The question of human and animal evolution
Evolution has become a topic of popular and controversial debate within the last two-hundred years. Beginning with modern day examples of Colleen and Jane, we are able to see the complex ways in which humans currently communicate. There are claims that state humans are the most socially and cognitively advanced of any other species on Earth today because of our perceived evolutionary outcomes. Many believe that these claims are supported by neurological and biological evidence of human social cooperation and decision-making juxtaposed with other species using the same human-centered criteria. However, humans might not be the most cognitively and socially advanced creatures on the Earth.
The evolution of pre-homo sapien and modern day human social cooperation
Humans cooperate for numerous reasons. However, what seems to be unique about human cooperation is that humans have the capacity to move past one another’s differences in order to survive. One example of this can be seen in American politics, where humans are able to congregate and compromise in order to move forward and not only survive, but continuously aim for “progress.” Globally, it is interesting that organizations like the United Nations bring countries together from all over the world, despite conflicting beliefs and ideologies, in the pursuit of common goals.
To illustrate a more specific example of how powerful human social cooperation is, let’s propose that Colleen is involved in a group project at her job that takes weeks of work and coordination. When the project is finished, Colleen and her team will present it as part of a bid for a $1,000,000 contract- the biggest bid ever in the history of her company. While this work is mostly enjoyable, Colleen has occasional differences with her coworkers. Colleen and her team present the bid and end up winning the record-breaking contract. In this instance, Colleen’s disagreements with her coworkers are outweighed by the successful contract bid and its benefits.
However, levels of cooperation vary in humans. Jane, who is extremely uncooperative, has grown up in a household where communication was not very effective, and the family never worked together to overcome differences and barriers. Jane has developed a negative association with social cooperation due to her experience as a child.
The differences between the two females’ stories can be explained with the nature versus nurture argument. Those who side with nature say that genetics are the primary reason for an individual’s actions. Those who side with nurture say that our environment is the determining factor of our thoughts and actions. According to Dr. Dwight Kravitz at George Washington University, along many other experts, this argument is no longer up for debate as one’s development is influenced by both nature and nurture, and possibly even more factors that we do not yet know about.
Now that we have analyzed social cooperation with modern day humans, let’s examine pre-homo sapien cooperation and evolution. Recent evidence shows that historical and forensic anthropologists have been able to reconstruct possible social norms in pre-homo sapien societies where various species of hominids lived. Cooperation is one aspect of human activity that has seemed to remain constant even before humans crossed “the line” from Australopithecus to homo. Cooperation is an act that can be socially observed amongst organisms, including animals and humans, on a biological, or what I am coining the genotypic, or social/physical basis. However, one could argue that these forms of cooperation are not the same. Not even in the case of humans versus pre-humans could one argue that cooperation has remained the same over time in the contexts of purpose and complexity. Provided that we assume early humans have more “primitive” instincts, we see how the need for cooperation might also be more primitive, like the instinct to mate or hunt, compared to modern day cooperation, such as the passing of legislation in government, or cooperative group projects. Given this type of argument and the result of the nature versus nurture argument, the question that arises is, how does the need for cooperation initially arise?
A neurological basis for evolution of social cooperation
While Colleen’s case may show how cooperation can be reinforced on a phenotypic level meaning can be physically observed-it can also be studied on a biological level with the dopaminergic system in the brain. As Kravitz states, “the dopamine system is entwined in a loop wherein positive signals are sent into the limbic and prefrontal systems, producing emotion/memory and training reward, respectively.” When dopamine is released into the brain, a reward signal can be produced of varying degrees. In Jane’s case, if dopamine is the primary neurotransmitter that is responsible for reward signals, what happens when the production of dopamine has ceased, or decreased temporarily, due to a malicious event or circumstance, as in the case of Jane. This break in dopamine is responsible for the creations of human aversions, fears, worries, and so on. In the case of Jane, the negative association of cooperation due to the repeated breaks in dopamine when attempting to cooperate with her family as a child has caused her to likely not have the motivation to cooperate. Further, we can see that cooperation can be observed on a neurological level in modern humans like Colleen and Jane as “recent experiments that focused on the effect of partner strategies explored differential activation in the dorsolateral prefrontal cortex (DLPFC) when playing with human agents who were cooperative, neutral, and non-cooperative […] and found activation in the superior temporal sulcus as a function of successful adaption to reciprocal/non-reciprocal strategies of computer agents […].”
It may be the case that some people simply produce less dopamine, or that they have less dopamine receptors for dopamine reuptake.
A study on cooperation and competition, conducted by the NIH, shows that “cooperation is a socially rewarding process and is associated with specific left medial orbitofrontal cortex involvement.” It is interesting to note that the orbitofrontal cortex is also heavily involved in the signal of reward which ultimately generates motivation. These natural events are cyclical and have varying effects on peoples’ behavior. According to W. Schultz, “a cooperation between the different reward signals may assure the use of specific rewards for selectively reinforcing behaviors.” There is evidence that cooperation is reinforced when it produces rewards. Whenever a positive result emerges from cooperation, it is likely the case the neurotransmitter, dopamine, is released. When this happens, everything leading up to the action is reinforced. It is uncertain what the exact dopamine levels of pre-homo sapiens were, so the neurological analysis of Colleen and Jane better explain the cause of modern day human cooperation. While there are many cases like Jane’s that oppose the general outcome of this kind of reward system, we know the most general modern human population is like Colleen.
The amygdala is an important bran structure in the study of human cooperation. The amygdala is believed to be relevant in terms of social behavior and is “shown to be necessary for acquiring Pavlovian fear conditioning, but it also turns out to be important for learning to fear a stimulus merely by observing another person experience its consequences[…].” A decreased amygdala is argued to be associated with a decrease in fear within criminals. However, there has been scarce brain imaging research on the amygdala and no evidence suggesting which regions within the amygdala may be structurally compromised in individuals with psychopathy.
Now, what does this mean for our study of early humans? Of course, we do not have any physical brains of early hominids to measure and analyze. However, based upon the measurements of the cranial remains we have been able to find, we can estimate how large certain brain structures might have been. Furthermore, we are also able to analyze the brain structures of modern day primates. The brain size and skull shape of Australopithecus resembles that of a chimpanzee; however, we do not know the exact weight, or “cranial capacity.” According to the Smithsonian National Museum of History, the “average weight of adult chimpanzee brain [is] 384 g (0.85 lb)” whereas the “average weight of modern human brain [is]1,352 g (2.98 lb).” Given the data, we can see that changes in the size of the amygdala could be associated with increased cognitive capacity in social cooperation over the course of human evolution. Moreover, this means that the increasing size and capacity of all relevant brain structures can be associated with increased, or advanced, social cognition and cooperation.
The human superiority complex
While many may support the idea that human cooperation is indeed unique in a way that makes them superior to other organisms, the evolutionary history of the parts of the brain that are responsible for all types and processes of cooperation might show us the exact opposite. Humans are not cognitively and socially superior because of their ability to carry out complex social tasks, or engage in complex social activities like politics. There are animals with bigger brains than humans, and if increased brain size is associated with increased social cognitive capacity and cooperation, the evidence from the evolutionary history of animals with larger brains suggests that other animals, such as dolphins, might have increased capacity for cooperation. The frontal lobe is extremely large in dolphins, a species that has outlived humans for millions of years. The frontal lobe plays a massive role in social cognition and cooperation. If increased size of the frontal lobe means higher socially cognitive capacities that allow for advanced cooperation, perhaps dolphins are neurologically and cognitively superior to humans. Human are not superior because the dolphins don’t debate politics and play chess. We are only able to digest the world around us through the limited senses we have. Our vision is often skewed by our inherent biases as human. Because of this, we cannot always be confident in our assumptions of causal relationships within the world. As humans, we have a tendency to categorize, and humans, like many other species, also tend to stick together as a group. As a result, we exclude things from our group that are unlike us, often things with characteristics that we do not understand, and make assumptions about the world based on how we perceive the world through our biased lens. As human technology develops, and we are able to study animal biology in more depth and with greater understanding, we may uncover the hidden intricacies of the animal minds we have labeled as inferior. However, we will always struggle to quell the superiority complex most humans are subject to.