Evolutionary Traits of Humans and Gorillas

Species behavior has the potential to trigger the morphological evolution. This statement is true for both humans and gorillas. The behavior of all species can potentially be deduced from their morphology. The cognitive gap between humans and other species seems to be large. Humans undertake complex activities, wage wars against each other, and communicate effectively. The unique human cognition is down to the evolution of the human brain. Compared to other species humans have a large brain size (Dunbar & Shultz, 2007). This allows them to engage in activities and behave in a way that other species cannot. The evolution of human beings is characterized by an expansion in the brain size. The human brain is several times larger than that of a primate of a similar or even bigger body size. The development of language is a unique human cognition that arises from the brain. Humans have more developed language skills partly due to a highly evolved and developed brain. This ability is only limited to humans (Barton, 2004).

            Walking upright or bipedal locomotion is one of the defining behaviors of humans. It is the hallmark of human evolution. Bipedal locomotion gives a great advantage to humans. It improves visual access to far away distances and allows humans to manipulate tools and weapons. By evolving into an upright walking position, humans were able to carry babies around, make tools and throw weapons. Bipedal locomotion freed the arms to carry and manipulate tools. It also allowed for more endurance and ultimately long distance walking and running. The morphological traits that enabled upright walking include a plantar rigidity or simply a flat foot. This allows the foot to remain flat after every single step. The configuration of the spine, pelvis and the manner in which the femur bone fits into the pelvis explain why humans walk upright or engage in bipedal locomotion. The human vertebrae is organized in such a manner that allows the body to distribute weight down to the pelvis.

            However, bipedalism is not an effective technique of locomotion for gorillas. Their bodies are suited to the quadruple knuckle-walking style. In comparison to humans, they have much longer arms than limbs. The vertebrae is also not suited for even distribution of weight. Gorillas have distinctive morphological traits that enable knuckle-walking. Their radius and wrist bones interlock to bear a lot of weight during knuckle-walking phase. Gorillas are by any measure big in size and heavier than humans (Barton, 2006).  This morphological trait assists Gorillas to bear their weight and move around more effectively. Their remarkable body size gives them the strength to tear through vegetation in the process of finding food. In fact, gorillas are the biggest primates in the world (Barton, 2006). An adult gorilla consumes an average of 25 kilograms of food every single day. As mentioned before, the arms of gorilla are longer than their limbs. This allows them to rest their massive weight on the arms while knuckle-walking. The skeleton is also suited to bear their massive weight. In comparison to humans, their spines are straighter enhancing the ability to bear a lot of weight. 

             Typical of the primates, gorillas have developed brains sizes, but not as developed as the human brain. Their skull is big enough relative to the size of their bodies. Their well-developed brain structure allows them to communicate by way of facial expression, grunts, screams and barks. Gorillas have unique dentition that is suited their eating habits. For instance, they have a large crest within the teeth adapted to breaking down tough vegetation. The big sagittal crest helps to support the jaw muscles during chewing. Just like humans, gorillas have 32 teeth that aids in chewing, grinding and cutting.

            There are primary factors that have defined the evolution of primates over the years. These factors include:

Socialization

            Primates are typically social animals. It is commonly believed that primates evolved their social nature due to the need to protect themselves from predation. At the same primates have evolved into increasingly violent and aggressive creature due to competition for limited resources. Most primates are organized in social groups. These allows them to coordinate activities, mate easily and communicate effectively. They maintain strong social bonds compared other creatures (Kappeler & van Schaik, 2002).

Unique traits

            Most of the living primates have arms and limbs with four digits, including opposable thumbs. These unique physical characteristics allow them to hold food and tools. Unlike other animals, primates have very flexible hip, shoulder, and limber joints, allowing them to swing on branches and climb up and down effectively.

            The primate brain is one of the most unique and distinguishable evolutionary factors. The olfactory area in primates is greatly reduced while the cerebrum is expanded (Barton, 2006). The region of the primate brain that coordinates with stereoscopic vision is well developed in comparison to other animals.

            Evolution has shaped different species in unique ways to cope with the demands of their habitats and their feeding habits. Primates have evolved almost similar characteristics over the course of millions of years. These characteristics are quite unique from those of the other species in the animal kingdom.

References

Kappeler, P. M., & van Schaik, C. P. (2002). Evolution of primate social systems. International journal of primatology, 23(4), 707-740.

Dunbar, R. I., & Shultz, S. (2007). Understanding primate brain evolution. Philosophical Transactions of the Royal Society of London B: Biological Sciences, 362(1480), 649-658.

Barton, R. A. (2006). Olfactory evolution and behavioral ecology in primates. American Journal of Primatology: Official Journal of the American Society of Primatologists, 68(6), 545-558.

Barton, R. A. (2004). Binocularity and brain evolution in primates. Proceedings of the National Academy of Sciences, 101(27), 10113-10115.