Bipedalism Essay

The time interval that I analyzed this animal was from 11:30am to 11:50am and this monkey actually had a very active behavior and it was really a good experience to observe this monkey. The immediate physical description I was able to analyze from this primate was that it was black with a very long tail that later I was able to find out that it was actually a prehensile tail. The common behavior in this one was much walking and sitting during my analyzation. It was interesting to see the locomotion of this animal because I was able to see that it was both Quadrupedal and Bipedal. From the knowledge I have gotten from this class I know having that is a great advantage especially for the fact that it even uses it’s prehensile tail because it means they can travel for a much longer time compared to the primates that have only the locomotion of a quadrupedal. During my observation there was a point where the monkey was just prone on the cage and I thought it was almost going to pee on me because its genteel parts became very red so I stepped away from the cage. The primate at no time peed during my observation so that was a relief.

All animals with limbs have a common design. If a batwing were to be formed from a person’s hand, make the fingers extremely long; a horse elongates the middle fingers and reduce and lose the outer ones; frogs elongate the bones of the leg and fuse several of them together. All in all, despite radical changes in what limbs do and what they look like, this underlying blueprint is always present.

Accompanied by fossil experts Fred Mullison and Bob Masek, the author discovered a fish with a wrist, and another with a part of a fin, and part of a limb. They worked to relate the structure of the fin/wrist joint with its function for the fish. Titaalik had shoulder, elbow, and wrist shapes composed of the same bones as the upper arm, forearm, and wrist in humans. With pectoral muscle scars and crests, the author could conclude that the fish could do “pushups”. Considering the rest of the animal, with its flat head, top eyes, and ribs, the fish was built to navigate the bottom of streams and ponds, avoiding larger predators in the water. The interesting hypothesis coming from this evidence is that many of the major bones humans use to do different functions such as walk, throw, and grasp came first from other ancient animals. Yet, these bones similar in structure to their ancient counterparts come together to create a unique construction in the present. Characteristic of this construction include our ability to rotate our thumbs relative to the elbow, leading to hand usage, as well as the hind limbs with knees and elbows in opposite directions, leading to bipedal

For many animals, the ability to move is essential for survival. Animals move for a variety of reasons such as: to find food, a mate, a habitat to live in, or to escape predators. It is important for animals to develop new abilities and traits to accomplish these necessities of living. Natural selection has shaped the locomotion methods and mechanisms used by moving organisms for millions of years. Generally, non-human primates are studied to garner an understanding of evolution caused by natural selection because of the many distinctive adaptations that have occurred within their taxonomic order. To understand the origin of locomotion that exist amongst primates, the two categories of primates must be analyzed to recognize morphological trait differences. Then, three major determinants can be evaluated to describe the variety of locomotor patterns primates display: the ecological niches in which the primate originates, the current inhabited niches, and the major key aspects of survival such as

Primates have been evolving for millions of years and during this time they have adapted into ecosystems in which they live in. Through the process of primate evolution, the most significant impact was their changes in body structure and locomotion. Evolution is the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth. Improving body structures and speed of movement made it possible for the primates to escape predators and survive hostile environments. Throughout the Epoch of Cenozoic Grades, primates developed four different types of locomotion in order to adapt to the new environment.

The skeletal characteristics of these hominines suggest that their mode of locomotion was likely a cross between occasional bipedalism and obligate bipedalism. From the reading we have learned that obligate bipedalism is bipedal locomotion that is practiced all of the time while occasional bipedalism is bipedalism that is practiced on occasion. The ratio of arm length to leg length (longer arms) suggests that they did spend time climbing trees, however the cranial and post cranial traits of these fossils suggest that they spent much of their time on the ground and likely ambulating bipedally combined with a variation of upright walking and knuckle walking. This is evidenced by two factors: the fact the foramen magnum of the skull is centrally located, and the ratio of arm to leg length. In creatures with bipedal ambulation, the foramen magnum is located in the center of the base of the skull to keep the head aligned over the center of gravity of the creature. If the fossils were walking primarily with their knuckles, the

2 Modern hominins possess extremely large brains relative to body size and are bipedal, however the former trait shows up late

The first behavior, locomotion, is well known for hominins because of the evolution to bipedalism. Bipedal locomotion allows for the carrying of objects, provisioning family, and efficiency of energy, among many other reasons. Not all primates are bipedal. Chimpanzees can walk both bipedally and quadrupedally. They have been a common point of reference for a better understanding of the evolution of bipedal locomotion in early ape-like hominins. Many studies have looked into the evolution of walking quadrupedally to bipedally. These bipedal performances of contemporary non-human primates have given important context that can help in reconstructing early hominin bipedalism. Many anthropologists claim that biomechanical models link locomotor performance to anatomy and have the potential to reveal robust form function relationships, however, this is only given to the extent that locomotor performance of chimpanzees and other species are shown to fit

Bipedalism was the first evolutionary change to define the hominid lineage. It was a major evolutionary change that changed the way we move. Bipedalism is the condition of using two feet for standing and walking. Before bipedalism emerged we were walking on all fours just as many animals do presently. Bipedal locomotion dates back to 7 million years ago with one of the candidates which is Sahelanthropus tchadensis. The other two candidates for the earliest bipedal hominid are Orrorin tugenesis, and Genus Ardipithecus. This evolutionary change brings about several benefits such as being better adapted to live on savannas, having freed hands, more efficient for travel, and better regulation of body temperature. However, similar to many evolutionary changes, Bipedalism comes with “costs” or disadvantages. These disadvantages include our loss of speed, and more stress on lower body joints including the spine.

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

Each toe was surrounded by a durable pad on the bottom and sides and ended in a small, pointed hoof. However, it was when the Eohippus that its entire weight was held by its fourteen toes, allowing the powerful muscles in its legs to propel the Eohippus forward. The tiptoe style of running allowed the Eohippus to reach greater steeds while conserving more energy. Over the next several thousand years, several changes can be observed. By the Obligiocene era, the Mesohippus was nearly identical to its ancestor except for the front limbs, which lost one toe each, and the size. The Mesohippus is often recognized as the first being in the Equidae family to show a significant increase in size. With only three toes on each foot, the increased weight was mostly distributed to the middle toe. The descendants of the Mesohippus, including the Merychippus, showed little change in the structure the foot. However as time passed, there is evidence that more weight was placed on to the middle toe. The first one-toed ungulates have been seen as far back as fifteen thousand years ago. These beings had evolved in such a way that only vestigial structures remained of the

Main Article: 'The Advantage of Standing Up to fight and the Evolution of Habitual Bipedalism in Hominins'

Peter, 103). Thus, bipedalism of living hominids is considered to be more efficient than quadrupedalism (Rodman, S. Peter, 104). The morphology of locomotion is often a comprise with other dimensions of existence (Rodman, S. Peter, 105).

These two models provide insights into how bipedalism evolved from quadrupedal type of locomotion. Though the arguments are supported by numerous evidences, there are actually still a lot of things need to be explained, and they all seem to have something in common, which is to ensure the continuity of the

Homo erectus was considered close to Homo sapiens or the modern man because of their body anatomy that allowed them to stand and walk upright (Castro). Another notable characteristic was the appearance of long legs and arms in the proportion to the torso that resembled the features of the modern man. According to scientists, these features mean that they had lost their ability to climb trees and were living on the ground, unlike their predecessors (Gauthier).