AM on January 25, 2006

Well, this is a huge question. As you can see in this thread, there are lots of different "positions" on consciousness. There are "skeptics" like delmoi who argue that consciousness doesn't exist; they're opposed by philosophers like John Searle and other "naturalists" who argue that it (obviously) does. Then there are "anti-materialists" and "cognitive pessimists" who argue that consciousness is beyond the material world, or that there is an "explanatory gap" that we will never be able to bridge in talking about it, respectively. And then there's a debate about whether consciousness is instrumental and important, or just an "epiphenomenon." These epiphenomonalists go back all the way to the 19th century, when Thomas Huxley suggested that consciousness was like the steam whistle on a locomotive. John Searle (I think) recently formulated this quite well: maybe consciousness is like the sunlight reflecting off the ripples in a pond.

Personally, I throw my lot in with the naturalists. While I take delmoi's point, I think it has the same problem as philosphical solipsism (the "brain in a vat" hypothesis), which is that the vast proponderance of anecdotal evidence is against it. And I don't even understand what it would mean for "me" to be under the illusion that "I" exist. This seems to me to be an outcome of what's called the genetic fallacy, in which you believe that, because you know what something is made of, the something doesn't exist. My desk is made up of atoms and molecules, but that doesn't mean that desks don't exist. Similarly, my brain is made of neurons, but that doesn't mean that I'm not conscious or that consciousness doesn't exist.

I read a lot about consciousness in connection with my dissertation. In answer to your question specifically, I think that jaded's is the best answer so far. All of the "positions" on consciousness (e.g., it doesn't exist, it's an epiphenomenon, and so on) are unproven and, I think, unproveable; but what I see is that many people in philosophy, neuroscience and elsewhere are starting to agree, even if implicitly, that consciousness is useful in the process of decision-making. It's part of the same battery of human attributes (abstract language, big working / short-term memory, and so on) that seem to make people good at planning ahead and "thinking things through." This is especially true of what Antonio Damasio calls "extended consciousness"--that is, the longer-term personal awareness of the specific nature of things in one's environment--as opposed to "core consciousness," the more in-the-moment sense of self in action. People who've suffered brain damage, for examlple, in which their extended consciousness is impaired have trouble executing actions that take longer than their "window" of core consciousness (about 45 seconds), unless the rules are already laid out for them. So someone with no extended consciousness could defeat you in a game of chess, but not function normally in other ways--not recognize that a photo of a young boy is in fact a photo of their child, for example.

In Temple Grandin's new book Animals in Translation--which is astounding--there's a fair amount of time spent on animal consciousness. She argues that some animals do have consciousness to some degree--that is, that they have emotions (instead of merely feelings) which are centered around a sense of self; that they can, in various ways, "think." Does a squirrel have a self? It's hard to say, and even if it does, it's probably pretty under-extended. But other smart primates probably do, and some dogs and birds might as well, along with other animals like dolphins. In these cases we're looking at animals that make decisions of some kind. She argues that it's in the orientation response that consciousness originates. That's the response where an animal, when it hears a sound, like an airplane overhead, stops and looks towards it, and then must make a decision about what to do: run, attack, investigate, hide, and so on. Perhaps that's where animals become "conscious": they observe a thing and think about it.

Antonio Damasio, by contrast, argues that consciousness emerged from the body's automatic monitoring of its own states--its homeostatic tendency to keep itself at the same temperature, for example. There is constant "monitoring" going on in any animal at an unconscious level. His take is that consciousness is an extended kind of biological monitoring that, at root, is all about homeostasis: preserving the body from cold, heat, hunger, and thirst. The process of consciousness hooks up the older, lower-level, limbic or neomammalian functions of homeostasis with newer, higher-level neocortical abilities to problem-solve and think, to the organism's great advantage.

There are other theories: Julian Jaynes, for example, argues that consciousness emerged from the bicameral nature of the brain. And then there's the general notion that it is simply the byproduct of complexity in the brain: it has no purpose as such (the epiphenomonalist position). From this perspective, we could continue to act completely like ourselves and not have consciousness (this is often called "the zombie problem"). But this just doesn't seem supported by anecdotal evidence: people really do act differently if their consciousness is impaired.

Here's my take on it. We know that emotions are really important in what we sometimes think of as "intellectual" or "rational" processes. So, for example, even solving a math problem, at least for a person, involves intuition and feelings of some kind: aversion frmo wrong ideas, attraction to interestig ones, eagerness to solve the problem--what Jaak Panksepp, an animal scientist, has called the "SEEKING" circuit. Emotions are different from feelings: the feeling of pain, for example, can be separated from the emotion of suffering by severing connections in the brain, so that patients with chronic pain, for example, can simply stop caring about it. They feel it, but they don't have the emotion of suffering and don't feel bad.

From what I've read, my guess is that consciousness has the effect of intensifying, mobilizing, and making the system of feelings more malleable and centered on the self. It allows for more complex and nuanced responses to feelings that work in a manner extended through time. I follow Damasio, I suppose, in the idea that consciousness hooks up feeling and thinking, or allows feeling to turn into thinking.

That's just a guess, though. The truth is, nobody knows!
posted by josh at 9:11 AM on January 25, 2006 [2 favorites]

"Self-awareness" and "consciousness" are often used to mean the same thing, but I've always seen a distinction between the two.

To me, my "consciousness" is what makes me more than a biological machine. It is--for want of a less loaded term--my "soul."

My "self-awareness" is my ability to observe and analyze my own actions.

These two things certainly go hand-in-hand in our experiences, but there's no reason they couldn't be separate. As delmoi points out, a computer can analyze its own behavior, which might be described as self-awareness without consciousness. And it's conceivable to imagine a zen state in which you lose all awareness of yourself, but continue to be conscious.

I make this distinction because the answer to your question is different depending on which of these concepts you are asking about. The Darwinian utility of monitoring and analyzing your own actions seems obvious, so I assume your asking about the other kind of consciousness.

If so, one way to think about the question is: suppose it was somehow possible to extinguish somebody's consciousness without making any other change in their brains. If a friend of yours had this done to him, would you be able to tell the difference?

If you think (as I do) that the answer is "no," then that implies there is neither advantage nor disadvantage to consciousness, and it is probably just an emergent behavior of some other, more useful property (such as intellectual complexity.)

If you think the answer is "yes..." then I'd be interested in knowing how you feel you would observe the difference.
posted by yankeefog at 9:24 AM on January 25, 2006

As an aside: that Wikipedia book is pretty good. Other good sources I've found are the very good anthology by Ned Block and Gavin Güzeldere, Consciousness: Philosophical Debates, which is quite academic and centered around neuroscience and philosophy; and John Searle's tiny book Mind: An Introduction.
posted by josh at 9:24 AM on January 25, 2006

I highly recommend reading Colin McGinn's The Mysterious Flame, or at least looking at some of the pages listed under the index entry for "evolution." (Try going to that link, going to "Search Inside," and searching for "evolution" or "Darwin" or "Paley.") I don't have the book with me, so I'm not going to try to summarize or excerpt his reasoning here. But as I remember it, he concludes that what is truly mysterious is how the slightest modicum of consciousness ever came into existence in the first place. (He suggests that this could prove the existence of God through an "Argument from Sentience," though he himself doesn't believe in God.) In contrast, he believes that once consciousness began to exist, it's relatively easy to see, using Darwinian principles, why that basic level of consciousness would have evolved into sophisticated minds.
posted by Jaltcoh at 9:29 AM on January 25, 2006

My guess is consciousness is a byproduct of our abstract reasoning ability. In other words, consciousness in itself does not give an evolutionary advantage, it just came along for the ride with our enhanced ability to think in abstract terms.
posted by knave at 9:30 AM on January 25, 2006

You may be interested in Mirror Neurons And The Brain In The Vat by V.S. Ramachandran in the last issue of Edge. It's fascinating, even if I am not able to grab all the consequences.

The emergence of a sophisticated mirror neuron system set the stage for the emergence, in early hominids, of a number of uniquely human abilities such as proto-language (facilitated by mapping phonemes on to lip and tongue movements), empathy, "theory of other minds", and the ability to "adopt another's point of view".

There seem to be no doubt that mirror neurons have a lot to do with our sense of self, including consciousness.
posted by bru at 9:46 AM on January 25, 2006

I just dropped in the recommend Jaynes's Origin of Consciousness in the Breakdown of the Bicameral Mind, but I see it's already been mentioned. Jaynes certainly gets way out there (smoking bay leaves to try to recreate the oracular trance at Delphi, among other crazy pseudo-science), but his thesis is very compelling in some ways. His theory on the origin and development of religion is particularly fascinating and I find that I'm constantly reminded of it.
posted by stopgap at 10:17 AM on January 25, 2006

I have two things to add:

1) The only relevant question that can be reasonably answered by evolutionary theory is why some species died out. Anything that lives long enough to procreate and has access to enough resources and facilities to avoid predators so that its children can live to do the same will survive. Everything else dies out. Just because some quality or trait has survived doesn't mean that it's good. Evolution doesn't lead towards the best solution, it weeds out the ones that are sufficiently bad.

2) I recommend Jeff Hawkins's recent book On Intelligence, in which he makes the case that consciousness == prediction. Prediction is generally good for survival.
posted by Caviar at 10:20 AM on January 25, 2006

There have been discussions on the Blue about this many, many times. If you have time to kill, read them.
posted by Gyan at 10:41 AM on January 25, 2006

I'm going to tackle a limited type of "consciousness," and I'm going to tackle it with pure speculation. That said...

Imagine a chess piece that isn't self-aware, but is aware of its environment. It can tell when an enemy is nearby, and can (instinctually) dodge to the left or right to avoid collision.

Now imagine another chess piece that IS self aware. It's brain contains a mental-map of the chess board with a YOU-ARE-HERE dot. So this piece always knows where it is in relation to all the other pieces on the board. Wouldn't this be a survival advantage?

YOU are a chess piece in your world. If you aren't self-aware, you're missing a major piece of data.

As a side note, Harold Bloom believes that just a few hundred years ago, people weren't conscious the way they are today (see "Shakespeare and the Invention of the Human") I like this claim, because it's so bold. But I have trouble buying it. Does anyone know if it's taken seriously outside the Humanities?
posted by grumblebee at 11:00 AM on January 25, 2006

I don't even think it's taken seriously in the humanities, grumblebee. ... At least, I've never met anyone who takes it seriously.

It is awesome in its zaninness however. I remember watching an episode of Charlie Rose where Harold Bloom says something like: "These feelings, Charlie ... these thoughts, that we think, in our minds ... they are not ours ... they were invented ... by SHAKESPEARE!!"
posted by josh at 11:08 AM on January 25, 2006

You may be interested in Science, Consciousness, and the Soul, which includes a few scientists discussing evolution and consciousness.
posted by scottreynen at 11:18 AM on January 25, 2006

Vonnegut's quote seems predicated on the belief that some kind of giant apocalypse is just around the corner - since today humans are surviving fairly well, as a species.

The human brain allows us comfortable survival in a very wide range of climates, possibly eventually including the inky void of space!

I'm not saying humans always behave in ways rationally beneficial to the species, but certainly empirically I would say that having a big analytic self aware brain seems to work out okay.
posted by aubilenon at 11:57 AM on January 25, 2006

I would have to agree with odinsdream, the existence of consciousness isn't a given. Even a good working definition is pretty tricky. From both a Skinner and Buddhist perspective, consciousness is very much an illusion.

If we define any persons consciousness as the total of their understanding of their interaction with the inside and outside worlds, we can also define it as the limits of their understanding. If the glass is half full it's an empowerment, if it's half empty it's a weakness.

To say that a given thing has or doesn't have consciousness is surely conceit on the part of the describer. If a rock had consciousness, how would it express it in a way that you could observe? Maybe you lack the degree of consciousness it takes observe consciousness in a rock (or a dog, or the raving homeless nut job who's sitting at the other end of your subway car). Or maybe every atom is a mote of consciousness just waiting to express it's potential.
posted by doctor_negative at 12:04 PM on January 25, 2006

I have to disagree with you here doctor_negative. By "consciousness" the poster means something that very clearly does exist: the physiological phenomenon of awareness, the capability to experience qualia. We know it exists because we can notice when it's gone. People who suffer brain damage, for example, can end up having less consciousness than normal people. Victims of neurological damage can also palpably experience and describe failures of their conscious sytems. Blindsight is a good example of this. In fact, working with failures of consciousness is one of the main ways in which researchers are trying to get a handle on what it is and where it's located in the brain.

From both a Skinner and Buddhist perspective, consciousness is very much an illusion.

Perspectives aren't science; Skinner's 'black-box' view of the mind is decades old and mostly outmoded. The Buddhist sense of consciousness is quite a lot wider than the sense we're talking about here. Consciousness, in this sense, is a capability of the brain, and it exists at a material level. Consciousness in the Buddhist sense is what you descrie: a total range of possible and known felt experience.

I struggle with this problem all the time, since my research area as a graduate student is consciousness and the novel. There are all sorts of "consciousnesses": political consciousness, class consciousness, self consciousness, consciousness in the religious or spiritual sense, and many more. In fact, if you look in the OED, the origins of the word "consciousness" are con + scio: used, as it was back then, in the sense of knowing things together, it was a lot closer to the idea of social, political, cultural, or collective consciousness than it was to the idea of consciousness we know today: that is, phenomenal, qualitative consciousness.

Of course, the materiality of consciousness doesn't detract at all from its awesomeness. It's totally unbelievable what consciousness allows. Really, if you don't believe in a higher power, the entire universe of value and meaning results from it.
posted by josh at 12:52 PM on January 25, 2006

Well, you're not really disagreeing, because I merely said it's existence was questionable. My point was really, in retrospect, to say that what we call consciousness may be illusory in that it's really part of a larger phenomenon. As for whether Buddhists understanding of consciousness is scientific or not, I'd say it's irrelevant. Whoevers right wins the prize there, and I'll put my money on the Buddhists. Also, in regard to your last sentence, I would argue that consciousness IS the higher power from which the universe (and all the value and meaning contained therein) arises.
posted by doctor_negative at 3:13 PM on January 25, 2006

Daniel Dennett, a philosopher at Tufts has some stuff to say about this -- I find it all pretty incomprehensible (and without any 'bottom') but it may be just the thing you are looking for.
posted by bluesky43 at 5:10 PM on January 25, 2006

As for whether Buddhists understanding of consciousness is scientific or not, I'd say it's irrelevant.

which brings up some interesting questions ... how does one objectively view one's own consciousness? ... when scientists are observing consciousness in people are their observations of consciousness itself, or simply descriptions of consciousness by the conscious people or what the conscious people are able to do?

i offer no answers, but i think this whole area is very tricky ... and i wouldn't disregard the records of those, like buddhists, who have been actively and intently studying their consciousness ... perhaps it's not direct scientific observation ... but is direct scientific observation even possible?
posted by pyramid termite at 10:12 PM on January 25, 2006

I like this claim, because it's so bold. But I have trouble buying it. Does anyone know if it's taken seriously outside the Humanities?

I think it's credible to argue that the way we think about ourselves, as biological entities and conscious beings, is informed by a discourse between science and literature. My doctoral work was on the emergence of a way to talk about the self by reference to the nervous system, which was only properly discerned in the late 1600s. The first neurologists took their language from literary sources, and their own terminology was reabsorbed into literature.

You certainly couldn't think of yourself as 'sensitive' in the same way before that body of literary and scientific work appeared. That's not as bold as Bloom's theory, by any stretch, but it does imply a linguistic and epistemological mediation of self-consciousness. That's to say, the way we understand our consciousness has the capacity to affect it.
posted by holgate at 3:28 PM on January 26, 2006

I just stumbled on this Nova Spivack's idea: is consciousness something fundamental to the basic structure of the universe, like space, time and energy? He compares it with electricity that we can channel with the right apparatus. Our mind would then be the "right apparatus" to "channel" and use consciousness.
Very original.
posted by bru at 7:00 AM on January 27, 2006

bru, panpsychism is hardly original.
posted by Gyan at 10:18 AM on January 27, 2006

Gyan, thanks, I didn't know this word.
Although, when I googled it, I recognized the concept: I don't know why, but I had always thought of this idea as a spiritual (religious) one whereas, when reading Spivack's, I understood it in a material, darwinian way.

I have a tendency to dismiss most religious beliefs as irrelevant; but this dual perspective on the same concept makes me understand better why so many people (in this thread and elsewhere) are interested in oriental philosophies.
posted by bru at 1:52 PM on January 27, 2006

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