After the appearance of life itself, nature’s next great mystery was the conscious creature. It is impossible to say exactly when animals first became conscious, but it almost certainly occurred in the Chapter 9 timescale, a good part of a billion years ago.
A. Defining Consciousness
A camera and an eye can both “see”. However, we would never say that a camera is “aware” of what it sees. A camera could see a hammer swinging directly at it yet never discern fear that it is about to be destroyed. How do people and animals become aware of themselves and their surroundings in a way that is different from cameras or computers?
The traditional religious answer was that we are animated by spirits, something external to our bodies. This is yet another resort to the secret trillionaire fallacy: it doesn’t explain how intangible spirits would be self-aware. Rather than wasting our time wondering how consciousness would work in an invisible spirit that may or may not exist, the modern approach is to see how much we can learn about consciousness in the physical world.
If there’s one thing that seems clear, it is that conscious thought requires a brain. Since no brain exists by itself, by extension consciousness is always associated with an animal body. The body has the essential sensors that interact with stimuli both inside and outside the body. Sensory input all travels through nerves and is processed in the brain. It is the sensory data and something about how it is processed that lead to self-awareness.
The brain creates an “inner world”, a mind. We don’t know how this is done; it is the “hard problem” of consciousness. 2 However, we do know that (disregarding higher cognitive functions for now) the inner world represents the outer world like an impression. Many patterns in the environment are transmitted directly through the body and nerves into analogous patterns in the brain and mind.
Cambrian vertebrates were endowed to sense many details about their environment. When a shark swims by, it exudes a great deal of information about itself. A nearby ray can see, hear, feel, and smell the shark. Sensory data is only the first step toward being conscious of the shark. The ray’s brain must perform a number of functions. It must distinguish between “important” signals in the environment and unimportant ones. It must pay attention to the important signals. The brain must also have memory so that it can keep track of what is changing and what is staying the same. The brain synthesizes or binds the sights, sounds, water pressures, and smells all into one mental object in space and time: “There’s a shark to the left.” The binding process seems to be a key in forming a mental state of awareness. 4
From awareness of the environment, it might not be a huge step to awareness of the self. Much knowledge about an animal’s own body derives from how it interacts with other things. Knowing that “The shark is to the left and the cave is to the right” is equivalent to knowing “I am between the shark and the cave”. The fact that an animal can sense and move its own body must also contribute to awareness of self.
There is good reason to believe that consciousness begins and ends with the material world. Remember from Chapter 10 that the properties of life derive from the way ordinary matter is organized, not from the use of extraordinary matter. Consciousness is complex and must have a complex cause. If you’re looking for complex organization, you can’t do better than a brain! Even an insect brain consists of a million interconnected neurons. 5 Neurologists routinely map mental processes to particular kinds of nervous activity in specific parts of the brain. Controlled experiments do not observe brain activity that violates physical law, for example electrical signals’ suddenly doubling as if by spiritual intervention. Despite our religious predilection to believe in spirits, it seems that the physical brain is doing all that mental processing by itself.
If consciousness leads to free will, it could very well have evolutionary advantages. A creature that is aware of pain, hunger, and the pleasure of a good meal will want to eat or flee at appropriate times. To the extent that this is hereditary and advantageous over reflexive action, evolution will pressure the development of conscious thought. There is a surprising level of opposition to this idea among philosophers, 6 but it sure seems that pleasure and pain are well honed to train survival behavior. This line of inquiry is complicated by the fact that we don’t even know, for example, if fish feel pain. If only we could ask a fish!
It is natural to speculate about the line between conscious and non-conscious animals. Consciousness is not necessarily an on / off state of being. There is a whole spectrum of responses to the environment. Even without nerves, bacteria and plants can move toward light or food. Higher on this spectrum, there are reflexes, instincts, needs, involuntary body functions, conditioning, emotions, and subconscious thoughts. Some of the more complex forms of consciousness can probably be explained in terms of the simpler forms. It is likely that animals such as octopi, snails, and lobsters have a more semi-conscious outlook on the world than we do.
To be conscious as we know it would seem to require detailed senses and a reasonably developed brain. Based on this minimal biology, good candidates for our first fully conscious ancestors were the jawless fish. (I wonder if they knew how ugly they were?!) Today’s eels and lamprey, which are very similar to the first living vertebrates, are the most primitive animals with a tectum. This is a critical command center in the brainstem responsible for coordinating sensory information, directing attention, and monitoring the body. 7 Jawless fish are also known to engage in social behavior that suggests conscious thought. 8
For most animals, social behavior amounts to communication, cooperation, and competition. Animals may cooperate to hunt, avoid predators, or keep each other clean of parasites. They may compete for food or mates. Since these are the very basics of survival, behavior became as crucial to evolution as body parts.
There are obvious ways in which cooperation and competition can help particular genes survive. Males often fight each other over females. A male that is larger, stronger, or faster is likely to defeat a less well-endowed challenger. When the winner goes on to mate, it is his genes for being large, strong, and fast that get passed down to his sons. Many species develop a sexual dimorphism for this reason, with males being substantially larger than females.
Oddly enough, even behavior itself has a genetic basis in animals. 9 Imagine a species of fish that swims in large schools. This helps most of them evade sharks or other predators. The survivors pass down genes that promote schooling behavior.
It might seem that evolution would quickly eliminate self-sacrifice, yet altruistic behavior has survived billions of years and is still prevalent throughout the animal kingdom. Altruism can provide an indirect route to survival for some alleles, since most animals live in extended families. A mother might fight to the death to save her children from a predator. The mother dies, but her genes live on. A worker bee will sacrifice having children, instead doting on the queen. But the queen is closely related to the worker, and she perpetuates the family genes. In the long run, we must remember that evolution is a tournament of genes and alleles, not organisms.
Continue to Section 9.VII: The Rest Of The World
- Fish eye image by incidencematrix, CC BY 2.0 (https://creativecommons.org/licenses/by/2.0), https://commons.wikimedia.org/wiki/File:Fish_Eye_(23776771701).jpg (accessed and saved 8/22/19). ↩
- David J. Chalmers, “Facing up to the problem of consciousness”, Journal of Consciousness Studies 2(3):200-19 (1995), http://consc.net/papers/facing.pdf (accessed and saved 8/11/19). ↩
- Pin art image: © 2013 by Ruslan Gilmanshin, Chaikovsky | Dreamstime.com – Human Face Made From Pin Board Toy Photo, royalty free license. ↩
- Rosemarie Velik, “From Simple Receptors to Complex Multimodal Percepts: A First Global Picture on the Mechanisms Involved in Perceptual Binding”, Front Psychol. 3: 259 (7/23/2012), https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3402139/ (accessed and saved 8/11/19). ↩
- Randolf Menzel and Martin Giurfa., “Cognitive architecture of a mini-brain: the honeybee”, Trd. Cog. Sci., 5(2):62-71 (2/01/2001), https://www.ncbi.nlm.nih.gov/pubmed/11166636 (accessed and saved 8/11/19). ↩
- The school of thought that consciousness provides no evolutionary advantage is called Conscious Inessentialism and dates at least to Owen Flanagan, “Chapter 7: Conscious Inessentialism and the Epiphenomenalist Suspicion”, Consciousness Reconsidered, MIT Press (1991), accessed and saved 8/17/19. ↩
- Michael Graziano, “A New Theory Explains How Consciousness Evolved”, The Atlantic (6/06/2016), https://www.theatlantic.com/science/archive/2016/06/how-consciousness-evolved/485558/ (accessed and saved 8/11/19). ↩
- See e.g. Arik Diamant and Mucky Shpigel, “Interspecific feeding associations of groupers (Teleostei: Serranidae) with octopuses and moray eels in the Gulf of Eilat (Aqaba)”, Environmental Biology of Fishes 13(2):153-159 (Jun., 1985), https://link.springer.com/article/10.1007%2FBF00002584 (accessed and saved 8/17/19). ↩
- Kenneth S. Kendler and Ralph J. Greenspan, “The Nature of Genetic Influences on Behavior: Lessons From ‘Simpler’ Organisms”, Am. J. Psychiatry 163(10):1683-1694 (Oct., 2006), https://ajp.psychiatryonline.org/doi/full/10.1176/ajp.2006.163.10.1683 (accessed and saved 8/17/19). ↩
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