No Neocortex, no problem. An examination of intelligence in non mammalian species.
One characteristic that has consistently separated humanity from the rest of the animal kingdom is the presence of intelligence. Humans are intelligent and animals are not. This has been the most decisive division between humans and animals in the body of scientific works in the past. Intelligence is often considered to be a distinctly human quality present because of the presence of the extremely complex structure of the neocortex in the human brain. Although this structure is present in all mammals it is (relatively) the largest and most complex in humans. However, recent studies are beginning to demonstrate that intelligence is not a trait that is limited to mankind, even animals that do not have a neocortex, such as birds and octopi, have demonstrated intelligence. Thus, where does intelligence come from? It seems that “…the human brain contains no highly conspicuous characteristics that might account for the species’ cleverness” (Dicke, 2008). Therefore it is possible that intelligence may not be linked to any one physical structure in the brain but could be evidence of a non-physical aspect to thinking and problem solving.
In order to argue my case convincingly I must first present a definition of intelligence based on measurable qualities. “Certain skills are considered key signs of higher mental abilities: good memory, a grasp of grammar and symbols, self-awareness, understanding others' motives, imitating others, and being creative” (Morell, 2008). There is also the ability for an animal to learn and devise new solutions to existing problems. (Dicke, 2008). Thus, my definition of intelligence is the presence of memory, creativity, self-awareness, learning and/ or empathy in an organism. This can be demonstrated through social or altruistic behavior or through scientific experiments.
Examples of animals demonstrating intelligence are becoming extremely common in scientific literature. “Scrub jays know that other jays are thieves and that stashed food can spoil; sheep can recognize faces; chimpanzees use a variety of tools to probe termite mounds and even use weapons to hunt small mammals; dolphins can imitate human postures; the archerfish, which stuns insects with a sudden blast of water, can learn how to aim its squirt simply by watching an experienced fish perform the task” (Morell, 2008). Across species, intelligence is no longer being ascribed to only humans and nonhuman primates. More and more, intelligence is recorded in unconventional species such as parrots. This example comes from the work of Irene Pepperberg who worked with an African Grey Parrot named Alex to determine whether parrots could only imitate speech or if they were capable of human-like reasoning skills. “[Pepperberg] then retrieved a green key and a small green cup from a basket on a shelf. She held up the two items to Alex's eye. "What's same?" she asked. Without hesitation, Alex's beak opened: "Co-lor." "What's different?" Pepperberg asked. "Shape," Alex said” (Pepperborg, 2009). To return to the list of traits indicating intelligence, this example demonstrates memory (remembering the words to be said), learning (being capable of knowing the answer) and empathy (having an understanding of the other individual/ understanding what you are supposed to do).
This is not an isolated case, in my own life I too own an African Grey Parrot who is named (somewhat ironically) as Happy. Happy has an abrasive temperament and often delights in picking on the different people and animals that also live in my home. One day, I observed Happy calling one of my dogs into the room by calling the dogs name, whistling and saying loudly “treat”. When the dog obediently ran to the room and sat in front of the cage expecting a dog treat Happy imitated my little brothers laugh then resumed eating. This alone demonstrates memory (recalling how to call the dog), and recognition of other organisms (when the dog in question arrived Happy stopped calling for him), and recognition of a verbal symbol (a laugh) as an appropriate marker for the successful prank. To add to this instance, the dog in question recently died and Happy has stopped calling his name.
So if “brains and intelligence are a universally shared trait in nature” (Pepperberg, 2009), is there one part of the brain that is constant between them that could account for this? Can it be argued that the neocortex is the source of this intelligence in all of these animals? If that was true then the neocortex in humans, which is extremely complex and relatively large compared to the birds discussed earlier, must be especially demonstrative of this intelligence. “…the size of the cortex constitutes no better arbiter of a superior mind. The same is true for the prefrontal cortex, the hub of reason and action planning. Although some brain researchers have claimed in the past that the human prefrontal cortex is exceptionally large, recent studies have shown that it is not” (Dicke, 2008). The neocortex is then not dependent on size for a high level of intelligence but, the lack of a complex cortex should still prove to be a hindrance to higher thinking, right? “Bird brains, it was said, don’t have such a cortex. Hence, their cognitive capacity should be extremely limited” (Pepperborg, 2009). But, as it has been demonstrated above, it is not. Thus, the neocortex must have far less to do with intelligence then has been previously theorized.
There is one way in which humans differ from animals and have, thus far, proved exclusively adept at; language. This has allowed humans to excel at advanced learning and solving “social problems,” “Hare defines a "social problem" as the ability to watch somebody else and figure out what they're trying to do — and what they want you to do” (Neighmond, 2007). Animals are adept at many things but their ability to grasp language and grammar is extremely limited. Most animals develop to the approximate equal of a two-three year old child but can not exceed that limit. “This timing corresponds with the development of Broca’s speech area in the left frontal lobe, which may be unique to humans” (Dicke, 2008). The only difference between the development of human and animal intelligence is thus the presence of this area in the brain, which is lacking in animals. So, when it comes to “adding, counting, remembering where something is hidden” and other puzzles, animals can rival humans in their level of skill (Neighmond, 2007). But, when it comes to learning through language humans do have a distinct physical advantage. Still, this indicates, not a lack of intelligence in that area, but a physical limitation on the ability to form a language. It seems the lack of a neocortex in birds and other species has led to this problem of language and nothing more.
Based on my research and personal observations I would say that animals possess a high degree of intelligence that matches that which is found in humans. If this were connected to the physical structure of the brain you would expect birds and humans to have similar nervous systems. As this is not the case I am forced to conclude that a purely physical description of the brain is not adequate to explain all of the processes of the nervous system. The presence of intelligence in animals lacking a complex neo-cortex is evidence for a non-physical structure beyond the physical brain that plays a large role in the development of intelligence. This also indicates that this non-physical mind is present in both humans and animals. So, if humans and animals can both think and act on those thoughts what truly separates us from the rest of the animals?
Dicke, Ursula, and Gerard Roth. "Animal Inteligence and the Evolution of the Human
Mind." Aug. 2008. Scientific American. <http://www.sciam.com/article.cfm?id=intelligence-evolved>.
Hauser, Marc D. "Morals, Apes and Us." 1 Feb. 2000. Discover Magazine.
Klinkenborg, Verlyn. "What Do Animals Think?" 1 May 2005. Discover Magazine.
Morell, Virginia. "Animal Minds." Mar. 2008. National
Neighmond, Patti. "Toddlers Outsmart Chimps in Some Tasks, Not All." 7 Sept. 2007.
Pepperberg, Irene M. "Think Animals Don't Think Like Us? Think Again." 20 Jan. 2009.
Discover Magazine. <http://discovermagazine.com/2009/feb/20-think-animals-dont-think-like-us-think-again/article_view?b_start:int=1&-C=>.
Lastly, for an example of invertebrate intelligence watch this video of an octopus opening a bottle at http://www.youtube.com/watch?v=wfRqYjv9QgA