Australopithecine Comparison

accommodate this strange position, we have developed a specialized pelvis, hip and leg muscles, and an S-shaped vertebral column. Because these changes can be documented in fossil bone, bipedalism is seen as the defining trait of the sub family Homininae.

The changes in morphology that resulted from selection for bipedalism included a readjustment of the pelvis and changes in the major locomotive muscle attachments. Habitual bipedalism necessitated a reduction in the gap between the sacroiliac joint and acetabulum, with a reduced sagittal breadth. Though the pelvis of early hominids differs from that of modern humans, but still had the traits necessary for habitual bipedalism. The Australopithecine pelvis is more similar to humans than to chimpanzees (Lovejoy, 1988): The blade of the illium is longer and wider in chimpanzees than in Australopithecus or Homo. This obvious difference is due to the functions of the pelvis in each species’ body, like being a weight bearing bone versus. Australopithecus afarensis, particularly Lucy, had a mosaic of anatomical traits featuring both human and apelike features. The short pelvis and broad iliac blades which curve around the side forming the area of gluteal muscle attachment confirmed that Au. afarensis was at least a habitual biped (Lovejoy,

Ardipithecus has been discovered, an Ancestor that dates back prior to the remains of Lucy. In the article written by Ann Gibbons and others, it dives into the discovery of our most ancient ancestor and the clues given to us from all 110 remains that have been found of A. ramidus. First let me begin with Lucy whose remains were found in 1974 and that dated back to 3.2 million years ago. These skeletal remains gave us the evidence needed to prove that our ancient ancestors were bipedal before evolving their big brains. After Lucy was discovered the scientist found themselves with even more questions, such as, were any previous ancestors before Lucy bipedal or did

Extinction: Most species become extinct because they can’t cope with the environmental change, and also because of introduced species that turned into competitors for

Discoveries relating to the human lineage are extremely exciting and often baffling. This is the case with the recent discovery of what seems to be the oldest member of the human family. A skull found in northern Chad in 2001, has been deemed the earliest relative to the human ever found. Nicknamed Toumai, and discovered by Michel Brunet and his paleontology team, this new category of human has been given the scientific name, Sahelanthropus tchaensis. What makes this skull so definitive is the fact that it dates back approximately 6-7 million years in the earth’s history (Whitfield 2002). Since the discovery there have been anthropologists and paleontologists that have

Afropithecus is a fairly large extinct ape- 50kg, characterized by a lack of a prehensile tail, long snout with procumbent incisors, generalized limb proportions and thick molar enamel. The braincase of Afropithecus is fairly small in size compared to other Miocene apes and Old World Monkeys from the same area. The primitive characteristics of Afropithecus suggest a relation to early catarrhines- such as Aegyptopithecus. And the post-cranial fossil record suggest that it was both arboreal and quadrupedal, similar to the proconsul that Afropithecus is categorized

Each and every primate’s exhibit changes for climbing trees and shrubs and has evolved into two major groups: Prosimians and also Anthropoids.

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.

Approximately 4 million years ago a wonderful evolutionary phenomenon was happening in Africa. Early hominids, man’s ancestors, were beginning a giant leap in their evolution. These hominids were moving out of the forest and beginning to walk upright, out on the open plains (Fagan, 98). This change from quadrupedalism was the most significant adaptation that ever happened to these early hominids. It caused many adaptations that make man what he is today. This process occurred in early hominids for many different reasons, each reason helping to perfect the upright walking posture. Bipedalism is thought to have occurred because of changes in environment, feeding habits, thermal regulation, and

The discovery of Ardipithecus Ramidus (Ardi) changed our whole insight of how humans evolved. The theory that we evolved from ape like species was disproven. Because of Ardi’s has close resemblance of qualities of both a chimpanzee and a human, she is thought to be the “missing link” between our last common ancestor and the Australopithecines. Ardi’s had a pelvis structure, which was evident that she was bipedal on the ground while she could also climb trees, using her long fingers and opposable big toe for grasping, however the flexibility that apes use to grab and scale tree trunks and vines she lacked. The way the hand, wrist and shoulder bones demonstration shown that she wasn't a knuckle walker and did not spend much time hanging or swinging

it's the oldest celebrated skeleton of an individual's relative. The individual is believed to be a feminine and is nicknamed ‘Ardi’. She weighed regarding 50kg and stood regarding 120cm tall.The skeleton was in very poor condition and it took the team fifteen years to excavate, scan, build virtual reconstructions, assemble and so analyse. The results we tend tore massively vital in terms of however we read the evolution of the earliest hominins and also the physical look of the last common relative of humans and chimpanzees. The skeleton doesn't look very similar to a great ape or pongid or have the expected 'transitional' options. Instead, it's going to well preserve a number of the characteristics of the last chimp-human

The overall stature of Australopithecines compared to of that of Paranthropus, is smaller. Based on the estimates of Johanson and Edgar, 2006; Jungers, 1988, I created a table (Figure 1) illustrating the size of both genera. The average weight of a male in the genus Australopithecines is 43 kg and for Paranthropus is 44.5 kg. The average weight of a female in the genus Australopithecines is 29.5 kg and for Paranthropus is 33 kg. The average male height for Australopithecines is 1.45 m and for Paranthropus it is 1.35 m. The average female height for genus Australopithecines is 1.10 m and for the genus Paranthropus it is 1.15 m. Both genera have sexual dimorphism, where the females are of smaller stature and weight. This type of sexual dimorphism

One of the most intriguing aspects surrounding this topic is the multiple different hypotheses for the evolution from quadrupedal gait to bipedal locomotion. Due to the fact that evidence suggests that the emergence of bipedalism occurred as early as 6 millions years ago, there have been many hyptotheses as to how the earliest hominids

Male Australopithecines are on average 4’11” and weigh about 94 pounds while females average 3’5” and weigh close to 64 pounds. The most notable characteristic of Lucy was found in her knee, which indicated that the species walked upright or was bipedal. Lucy’s limb proportions also provide insight to her bipedality. Human’s hind limbs (legs) are longer than their fore limbs (arms). The ratio between arms and legs is called an intermembral index. The average intermembral index for humans is between 68-70”, while chimpanzees fall around 106”. Lucy’s intermembral index is 88”, which falls between both. This suggests that A. afarensis probably walked on the ground with hind limbs and climbed in trees with fore limbs. Lucy’s pelvic blades are human-like in that they are short and curved forward, making the case for bipedality while on the ground. The location of Lucy’s shoulder, however, provides insight that she spent time climbing in trees. Furthermore, Lucy’s sacrum is wide and short at the top and goes in laterally like in humans. A wider and shorter sacrum is better for distributing weight through the pelvis. This follows with bipedal theories because this shaped sacrum is better

The human foot is an example of micro-evolutionary and macro-evolutionary changes. It has had to adapt to bipedal walking and the stress that is caused by being upright. To identify changes in the human foot; comparative, molecular, and biocultural approaches and their paradigms are used. Therefore, different, and cumulative approaches are needed to make informed hypotheses in biological anthropology. The foot will be shown as an example of approaches commonly used and the resulting perspectives in biological anthropology.