Are humans the only species with a sense of consciousness? This question has intrigued me for most of my life. Having kept pets and livestock animals, and observed wild animals from both near and far, I have often wondered just how much they know about their surroundings and their place in it. Do they know how to reason out answers to questions important to them? Are they aware of the consequences of their actions? Can they anticipate what other animals, including those of close kin and other, more remote species, are likely to do in certain situations? Can they see themselves inside their minds, if they do, indeed, have minds? Do they dream?
At times it seems that other species have at least some of the attributes that we call consciousness. We may have seen our pet dogs squirm and yelp quietly while they sleep; they appear to have been dreaming. We have seen videos of dogs appearing to show guilt. We have heard anecdotes about animal behaviors that seem to indicate some kind of awareness and reasoning. There are several of these given in my book, Biology for Engineers , one dealing with coyotes that seem to use vehicular traffic accidents to eliminate dogs guarding sheep, and another showing that a mother ape seemed to understand when a caretaker signed to her that her baby was hiding a child’s discarded pacifier in its mouth. An article in Scientific American  described actions by certain birds that demonstrate complex reasoning, causal reasoning, mental flexibility, planning, social cognition, and imagination. I have seen sheep act as though they had an altruistic sense when they called to others when they were the only ones who noticed when grain was poured into their feed trough. Certainly, these animals seemed to be at least partially conscious, if not all the way.
There was an interesting article on consciousness in the November–December 2019 issue of American Scientist that piqued my interest. In it, Chittka and Wilson  posited that consciousness is an evolutionary trait that exists in all animals to at least some extent. The implications of this hypothesis are that: 1) consciousness is preprogrammed to exist as an ability shared among many species, similarly to how bodily forms and functions are homologous among various species, 2) consciousness abets survival and reproduction, and so, like other evolutionary traits, is genetically determined with different permutations that make adaptation to different environmental factors a criterion for continued existence, and 3) there may be different qualities of conscious abilities depending on the hierarchical level of the animals in question. Most of their example models were of honey bees, which they indicate, have at least some of what we might attribute to a certain level of consciousness.
They described several of the attributes of consciousness:
- Self-awareness. Knowing that they exist, and knowing their place in the world.
- Internal representation of the world. The ability to visualize things in their environment not necessarily present at the time.
- Ability to determine consequences of one’s own actions, as opposed to actions or reactions in response to external forces.
- Ability to plan and adapt plans when required.
- Ability to learn.
- Display of emotional states.
- Self-medication, such as mood-altering compounds (e.g., alcohol), with expected results.
- Ability to focus attention on specific sensory or internal inputs at the exclusion of everything else.
In the article, they made a strong case, giving evidence that animals, even as low on the hierarchy as insects, display these attributes to certain degrees (including a sense of self-awareness). What they say is amazing. It means that we are not alone in our realization of the world; other species place us in their world view just as we place them in ours. It also has ethical implications for what we as humans do to and for the animals that inhabit the planet with us.
I assume that everyone has days when they are “just not themselves,” or “out of sorts.” I know I have. These are times when one feels dull and less aware of things or people around them. They are not as sharp thinking as they are at other times. They are not as able to anticipate or understand the actions of other people as well as they can on better days. From this, I can imagine that consciousness comes in degrees, just as with many other biological features and traits; most of biology comes in a continuum rather than in discrete pieces. Hence, the consciousness that may exist in lower level animals may not be quite as astute as consciousness in humans at the top of their game.
There is also the paradox that research has shown that many actions that we take are plotted subconsciously first before we become aware of them. Conscious behavior is, in many cases, not really conscious at all until the neural inputs reach the cerebrum. At that point, the choice made is whether or not to execute the already-planned tentative action; free will, it seems is really free-won’t. Thus, there is even a huge question about what constitutes conscious abilities in humans.
The thought that consciousness is governed by the same forces as other evolutionary traits means that improvements that enhance survival and reproduction are always selected for; a higher level of conscious ability is always possible, just as living things better able to deal with physical, chemical, and biological environmental factors out-compete rivals with lesser abilities. The next species to come along, after humans, may have super-conscious ability much superior to our own.
- A. T. Johnson, Biology for Engineers, 2nd ed. Boca Raton, FL, USA: Taylor & Francis, 2019, ISBN 978-1-1380-6789-9.
- O. Güntürkün, “The surprising power of the avian mind,” Sci. Amer., vol. 322, no. 1, pp. 49–55, Jan. 2020.
- L. Chittka and C. Wilson, “Expanding consciousness,” Amer. Sci., vol. 107, no. 6, pp. 364–369, Nov.–Dec. 2019.
Arthur T. Johnson (firstname.lastname@example.org) is a professor emeritus in bioengineering, University of Maryland, College Park, MD, USA.