Human Evolution Essay

In the article “Born to Run” by Adam Summers, who is an assistant professor of bioengineering and ecology and evolutionary biology at the University of California, Irvine, the author states that throughout time bipedalism has evolved to benefit endurance running. Summers also claims that bipedalism modern humans have differs from the one our early ancestors had. The author relies on the research by Dennis M. Bramble and Daniel E. Lieberman that have improved the understanding of human bipedalism and its evolution. According to Summers, the corrections made by Bramble and Lieberman’s research helped to draw a more accurate picture of an early human.

Based on Chapter ten from the textbook, there are seven distinct differences of a bipedal hominin like us humans, and a quadrupedal pongid, such as a gorilla (Larsen, 2014). One of the seven steps include the length of the leg, shown in humans to be long which gives us proficiency when striding or running unlike apes that have long arms for climbing on trees. A second step is the opposable big toe found only in apes that give them the capability to take hold of objects and walk. A third step of the seven is the position of the foramen magnum, which in humans is on the bottom of the skull while in apes it is in a posterior position. Overall, the difference is found in that the human head rests on top of the body while the ape head sits in the front. Lastly, a fourth step is the shape of the spine. Humans have an S-shape and apes have an almost C-shaped. Humans have numerous curves to assist in maintaining balance when standing up.

The Australopithecine are some of the earliest known hominids and they embody many characteristics that are associated with bipedalism. Bipedalism is a highly specialized and unusual form of primate locomotion that sets modern humans apart from all other living primates as we are the only extant obligate bipeds. Many evolutionary biologists and paleoanthropologists have devoted innumerable research hours to attempting to understand this unique form of locomotion and how it evolved. A number of interdependent morphological adaptations occurred over a long period of time to solve challenges posed by habitual bipedalism. As a result, there are obvious differences that exist between early and late hominin species.

Bipedalism is being able to walk on two feet. Bipedalism separated the hominids from the four legged apes. It has allowed us to travel far distances, distances that four legged species couldn’t even travel.Hominids had a much better advantage when it came to traveling on rocky and grassy terrains. Also, walking upright made fleeing from predators much easier, because on four legs an animal is most likely to die. There were also drawbacks to for instance a female hominids pelvis is narrow, so delivering a baby would be very painful and life threatening to both child and mother. Other than the advantages and disadvantages of bipedalism, these are the key things that

The book identifies “Lucy” as an ancient demonstration of bipedalism and a bowl-shaped pelvis. Her species, Australopithecus afarensis, had both ape-like and human features. The adaptations she exhibited are an example a further branching off of species. Aside from bone structure, I found it logical that early hominids

Walking upright with two legs is a common daily phenomenon, however, the ability of moving with only two legs is the result of millions of years of evolution and adaptation. During the process of human evolution, the appearance of bipedalism, which describes the terrestrial locomotion where animals move with their rear limbs in the form of walking, hopping or running, is considered as one of the major steps that sets Hominin group apart from other primates. Even though the transition from quadrupedalism to bipedalism has major drawbacks that sacrifice the flexibility and prevent bipeds to effectively practice arboreal locomotion, it provides a new form of locomotion and frees both hands to be capable of completing other projects while

Human evolution was one of the most believed theories that explained how humans were created. As time progressed, so did the humans. However, there were many differences between modern humans and the prehistoric man which includes the capacity to think, larger brains, and a longer life expectancy. The prehistoric man had to survive on their own for the most part like finding food and shelter. Life for prehistoric man was not easy due to the harsh environments they had to live through by creating weapons, tools and communities.

One of the earliest ancestors of homo sapiens that are known of is the tchadensis which is a member of the genus Sahelanthropus. The S. tchadensis is a primitive human that lived about 7 million to 6 million years ago, it is believed that they lived in areas that would require walking on two feet such as grasslands, as a result the S. tchadensis had the ability to partially walk on two feet. As time went by the S. tchadensis evolved into the tugenensis, which is a member of the genus Orrorin. The main difference between the S. tchadensis and the O. tugenensis is that the O. tugenensis developed two femur bones which are used for walking on two feet, the O. tugenensis was around from about 6 to 5.8 million years ago. The third genus in human evolution came into existence about 5.8 million years ago and was named Ardipithecus, this genus has two known members kadabba and ramidus.

There are abundant existing theories of how bipedalism developed into a lasting attribute of hominines. The anticipated origins for the transferal to bipedalism incorporate theories such as heat dissipation, accomplishment in mate attraction, and food gathering (Chadda, 2006). The theories are all extraordinary and remain seemingly credible purposes for why bipedalism may have allowed for early hominids to have a grander chance at advantage and survival. Nevertheless, it is my belief that it was not one solitary reason as to why hominines begun to walk as bipeds, but instead a force of numerous of these origin models that allowed the hominine an advantage over his survival, and the eventual creation of an obligate biped.

Bipedalism, a locomotion that consist of the two lower limbs to move. This can be found in many animals, but it is considered more “optional” than “mandatory” as a way to transport. Some use it as a defense mechanism. In humans, it is one of the special characteristics that is used to differentiate the human species from the rest of the Hominidae family. Only humans have “mandatory” bipedalism. Other characteristics include massive brain size and the ability to make and use tools (Lovejoy,1988). It was discussed that because of going from quadrupedal to bipedal it cause many advancements such as brain development. Bipedalism was the biggest evolutionary change for the human ancestors. Nobody really knows the origins of bipedalism, but there are some theories that might explain it. It can be the freeing of hands to use tools or to hold and carry resources or offspring. It can be change of habitat from woodland to plain or use of defense mechanism to look beyond the plains for predators at further distance. It can also be energy efficient and to run longer more easier compare to quadrupedalism. Bipedalism gave many advantages with the change of human body, mainly the skeletal structure, but is it possible that some of these changes have tradeoffs? Some scientists believe that certain illnesses, injuries, and health complication are the results of the change of skeletal structure to become bipedal. There are disadvantages for bipedalism and it can differ between male and

There has been much debate concerning the origins of bipedalism. Bipedalism, or the ability to move on two legs (eLucy, 2007) was said to have emerged due to climate change in East Africa, for sexual display purpose, to reduce exposure to sunlight, the need to use weapons and tools and many more (NOVA, 2013). There are numerous arguments associated with bipedalism as no one can be entirely sure as to what constituted to the emergence of this trait, which was first present in hominins Australopithecus Afarensis. Anthropologists claim that there is a missing link in the evolutionary lineage that makes it hard to confirm the real cause of bipedalism emergence. However, there are some models which are widely accepted by scientific world, such

One of the hypotheses show that bipedal mutation might caused by hairless mutation which separated the early chimpanzee to hairless human and hairy chimpanzee lineages. (Sotou 2012). Based on the behaviors of apes or monkeys, the babies attach themselves to their mother by grasping the mother’s hair, therefore the female apes or monkeys could use their hands to climb or walk (Sotou 2012). On the contrast, hairless mutation has to force the mothers to use their hands to carry their baby due to the baby has nothing to grasp, thereby compelling the mothers to stand upright (Sotou 2012). During the transform, hominins gained the opportunity to divide their forelimbs from quadrupedal locomotion to evolve some human behaviors and increasingly enhance the dexterity of hind limbs (Sotou

What evidence shows the changing from the early hominids to the modern humans? Throughout the human evolution body parts like legs and harms have changed for the better. By the early hominids being biped, meaning they are able to stand and even walk on two feet, it helped them to be able to do more things like getting around more and help with their tool making and hunting. A lot of the fossils discovered were found in the Great Rift Valley in East Africa, which contained many different lakes and small rivers. For many years researchers have been finding new species. These species have been named Australopithicus, robust australopithecines , Orrorin tugenensis, Homo habilis, Homo erectus, neanderthal, and Homo sapiens. These early

While I was walking around the Human Origins exhibit, there were several pre-human skeletons that I found very interesting. This includes Lucy, Homo erectus and Neanderthal. The first skeleton model is Lucy. About three million years ago, Lucy is one of the earliest hominids that lived in Eastern Africa for a very long period of time. It was revealed that Lucy had a wide and short pelvis and thigh bones, which explained why she was able to walk with two limbs instead of four. The second skeleton model is Homo erectus. They originated from Africa, but left for China and have lived for more than 1.5 million years. One common characteristic that they have with Homo sapiens is the way they look and walk. Homo sapiens had been evolved from Homo

Observing a comparatively large arm length to high ratio in respect to humans, anthropologists are able to determine this species was also arboreal. Taking into account a cranial capacity of 430cc - 485cc, we are able to deduce that these hominins are in a developmental stage between humans and apes. Their facial feature shared similarities with both early apes and modern humans. The raised zygomatic arches and prominent brows suggest a closer relation to apes than homosapians. Whereas with humans gender hardly affects height or appearance of skeletal structure, with this species, sexual dimorphism is incredibly prominent. The males were very noticeably larger than the females. This makes differentiating between the two far