Bipedalism is one of the most common traits used when identifying what distinguishes what a human is. However, humans are not the only species that exhibit this trait. There are numerous species besides humans that exhibit bipedalism that are currently living or that have become extinct. Bipedalism has been an important trait for humans and their past ancestors since bipedalism is a very primitive trait that has evolved quite some time ago. Currently, there is no specific answer as to why bipedalism emerges but there are numerous hypotheses and these hypotheses will be examined in this paper. This paper will also identify the different signs that indicate whether or not a species is bipedal. First of all, it is important to define what bipedalism …show more content…
There are numerous key identifying factors that are used to determine whether or not a species is bipedal. One easy way see signs of bipedalism is to look at the length of the arms in proportion to the length of the legs. According to Walker and Shipman “primates that habitually climb in the trees have longer arms than legs, while bipeds and leaping primates have longer legs than arms” (131). This is an easy way to see if a species is bipedal. Another way of determining bipedalism is by locating the position of the foramen magnum. The foramen magnum is a hole in the skull where the spinal cord connects passes through in order to connect to the brain. In quadrupeds, species that walk on all fours, the foramen magnum is located towards the back of the head. In bipeds, the foramen magnum is located towards the bottom of the skull. This is important because it allows bipeds to look forward and maintain posture when they are walking upright. This position is often used to classify hominins as bipeds when the skull is the only bone available as seen in the previous example of the species known as Sahelanthropus tchandensis. Ultimately, the most indicative traits that can be used to determine bipedalism is by studying the actual parts of the body that are involved in walking upright. In bipedal humans and hominins the iliac blade has been shortened and is bent. The bent iliac produces a bowl shaped …show more content…
With the evolution of bipedalism the arms are freed up to do other things since they are not needed for walking anymore. One of these things is the creation and use of tools. Tools can be used for a variety of different things like gathering food or cutting objects etc. Charles Darwin proposed a positive feedback loop where bipedalism leads to the creation of tools which leads to a more reliance on bipedalism. This hypothesis is okay but it has some problems. Chimpanzees can use tools, but they are not bipeds. Also, bipedalism can be dated as 1.7 million years older than the oldest stone tools. However, the fact that bipedalism and tool use are somehow connected cannot be ignored so this hypothesis has some validity to it. Another hypothesis is the connection between bipedalism and energy efficiency. In Humankind Emerging by Bernard G. Campbell, James D. Loy, and Kathryn Cruz-Uribe it is stated that humans walking at a moderate speed is more energy efficient than other quadrupeds moving at the same pace. Further studies of human and chimpanzees have shown that human bipedalism is more efficient than chimpanzee quadrupedalism. The conclusions of these studies can be used to conclude that in hominin evolution energy efficiency was a trait that was selected for that helped lead to the evolution of bipedalism (242-243). Another possible reason as to why bipedalism evolved has to do with bipedalism and body temperature. A
The evolution of man is constantly in question. While we are reasonably sure that modern humans and primates are both related to the same common ancestor, there is constant debate over what initially caused the two species to split into early hominids and apes. According to some, our longest and most popular theory on the division of man and ape is profoundly wrong. However, those same individuals usually offer an equally controversial theory as a substitute, one that is almost impossible to scientifically test or prove. Both the Savanna Theory and the Aquatic Ape Theory offer solutions to how and why humans evolved into bipedal toolmakers. But with enough questioning, each loses its accountability to rhetorical science.
Bipedalism (our ability to walk on two legs), the uncommon size of our brains, symbolic language, and the ability to farm/hunt is what makes us different from the past era. (Christian 6-7) Pages 1-22 begins the era of foragers, also known as the “Paleolithic era” where they use stick and stone tools to survive across different climates around the globe. The era of foragers is the longest (250,000 years) and the hardest era to integrate evidence because of the time gap. Christian stated, “Historians have had a hard time integrating the era of foragers into their accounts of the past because most historians lack the research skills needed to study an area that generated no written evidence (2).
Humans are not the only species with the ability of making tools. Early on in her research, Jane Goodall observed an older male chimp, she called him David Greybeard. Through her observation of David, she witnessed two forms of the use of tools. The first was the use of grass as a tool to extract termites from their mounds. The second was the making of a tool by stripping the leaves off a twig, modifying it for the same purpose. When Louis Leakey heard this, he wrote her “Now we must redefine tool, redefine man, or except chimpanzees as humans” (Goodall, 2002). There is a definite correlation between man and chimps in this respect. Human culture involves learned behaviors through observation, imitation and practice, the use of tools with chimpanzees show the same ability for learned beh...
After analyzing the remaining family group, their appeared to be a difference in size among the discovered fossils. Johanson claimed that all the remains found belonged to one species; however, other anthropologists and scientists disagreed and believed that two or more were from different species. The analysis of Lucy’s knee joint indicated that cranium, mandible, dentation and postcranial skeleton contained unique characterizes, which resembled in a large degree the ones in a human being, and also indicated bipedal locomotion. After analyzing the remaining family group, their appeared to be a difference in size among the discovered fossils. Johanson claimed that all the remains found belonged to one species; however, other anthropologists and scientists disagreed and believed that two or more were from different
After millions of years that humans separated from their relative primate how is that humans became bipedal. So many changes have happened to the human body to decide to stay on the ground and abandoned their lives in the trees. Primates evolved different body structures according to their lifestyle and the ecosystem in which they lived. As Charles Darwin natural selection stays; it could be as a result of new environments, the need for food and shelter, which forced humans to adapt and survive. Although, most of primates’ anatomy reflects habits of movement, it could be easy to see the external differences but there are many differences that have been intensely studied and researched.
If Shipman is correct and humans evolved from animals that were primarily scavengers, previous explanations for human evolution would have to reviewed and compared to the new evidence. Current understanding of the development of bipedalism as an evolutionary advantage would change. Standing upright would be considered an advantage to finding carcases for scavaging, instead of a predatory reason. This small change in our understanding of human ancestors, would change how human understand themselves. Shipman uses tool and teeth marks on bone and early hominid's physical biology to support her claims.
Australopithecus afarensis existed between 3.9 and 3.0 million years ago. The distinctive characteristics of A. afarensis were: a low forehead, a bony ridge over the eyes, a flat nose, no chin, more humanlike teeth, pelvis and leg bones resembled those of modern man. Females were smaller than males. Their sexual dimorphism was males:females; 1.5. A. afarensis was not as sexually dimorphic as gorillas, but more sexually dimorphic than humans or chimpanzees. A lot of scientists think that Australopithecus afarensis was partially adapted to climbing the trees, because the fingers and toe bones of the species were curved and longer than the ones of the modern human.
Many factors could have played a part in the evolution to bipedalism. Some of these are adaptation to environment and the need to have free hands to handle tools and weapons. These factors were the basis of Charles Darwin's theory of the evolution of quadrupeds to bipeds. (Hawks). Advantages of bipedalism include the ability to see farther and wider distances because you can see from a higher vantage point; the ability to carry food, tools, and weapons; and more efficient movement.
The fibula is a leg bone located on the lateral side of the tibia, with which it is connected above and below. It is the smaller of the two bones, and the slenderest of all the long bones, and plays a significant role in stabilizing the ankle and supporting the muscles of the lower leg. The fibula is the smaller, non-weight bearing, of the two bones in the lower leg, while the tibia is the larger, weight bearing bone. The fibula and tibia moves very little relative to each other and the joints that it forms contribute significantly to the function of the lower leg. The joint it forms permit the fibula to adjust its position relative to the tibia, increasing the range of motion of the ankle. Fibular fractures are not often a severe injury, because the bone is supports only about 17% of the body weight.
Bipedalism is anatomically important because it now demonstrates to us modern day humans the cycle of how we came to be. This skill was vital to human evolution because it differentiates early hominins from apes. By being able to walk further distances, they brought them to a diverse new diet that enabled their brains to get bigger. Bipedal animals usually walk greater distances because less energy is needed with their longer strides. The stone stools show evidence of abstract thinking and it shows the early hominins adapting and using their environment to survive, which is a skill that we as modern humans have surpassed.
“The scientific study of how humans developed did not begin until the 1800s in Europe. Until that time, people relied on religious explanations of how humans came into existence. Starting in the 1500s a scientific revolution began to sweep Europe. Thinkers started using scientific methods and experiments to try to better understand the world and the creatures living in it. Eventually these methods were turned to the question of human origins” (The Nature Of Human Origins, 1). Earth made it possible for species to change over time because Ancient Earth provides ability to plenty of time.The Homo Sapien a is very complex creature. The species started off very simple by living in caves and surviving with little food and then later evolved into a species that were able to do many more complex things. The first species was Sahelanthropus tchadensis They were one of the most simple humans in that time period and on. They had very small skulls compared to Homo Sapiens today and their motor skills were just the same. We have evolved and changed for the better both mentally and physically. The Evolution of Homo Sapiens started off simple, such as the Neanderthals, and now we are the most advanced species to ever walk the planet so far.
Throughout the long winding road that is human evolution; many species have helped shape who we are today. There was the early Australopithecus africanus which began to walk bipedally-upright with two feet and the Homo habilis which drastically developed the construction of handmade tools. But there is one species who is to be credited for the most critical advancements in human evolution; Homo erectus. Not only did Homo erectus advance us the most biologically, but also the most geographically.
The members of the Homo genus possess a combination of unique features that distinguish them from other related species. At the time that each respective species was alive, they were able to walk upright on two legs, use their large brains for the benefit of their species, and could thrive in many geographically and climatically diverse areas of the world. One of the most mysterious quandaries in science is how the lineage of the Homo genus became so different from their primate relatives. Bipedalism, brain size, and location diversity all have a common link that may explain this difference – dietary evolution allowed humans to adapt to their surroundings, and in turn, become a more advanced species. The Homo diet evolved in relation to food availability and nutritional necessity. With the ability to maintain a proper diet, the species of the Homo genus were able to flourish and advance toward the development of modern Homo sapiens.
One of the most important and pivotal physical and biological adaptations that separate humans from other mammals is habitual bipedalism. According to Darwin, as restated by Daniel Lieberman, “It was bipedalism rather than big brains, language, or tool use that first set th...
The evidence for human evolution begins with the australopithecines. All the australopithecines were bipedal and therefore possible hominines. In details of their teeth, jaws, and brain size, however, they modify enough among themselves to be divided into five species: Australopithecus anamensis, A. afarensis, A. africanus, A. robustus, and A. boisei. Genus Homo are also divided in five different spices: Homo erectus, H. habilis, H. sapiens, and H. sapiens sapiens.