Overview of The Three Theories About Human Intelligence

Among humans, the term intelligence is a characteristic used to describe the cognitive ability of individuals. Intelligence can be explained as a mental ability to reason, problem solve and learn (1). According to the book, Riveted: The Science of Why Jokes Make Us Laugh, Movies Make Us Cry, and Religion Makes Us Feel One with the Universe by Dr. Jim Davies, humans have, in most aspects, dominated this planet primarily via outsmarting the other species. This paper will examine three theories that seek to explain how humans have become the smartest species on earth from the Social Cognition and the evolution of intelligence lecture by Dr. Davies. These theories are as follows: group living theory, hunting theory and the hand/walking upright theory. Through the examination of these three theories, it will be evident that humanity, as outlined in Riveted, outsmarted other species and that it directly led to planetary dominance.

According to the group living theory, humans became intelligent in order to think about other people. Unlike other primates, humans differ in terms of their social environments and communication. For example, to understand the relation between two people, such as a friend and their spouse, one would need to keep track of all the details in his/her family and their friends. This requires a tremendous amount of mental power since for those who are unable to successfully understand and manipulate the social ties, they would most likely get taken advantage of, outsmarted, and outbred by the ones who could. Therefore, humans evolved to have greater intelligence/intellectual ability to keep track of everyone around them and to build and maintain social relationships. In order to have successful social ties one must be able to effectively communicate. This is the reason why language is prevalent in the human population because without language there’s no proper communication and without communication learning could only happen by direct personal experiences or observations of others. For example, knowing the dangers of entering a certain enemy territory is costlier to learn through trial and error since the learner has a high chance of dying. However, with language, a single individual is able to share the information to more than one person. Therefore, having a smarter brain results in social cognition arms race, which allows humans to develop cognitive skills in order to greater social control (2).

In hunting theory, it states that humans became intelligent due to the processes of hunting prey. Carnivores are much more intelligent in comparison to herbivores. The elusive nature of hunting requires mental fortitude as a carnivore must track, stalk and capture its prey. Whereas in the case of a rabbit, vegetation is not going anywhere. In addition, meat is highly nutritious which contributes to the development of the brain. The hunting theory also supports the group living theory because getting a big kill enables easy socialization. For example, if one goes out and hunted a big wild bull that can feed several people, then that individual is able to communicate and socialize with his/her neighbours to share the food with them. This creates social cohesion among groups that naturally increases chances of survival of the group. Through the sharing of resources, such as food, a stronger community develops and the pressures of survival are distributed among the group such that no single individual bears the sole responsibility of their own survival. Ultimately, this increases the efficiency of the group through the specialization of skills such as hunting, communication and socialization. Through the specialization of skills required to hunt, primarily communication and socialization, individuals became more intelligent.

The hand/walking upright theory suggests that upright walking allowed humans to use hands for various functions, thus making use of more of the brain. Since hands are no longer used for walking due to humans being bipedal, hands have been useful for carrying things, which enable them to generate complex objects with parts from various geographical areas. Therefore, having hands enabled humans to control them better. For example; a dog, who does not have an upright walking posture does not use hands to carry things, therefore they do not need to use much of their intelligence to coordinate their hands for various functions. Due to this their four legged limbs are developed to run. In addition to hands, upright posture also caused the pelvis to be small. The reason why childbirth is painful and dangerous for humans compared to other primates is because of the tension between a bigger head and a small pelvis. Evolutionary having a small pelvis is highly advantageous for female due to the fact that bigger pelvises proved to be challenging for running. In order to deal with and fit through a small canal, evolutionary human babies are born with their skulls in pieces. This is the reason why human babies have soft areas on their heads since the bones fuse after they are born. So how do brains develop without the brain getting bigger? This is because humans evolved to have a general-purpose learning system. Humans are relatively atrocious species, meaning born with little knowledge but with the ability to learn by experiencing the world. In the book Riveted, evolutionary scholars Peter Richerson and Rob Boyd states that humans have the largest brain but are the slowest developing. Due to this, humans have to learn to survive as well as they require parental guidance and nurturing. Therefore, humans adapt to the world that they are born into created by the changes of other people, which results in a positive feedback loop. This means that humans are smart because they make changes to the environment and the children learn from this environment and make changes to it both physically and culturally by themselves.

In conclusion, the reason why humans are intelligent is explained by the group living, hunting, and hand/walking upright theories. These theories are correlated and support each other. For example, being bipedal allows the human pelvis to be small. Simultaneously, this allows humans to use their hands more freely. The ability to use hands to create weapons or tools is highly useful for hunting and so forth. Ultimately, it is clear that physically, humans are not impressive in terms of overall strength, speed and stamina in comparison to other animals whom have evolved to specialize in these areas. However, in the case of intelligence humanity is certainly the dominant species.