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Saturday, May 12, 2007 | Reason : Evolution and Biology | print version Print | Comments

Document Consciousness Comes from DNA

by Carl Sagan and Ann Druyan (edited by John Hartman)

Thanks to John Hartman for this edited article.

Consciousness Comes from DNA

Happy the elephant recognises herself in a mirror. Image: Diana Reiss

Excerpts from Shadows of Forgotten Ancestors / A Search For Who We Are by Carl Sagan and Ann Druyan

Selected, edited, and updated with new evidence by John Hartman / May 8, 2007

Is the origin of consciousness an unfathomable mystery? Does it require the insertion of an immaterial soul into each human being, but no other animal, at the moment of conception?

Consciousness and self-awareness are, in the West, widely esteemed as the essence of being human (although the absence of self-awareness is considered a state of grace and perfection in the East); the origin of consciousness is imagined to be a unfathomable mystery, or – not so different – the consequence of the insertion of an immaterial soul into each human being, but into no other animal, at the moment of conception. Consciousness may not be so mysterious a trait, though, that supernatural intervention is needed to explain it. If its essence is a lucid awareness of the distinction between the inside of the organism and the outside, between you and everyone else, then, as we've argued, most microorganisms are to this degree conscious and aware; and then the origin of consciousness on our planet dates back more than 3 billion years. There were vast numbers of microscopic creatures then, buffeted by sea swells and ocean currents, reveling in the sunlight, each with a rudimentary consciousness – perhaps only a micro consciousness, or even a nano – or picoconsciousness.

If the information in the DNA has come to be through the patient evolutionary process, why is a god needed to explain the injection of data, genes, or souls in the first place?

So could souls have provided consciousness back then? A deity responsible on a case – by – case basis for precision injection of souls into this immense host of tiny creatures over the full range of geological time would be a very fussy as well as a very inefficient creator. Why not design it right from the beginning, and let life run by itself? Would the god responsible for the subtle, elegant, and universally applicable laws of physics do such slapdash, error ridden, journeyman work in biology – requiring hands-on attention to every pathetic little microbe when they already know perfectly well how to reproduce themselves and vast stores of information? Instead, all the god has to do is to encode directly into the DNA of a few ancestors whatever information souls are required to know. Souls and consciousness could then pass, on their own, from generation to generation, freeing the god for other matters, perhaps some of greater urgency. But if the information in the DNA has come to be through the patient evolutionary process, why is a god needed to explain the injection of data, genes, or souls in the first place?

Is the ability of a cell to distinguish itself from another cell evidence of consciousness and self-awareness?

Every cell in a healthy human body can make the distinction between itself and others, and those that cannot, that suffer from auto-immune diseases, quickly kill themselves off or fall prey to disease microorganisms. But maybe you're thinking that a cell distinguishing itself from another cell (in your body or in the primeval sea) is not what is generally meant by consciousness or self-awareness, that even for the exceptionally unreflective humans there's more to it than that. Yes. As we've said, only the most rudimentary kind of consciousness can be imagined in the early history of life on Earth. Of course, there's been substantial evolution since then. Do we know – it might be a very hard thing to know – whether any other animals have our kind of self-awareness?

Is there compelling evidence chimps, orangutans, and dolphins are conscious and self-aware?

In 1977 the psychologist Gordon Gallup published an article entitled "Self-Recognition in Primates." When chimpanzees born in the wild were confronted with a full-length mirror, at first – like other animals – they thought the reflection was someone else. But within a few days they had figured it out. Then they'd use the mirror to preen, and to examine inaccessible parts of themselves, looking over their shoulders to view their backs, for example. Gallup then anesthetized the chimps and painted them red – in places that they could see only in the mirror. Upon regaining consciousness and resuming the pleasures of self-examination in the mirrors, they quickly discovered the red marks. Did they reach out to the ape in the glass? Instead, they groped their own bodies, touched the painted areas repeatedly, and then smelled their fingers. They trebled the time they spent each day examining their mirror images.

Among the other great apes, Gallup found mirror self-awareness in oranges, but not gorillas. Later, he found it in dolphins. We are conscious, he proposes, when we know we exist, and have a mind when we monitor our own mental states. By these criteria, Gallup concludes, chimps, orangutans, and dolphins are conscious and have minds.1

What would it mean if elephants could pass a mirror self-awareness test?

Elephants have recently demonstrated they too are conscious and have minds. "We report a successful mirror self-awareness elephant test and report striking parallels in the progress of responses to mirrors among humans, chimps, orangutans, dolphins and elephants," said Diane Reiss and her researchers. Their findings were reported in the October 2006 in the Proceedings of the National Academy of Sciences.

In the study, three Asian elephants were introduced to a huge, 'elephant-resistant' mirror at the Bronx Zoo in New York City. The female elephants, Happy, Patty and Maxine, were observed while they interacted with the mirror.

Humans, chimps, orangutans, and dolphins typically go through four stages after being introduced to a mirror. In most cases, an animal will first engage socially with the reflection through visual, vocal or agonistic displays. Interestingly, the elephants in this study showed no social interaction behaviors.

The second stage of mirror self-recognition is physical inspection of the mirror. Maxine and Patty both threw their trunks over the mirror, reared up on their hind legs in order to peer over the top, and knelt down in front of the mirror, attempting to get their trunks underneath it.

The third stage is repetitive testing of the mirror. Each elephant tried out some vertical and horizontal head and body movements in front of the mirror, moving in and out of view of the mirror. The elephants also used the mirror as a tool to investigate their own bodies. They brought food over to the mirror and watched themselves eat. They also inspected the insides of their mouths and pulled on their ears with their trunks.

The fourth and final stage is a test. For the scientists to be sure that the elephants were recognizing themselves in the mirror, they had to pass the standard 'mark test'. The elephants each had two marks painted on their heads. A visible X was painted on the right-hand side and an invisible mark was painted on the left-hand side. The elephants were only able to see the visible mark if they looked in the mirror. The scientists observed the elephants to see if they would touch the visible mark.

Happy repeatedly touched the visible X after seeing it in the mirror. The other two elephants did not touch the visible mark on their foreheads, and none of the elephants touched the invisible mark.

"Only one elephant, Happy, passed the mark test," explained Reiss. But only one elephant needed to pass the 'mark test' to demonstrate that elephants are capable of self-recognition and self-awareness. "This is consistent with reports of tests with the great apes. Not all of the apes that are tested pass the mark test, nor do all children it turns out," she said.

According to the Reiss, this study shows that the ability to distinguish one's self from others has evolved independently in several branches of animals. "This is a marvelous example of cognitive convergence," she said.2

Does the DNA of humans, chimps, orangutans, dolphins, and elephants provide the instructions for these species to become conscious and self-aware?

Yes. The mirror self recognition tests provide us with the compelling evidence we need to believe this is true for all of these species. It is clear the ability to distinguish one's self from others has evolved independently in primates, dolphins, elephants and their DNA encoded cells.

Source References

1. Sagan, Carl. Shadows of Forgotten Ancestors / Carl Sagan and Ann Druyan. Chapter 19. What is Human? Pages 377-379. (2002) http://www.amazon.com/Shadows-Forgotten-Ancestors-Carl-Sagan/dp/0345384725

2. Hayes, Jacqui. Elephants Possess Self-Awareness. Cosmos Online. (2006)http://www.cosmosmagazine.com/node/812

Comments 1 - 18 of 18 |

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1. Comment #39897 by Rtambree on May 12, 2007 at 8:15 am

The problem with words is that they force our brains to think discretely... e.g. either the animal is consciousness or it is not.

Thinking along a continuum, i.e. that there's a spectrum of consciousness, is more difficult.

There's no one event in the lifetime of a embryo - fetus - baby - infant - juvenile - adult, where it suddently becomes conscious.

The brain is still developing into late teens - early 20s, and then it peaks and starts to die in the late 20s, so consciousness is always in flux.

Question - if language is the foundation to human consciousness through the ability to manipulate abstract concepts, are people with large vocabularies more "conscious" than people with people with small vocabularies? Can they have more thoughts?

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2. Comment #39906 by beelzebub on May 12, 2007 at 8:45 am

 avatarI love this line
"Gallup found mirror self-awareness in oranges, but not gorillas."
Conscious fruit? Amazing!! :-)

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3. Comment #39914 by The Buxter on May 12, 2007 at 9:17 am

A very interesting thing about the development of consciousness, and animals showing sign of human-like consciousness, fx. elephants passing mirror-awareness tests and gorillas learning sign-language, is wether the consciousness is linked to the possibility of these feats, or the feats themselves. In other words: Are humans/animals able to communicate and recognize ourselves in mirrors (and shadows, reflections and so forth) because we are conscious, or are we conscious because we communicate and recognize ourselves?

It would be very interesting to follow the development of animals being raised in mirror and language-filled environments!

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4. Comment #39929 by ghostbuster on May 12, 2007 at 10:23 am

I have always believed that consciousness was not something that has likely just evolved on earth either. Intelligent life with consciousness has been seen as a possible "fluke" on earth, that it is entirely a rare event "out there". Why should it be any more rare an evolutionary advantage than any other trait--like ears, eyes, voice boxes etc. I am with Simon Conway Morris on this topic; biology works with the other sciences. If intelligence is rare, it will only be because it might very well have a built-in mechanism for "self destruct" when it becomes not an advantage to the species that exhibits it or to the other species that must endure the results--case in point, our earth.
By the way, a sideline, I know some people who cannot tell the difference between what they see in the mirror and what they are in reality. The power of the mind!

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5. Comment #39931 by Nebularry on May 12, 2007 at 10:26 am

I find this study to be absolutely fascinating! It will be interesting to follow further developments along these lines. Apparently, we humans are not as "divine" as some theologians would have us believe. Or do some animals have souls in the same sense that humans do? Hmmm . . ?

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6. Comment #39932 by ghostbuster on May 12, 2007 at 10:26 am

By the way, consciousness was once linked to language; no more. The ability, for example, for an artist to visualize something comes before his or her inner dialogue (language). I suspect animals have varying degrees of this, along with scents.

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7. Comment #39936 by Thanny on May 12, 2007 at 10:43 am

I find myself irritated by this mirror test. Or, rather, by the lofty interpretations of it.

My cat recognizes its own reflection in the mirror, but doesn't care. It doesn't inspect itself, or meet any of those other criteria.

So how do I know that it knows the reflection is of itself? Because my cat is fiercely territorial, and would attack another cat on the spot.

If you actually think about it, *any* animal which, in nature, has occasion to visit a watering hole of some sort, will likely be equipped to recognize its own reflection. Most simply ignore it.

These mirror tests confirm only that the animals in question (including humans) are vain enough to be interested in looking at themselves.

Any animal that has no reaction whatsoever to its image in a mirror probably knows it's a reflection, and simply doesn't care.

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8. Comment #39938 by pewkatchoo on May 12, 2007 at 10:53 am

 avatarI have renewed respect for oranges!

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9. Comment #39942 by Wilfred C. Lyon on May 12, 2007 at 11:11 am

I was around at the University of Michigan when the "Worm Runner's Digest" was around. It was there discovered that learning could be transferred via DNA from planaria to planaria. These are quite low level animals. Learning IS DNA dependent.

Also, having grown up in a rural environment with many sorts of barnyard animals, I never questioned the consciousness of these animals, they WERE conscious. I don't have controlled test data like the mirror test, but a lowly bovine (canine, swine,etc) that can respond to their name and ignore the other names is somehow conscious of themselves.

In particular, we had one younger heifer who was not depolled (dehorned) and she became the leader of the herd, not through using her horns as fighting tools, but as tools to be manipulated with cleverness for the use of the herd. We had the usual pin-in-the-hole door handle/locks. We had a bolt screwed into the pin as a handle to help move the pin out of the hole. She learned by observation and then trial that she could hook a horn on the bolt and move the pin out of the slot. Thereby gaining free access to the barn, and its contents at her will, not always ours. After learning that trick, she learned to open the door between the manger and the hay/grain area. This was a door with a simple bent nail latch, swing it out of the way and the door would open, swing it back down and the door would rest against it and the jamb and the door would stay closed. She could not reach the nail, but repeatedly tried to hook the "imaginary bolt". This bumped the door back and forth on the nail and jamb. Eventually the nail would swing out of the way bit by bit, the door would open and she and the herd would have access to the hay. The grain was storred in a steel barrel to keep vermin out and had a steel top with a lip suitable for a barrel band. We didn't have the band and didn't need it for the usual vermin. She learned to get her horn between the barrel and the top and flip the top off, gaining accress to the grain.

This does not prove awareness of self, however, she was one of the few bovines that "knew" her name. There was more intelligence there than usual, and the herd and she was aware of her position as the leader.

One of my daughters kept rabbits. These animals (the rabbits, not my daughters) are not noted for their great intelligence. But my observation of them was that they were keenly aware of each other and each other's well being, even when kept in separate pens. This specicies specific awareness, as I said, was very keen, notable when one of them died, all were upset and seemed to mourn. This does not necessarily denote self awareness, but when I was left with only the last two, a male and female long time pen mates, who were by then quite old and one died, the other went from relative youth (compared to the other) and good health, to death in less than two weeks. I felt that it was entirely from an awareness of being alone, i.e., some form of self awareness.

I conclusion, I think that when we begin to examine self-awareness, we will indeed find a continuum down the evolutionary species chain. The challenge is understanding what to test and how to test. The intelligence is there on their part, it has simply been lacking on our part due in large measure to our own belief.

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10. Comment #39945 by Vadjong on May 12, 2007 at 11:19 am

 avatarA great starting point into the science & philosophy of consciousness is still :
The Mind's I, Fantasies and Reflections on Self and Soul ; (composed and arranged by) Douglas Hofstadter and Daniel Dennett, 1981

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11. Comment #39957 by matlot on May 12, 2007 at 11:40 am

[7. Comment #39936 by Thanny on May 12, 2007 at 10:43 am

I find myself irritated by this mirror test. Or, rather, by the lofty interpretations of it.

My cat recognizes its own reflection in the mirror, but doesn't care. It doesn't inspect itself, or meet any of those other criteria.

So how do I know that it knows the reflection is of itself? Because my cat is fiercely territorial, and would attack another cat on the spot.

If you actually think about it, *any* animal which, in nature, has occasion to visit a watering hole of some sort, will likely be equipped to recognize its own reflection. Most simply ignore it.

These mirror tests confirm only that the animals in question (including humans) are vain enough to be interested in looking at themselves.

Any animal that has no reaction whatsoever to its image in a mirror probably knows it's a reflection, and simply doesn't care. ]

Thanny makes a good point methinks

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12. Comment #39996 by bitbutter on May 12, 2007 at 3:12 pm

 avatar@thanny

These mirror tests confirm only that the animals in question (including humans) are vain enough to be interested in looking at themselves.


The fact that the animals even know that they are looking at themselves is the crucial thing though.

My cat also ignores her reflection in the mirror now after a period of being afraid of it. the fact that she now ignores it doesn't mean that she understands that it's herself that she's seeing. other explanations might include that she now knows that the cat in the mirror never attacks, never washes her, doesn't smell of anything and is otherwise an uninteresting playmate. Perhaps she even understands that it's not real (like the images on the television or shadows).

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13. Comment #40016 by Duff on May 12, 2007 at 5:08 pm

If anyone thinks consciousness is simple and can be reduced to a few observations should read Susan Blackmore's Conversations on Consciousness, an overview of the people who really have thought about this subject. None of these things are as simple as we would like to believe. Don't commit the cardinal sin of oversimplification.

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14. Comment #40066 by CDG on May 13, 2007 at 1:02 am

I agree with bitbutter and Duff. To suggest Vanity at these levels just doesn't seem to fit. One thing to consider is that there are many different levels of consciousness. Some primitive levels and some advanced. What is actually being gleened by the mirror test is probably too complex and/or subjective/ancectdotal to have an oversimplified explanation.

I like the article though. And I love Carl Sagan.

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15. Comment #40071 by Logicel on May 13, 2007 at 1:51 am

 avatarWilliam C. Lyon, nice post!

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16. Comment #40157 by Martha on May 13, 2007 at 12:05 pm

 avatar"Every cell in a healthy human body can make the distinction between itself and others, and those that cannot, that suffer from auto-immune diseases, quickly kill themselves off or fall prey to disease microorganisms."

When I read sentence, I immediately thought (reflected) on the psychological damage that religious dogma does to the immature mind of the human child.

It is no accident that those who have been thoroughly indoctrinated with religious dogma (from one generation to the next) as children are the least likely to have developed the ability to reflect - not least on the on the consequences of their own actions as adults. This unhealthy inability is due to their childhood religious conditioning, which automatically decimates the natural development of a separate Self, i.e., from those who have responsibility for their very lives, as infants and young children. This is the time when our brains are at their most crucial stage of development.

The end result of such desensitizing childhood conditioning is the adult sociopath, i.e., an infant in an adult's body.

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17. Comment #40239 by Dianelos Georgoudis on May 14, 2007 at 1:25 am

The article claims that "elephants have recently demonstrated they too are conscious and have minds". And how was that demonstrated? "We report a successful mirror self-awareness elephant test".

Really? So mirror self-awareness (i.e. the ability of a physical system to distinguish itself in a mirror) implies that it is conscious and has a mind? Why, if that is so then I can build an artificial consciousness with about 100 Euros and a few days of work.

(BTW, thanks for the recommendation, Duff. This looks like a good book.)

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18. Comment #40542 by hoops mccann on May 14, 2007 at 12:52 pm

 avatar"Gallup found mirror self-awareness in oranges..."

I *thought* I heard a scream when I was operating the juicer this morning!

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