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Kevin Dumas
12/4/06
The Relationship between Evolution and Consciousness
A quick note to the reader: Evolution, while accepted by a majority of people, remains a theory. This paper is written with the
assumption that evolution is real and that consciousness is a byproduct of evolution.
Consciousness is our most intimate possession. Every moment we are aware, we
are subject to our consciousness. While we know little about “conscious-law,” we know
much about the “conscious experience;” it is, effectively, our entire existence. To a
Genetics major such as myself, one’s creation and structure is controlled and determined
by one’s genes. With that said, it is only natural to ask questions about where
consciousness and evolution meet, how they interact with one another, etc. This paper
will investigate the relationship between these two pillars of existence – our blueprint and
our way of knowing that blueprint – and their coupled effects on the human being, which,
for the remainder of this document, will be viewed as a completely conscious animal
produced and governed by the laws of evolution and natural selection. Before I venture
into a discussion on the relationship between our consciousness and evolution, I will first
define the two.
Evolution is the theory that change in a population over time is due to shifts in
allele and gene frequencies. The theory is extended to say that the animals that have the
most beneficial or “fit” genes are most likely to pass these genes onto the next generation.
Thus showing that natural selection (survival of the fittest) is due to genes inherited over
time. Consciousness, while more familiar then evolution, is more nebulous and much
harder to define. Consciousness can be loosely defined as subjective experience of the
mind and/or the ability to comprehend one’s relation to one’s environment.
“Natural selection is the only physical process we know of that can simulate
engineering, because it is the only process in which how well something works can play a
causal role in how it came to be” (The Blank Slate, 52). This statement from Steven
Pinker gives a wonderful analogy to how we evolved into the beings that we are today. It
is widely accepted that our organs, muscles, bone structure, endocrine system, etc. all
evolved by means of natural selection with the purpose of allowing us to propagate our
genes and thrive in our environmental niche. Once one has realized this fact, it is only
matter of 1) recognizing one’s instincts, 2) acknowledging that the brain is an organ, and
3) realizing that our behavior and mind are products of the brain and thus products of
evolution as well. Now that we got the “what” and “how” out of the way, we can move
onto the “why.”
Why consciousness evolved:
For us to truly answer why consciousness evolved, we would have to define a
point where consciousness “officially emerged.” This would require finding two
organisms on the evolutionary tree, dubbing one “conscious” and the next “unconscious.”
This is impossible for a variety of reasons – which I will not delve into. It also requires a
more complex definition of consciousness. In this case, I feel the most appropriate
definition is that of Antonio Damasio who claims that consciousness can be divided into
two groups: core consciousness – the consciousness that arises from an organism’s
interaction with its environment (including itself and its memories) and extended
consciousness – the consciousness that arises from an organism’s auto-biographical selfperception (Wikipedia, extended consciousness).
Through experiment and observation of animals in their natural habitat, we have
discovered many animals have extended consciousness and many more have core
consciousness. Animals such as elephants and dolphins have proven they can recognize
themselves in mirrors (thus proving self awareness and extended consciousness) and
anyone who has owned a cat or dog will argue that their pet is capable of emotional
bonding and interaction with their environment (thus proving core consciousness). We
can therefore postulate that both core and extended consciousness emerged in a common
ancestor and was present before humans made their transition from “animal” to “human.”
While there is much to be learned from this branch of study, this paper is specific
to human consciousness. That being said, we will only look into why the human
consciousness is so complex (or so we think/hope) when compared to that of the cat,
cow, etc.
One common theory is that our complex extended consciousness was a spandrel
(unintended by-product) that emerged when technology allowed our minds do worry
about goals other then just surviving. “Tools relieved us of many daily chores. Our
emotions had been invented to help cope with those chores, but tools made emotions
obsolete… Those emotions flowing through our mind eventually got organized, and
yielded thought. Thought eventually yielded a continuous flow of emotions and a concept
of the self: consciousness was born” (A Simple Theory of Consciousness). We see here
how simple the change from “primates with primitive emotions and a primitive
conscious” to present day “human beings” was with the development of tools – tools that
freed the mind to do as it wished – which, during the Pleistocene era, was figure out ways
to obtain food more efficiently – and thus develop our enduring sense of curiosity and
complex problem solving abilities.
Another theory is that as primates, competing for mates and limited resources in a
world where hominids were hardly the dominant race, developed several schemes to
throw off and trick competing members of the same sex. Human ancestors developed an
increasingly complex consciousness and sense of self in order to minimize being
exploited and maximize exploitation (The Evolution of Consciousness). Supporting
evidence of this theory can be seen in chimpanzee communities. A chimpanzee will lead
his companions away from a newly discovered food source so that he can consume it in
privacy and comfort rather then a chaotic rush (How the Mind Works, 193). In such a
case, the primate with the more developed sense of motives (and thus self) would have an
undeniable advantage.
Yet another theory is that consciousness is a by-product from our evolved
problem solving abilities. According to How the Mind Works by Steven Pinker, humans
are likely to have evolved such a developed sense of self and such a complex
consciousness because of four specific traits. The first is our vision. As visual animals,
with perception of both depth and color, humans have the ability to distinguish what is in
the world (via color and shapes) and where things are in the world (via a highly
developed sense of spatial location and an intuitive sense of physics). The second is
group living. Living as a group has many benefits today and had even more during our
early evolution. Such benefits include increased awareness of one’s surroundings, (more
eyes, ears, etc.) teamwork (more hands to pick more fruit) and increased traffic of
knowledge (more experience to be shared and learned from). Next is the hand. Our hand
allowed us to use tools. Using tools allowed for more efficient food gathering techniques
which meant more calories and thus more energy that could be devoted to an increasingly
large (and metabolically expensive) brain. Lastly, there is hunting. Hunting gave
humans “sporadic packages of concentrated nutrients” in the form of protein – a vital
necessity for our ravenous brain. As we became more efficient at hunting, our brains
grew bigger. This allowed for the development of more sophisticated technology, which
allowed for more food, and thus a bigger brain, and so on and so forth (How the Mind
Works, 191-195). With the evolution of so much brain power devoted to such a limited
set of problems, consciousness was bound to emerge eventually.
Physiological changes that benefit consciousness:
According to neurobiology, our consciousness is directly tied to our brain; that is,
the mind is a derivative of the brain. Where exactly the divide between the two is has yet
to be determined, yet we can see that changes in brain structure and function, both over
our lifetime and over the millennia, have led to changes in our mind.
One such example is the change in our brain’s composition during our lives.
During our second trimester in the womb and our teenage years, our brain experiences
what is called an “exuberance” or overproduction of gray matter – the thinking part of the
brain that processes information and leads to decision making and data analysis. This
overproduction of gray matter right before our entrance into the world and our entrance
into adulthood is no coincidence. Gray matter is essentially the part of the brain that
holds memory, learns and makes decisions. The overproduction of gray matter during
these two periods of our lives are timed to allow us to learn skills when we need it the
most – it is essentially our genes “making room” for storing newly learned knowledge
and potentially advantageous skill sets.
An important correlation to the overproduction of brain matter is the following
stage of pruning. Pruning is a process in which excess gray matter that has not been put
to good use (or put to use at all) is decomposed and reabsorbed by the body. While this
does limit our learning in later years (you can’t teach an old dog new tricks) it prevents
our body from having to maintain the high cost of needless brain tissue throughout our
lifetime – something that could prove devastating in times of famine.
Another example that shows evolution’s undeniable mark on our noggin is the
two processing streams we have developed. In the 1960’s, Benjamin Libet stumbled
across an anomaly of consciousness when he placed electrodes on patient’s cortex during
open brain surgery and found that conscious awareness occurred only after a half second
of neural activity. If the findings and conclusions of this experiment are accurate, then
much of what we do physically would have to be accomplished without our conscious
awareness. To explain this oddity, a “two stream” hypothesis was formed by Milner and
Goodale. This hypothesis states that the brain has two streams with which it processes
information. The first stream is the dorsal stream - a quick response, reflex controlling,
spatial awareness pathway that travels from the visual cortex to the occipital and parental
lobes. The second is the ventral stream – a slower stream that travels from the visual
cortex to the temporal lobe and the limbic system. It controls object recognition and form
representation. These two streams probably developed independently over time. The
dorsal stream (the quicker, simpler and probably older) was developed by an early
ancestor in response to quick predators and, possibly, fierce rivals. A quick response,
unconscious pathway that allowed an organism to avoid harm was, no doubt, invaluable
to primates (and earlier animals) living on the ruthless African savannah. In a similar
fashion, the ventral stream was, no doubt, a more recent adaptation designed for more
conscious actions such as abstract thought and facial recognition.
Yet another, more general, observation of evolution’s touch on our brain is it’s
size and layout – completely out of proportion when compared to the rest of the
mammalian world, yet perfectly designed to fit our niche. Our three pound brain is three
times too big for a primate our size. Due to the gargantuan brain size, the olfactory bulbs
– which make sense of what we smell – have been whittled down to one third of what
they should be (perhaps forcing us to rely on our sense of sight and promoting the
formation of the highly specialized fusiform gyrus and, possibly, the ventral stream). The
area that makes sense of sound and understands language, along with the prefrontal lobe
– the area responsible for executive decisions – is roughly twice what it would be in a
normal primate (How the Mind Works, 183-184). These changes, along with several
others, are the foundation of our intelligence and consciousness.
The effect of evolution on our psyche:
The human psyche is littered with relics from our primate past. Many of our
natural phobias, preferences, and dislikes are designed for the Pleistocene era rather then
today’s post industrial/agricultural revolution era. The most common example is that of
our fears. Human beings, like all primates, have an undeniable hatred and fear of spiders,
snakes and other venomous organisms. This fear is well based – spiders and snakes
inhabited the same trees and brush that our ancestors did. Those that ran from snakes
were more likely to survive – and thus more likely to spread genes – then those that
didn’t.
This evidence is even more effective when juxtaposed to the question. “Why
don’t we have a fear of cars, guns, or contraceptives?” Indeed, all of them have proven
much more deadly and/or sexually inhibiting to humans then spiders and snakes have
ever been, yet we do not fear them because these objects did not exist during the early
years of our existence. As Pinker put it “Had the Pleistocene savanna contained trees
bearing birth-control pills, we might have evolved to find them as terrifying as a
venomous spider” (How the mind works, 42).
We see other relics of our Pleistocene past in our behavior and choices. Any kid
(and most adults) given a choice of eating an ice cream cone or a spinach salad will
choose the ice cream. Why? Because our instinct tells us to prepare for the famine that
could be just around the corner; because the animal that eats as much as it can when it
can will have more offspring then the one that chooses to eat when convenient. “Human
appetite, it turns out, is surprisingly elastic, which makes excellent evolutionary sense: It
behooved our hunter-gatherer ancestors to feast whenever the opportunity presented
itself, allowing them to build up reserves of fat against future famine” (Omnivore’s
Dilemma, 106). Our choices of what not to eat are also the result of our evolutionary
journey. Our strongest desire to not ingest a material comes in the form of disgust.
“Disgust is an extremely useful adaptation, since it presents omnivores from ingesting
hazardous bits of animal matter: rotten meat that might carry bacterial toxins… ‘Disgust
is intuitive microbiology’” (Omnivore’s Dilemma, 292).
Limits of our consciousness due to evolution:
All organisms that evolve do so to fill what scientists call an ecological niche. An
ecological niche is “how a population responds to the abundance of its resources and
enemies… and how it affects those same factors” (Wikipedia, ecological niche). Because
human beings are governed by the laws of natural selection, we evolved to solve a
specific set of problems (i.e. how to build shelter, discover what foods are good to eat,
how to remember where stored items are, how to build a spear, etc.). Human beings
developed specialized brains for performing specialized tasks such as talking,
engineering, exploiting others, making mental maps and mental calendars, remembering
tasks, etc. These tasks have allowed humans to “crack the safes” that animals have made
to defend themselves. In cracking these “safes,” humans outwit nature and progress.
Otherwise put, “Humans have the unfair advantage of attacking in this lifetime organisms
that can beef up their defenses only in subsequent ones” (How the Mind Works, 190).
As I said earlier, these skill sets are specialized to perform specific tasks from a
specific era. Consequently, humans are not able to come up with the answer to every
problem they face. I will say it again: Human beings have limits. This does not mean
that humans cannot find ways in which to breach these limits. Simple machines allowed
man to minimize physical labor tasks, farming allowed man to localize his food supply,
numbers allowed man to quantify his word, planes allowed man to fly, computers
allowed man to look into the depths of his own genome. Evolution has equipped humans
with a variety of intuitive senses and talents. Among them are intuitive versions of:
physics, biology, engineering, sociology, spatial awareness, numbers, probability,
economics, logic, and language (The Blank Slate, 220). Notice that nowhere in that list is
there anything related to philosophy or introspection. These are subjects where man
meets a dead end. Over the millennia, man has progressed and expanded all the topics on
the list, but still patiently wonders why he’s here, what the meaning of life is, what his
role in life is, what consciousness is, etc. These are subjects that nature has not explicitly
given us tools to solve. At the end of the day, will knowing what’s at the edge of the
universe really help you kill that bison? Will knowing the answer to the hard problem
really help you run away from that lion? Will knowing what the meaning of life is really
make you more reproductively successful? With that said, it is not hard to see why
humans are not answering philosophical questions as fast as they are scientific questions.
It is here (at least for now) that consciousness has reached its evolutionary limits.
Our psyche, according to Pinker, is the ultimate tease. “The most undeniable thing there
is, our own awareness, [will] be forever beyond our conceptual grasp.” According to
Colin McGinn, “We are trying to crack open the nut of consciousness with tools derived
from perception of the physical world and the structure of language… These tools do
shape our conception of the brain, but for that very reason they make that conception
inadequate for understanding how the brain levers consciousness into existence” (The
Mysterious Flame, 60). Both McGinn and Pinker are believers of cognitive closure, that
is, the belief that humans cannot discover the true nature of consciousness, the answer to
the hard problem, etc. As far as they are concerned, human beings knowing every aspect
of consciousness is about as plausible as a cat knowing every aspect of long division.
A possible solution; an answer to our dilemma:
I, personally, have a different view. Human kind developed something neither of
these scientists acknowledged – a will to succeed. Humans hate to lose, hate to be
defeated, and, hopefully, do not give up because a couple of writers say we should.
Humans have harvested a great deal of knowledge about philosophy implicitly. With that
said, I feel human kind can and will learn a great deal more about consciousness by
taking “the road less traveled” and proving once again that our will to progress is stronger
then the physical limitations nature has given us.
Bibliography:
Carruthers, Peter. "The Evolution of Consciousness." The Evolution of Consciousness. 4
Dec. 2006 <http://cogprints.org/1205/00/Concevol.htm>.
"Ecological Niche." Wikipedia, the Free Encyclopedia. 6 Dec. 2006. 4 Dec. 2006
<http://en.wikipedia.org/wiki/Ecological_niche>.
"Extended Consciousness." Wikipedia, the Free Encyclopedia. 24 June 2006. 4 Dec.
2006 <http://en.wikipedia.org/wiki/Extended_consciousness>.
McGinn, Colin. The Mysterious Flame. New York: Basic Books, 1999. 60.
Pinker, Steven. How the Mind Works. New York: W.W. Norton & Company, Inc., 1997.
1-565.
Pinker, Steven. The Blank Slate. New York: The Penguin Group, 2002. 1-434.
Pollan, Michael. The Omnivore's Dilemma. New York: The Penguin P, 2006. 106-292.
Scaruffi, Piero. "A Simple Theory of Consciousness." 2001 Towards a Science of
Consciousness Conference. 4 Dec. 2006
<http://www.thymos.com/science/2001.html>.