Austalopithecus Afarensis: Evolutionary Analysis

Humans evolve from apelike ancestors approximately five million years ago. Most closely related to us are our non-human primates such as African great apes, chimpanzees and gorillas. Scientific studies reveal that more similar traits are being share by human and our non-human primates compared to other animals. As human evolve from our apelike ancestors, changes in our DNA differentiate ourselves from our non-human primate. Even though we evolve from our non-human ancestors and share similar anatomical structures and characteristics, we are unique in our own ways. We possess specific qualities and abilities that differ from other species. There is a substantial gap between non-human primate and fully developed human. Here we will discuss

Homo erectus was first found in Africa and the fossilized remains dated 1.8 and 1.0 million years old. The Homo erectus traits are very similar toward the modern human traits. Homo erectus brain size was smaller than the Homo sapiens. Homo erectus had a brain size of approximately 650 cc and Homo sapiens had a brain size of approximately 1251

We share almost 99 percent of our genetic material with chimpanzees. Yet we have several traits that are very different. Two legged walking, or bipedalism seems to be one of the earliest of the major hominine characteristics to have evolved. To

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,

In the Article “Redrawing Humanity’s Family Tree” by John Noble Wilford, describes how two different skulls challenge the theories of human origins and migrations. The Central African skull, that dates back to nearly 7 million years ago, was assigned to a whole new genus and species because of its apelike and evolved hominid species. The 1.75-million-year-old Georgian skull shows evidence that the first hominids may have been intercontinental travelers who set motion the migrations that occupied the whole planet. Finally a third skull was found that is the same age and shares a resemblance but, the size of the skull suggests that the brain was smaller than expected for H. erectus.

Figure 6 shows a selection of mammalian skulls. The primate skulls are the two on the right and as you can see, they have relatively short snouts. Obviously there is a huge amount of variation in gross skull shape across the mammalian class, but certainly, on average, primate skulls tend to be short. Elaboration of the visual apparatus, with the development of varying degrees of binocular vision. Orbits ringed with bone. Figure 6 also shows the characteristic morphology of the primate orbit. The eyes face forward for binoccular region, the eyes tend to be quite large, and the orbit is either a fully enclosed cup (as in the chimp in figure 6) or a lateral post-orbital bar (as in the aye-aye). In most other mammals (for example the bear and kangaroo), the eye is simply plastered onto the side of the skull and held in place by soft tissue.

Michel Brunet and his team found the fossil in the sand dunes of northern Chad after “a decade of digging”(Whitfield 2002). This discovery is most definitely a new one and one that will cause the reinterpretation of all previous hominid research. What makes this find so spectacular is that the structure of the skull suggests a being that walked upright, though it lived in a time when apes and chimpanzees also existed. “Sahelanthropus has many traits that shout ‘hominid’. These include smaller canines, and thicker tooth enamel than apes. And the point at the back of the skull where neck muscles attach suggests that Toumai walked upright”(Whitfield 2002). The key to this discovery, Brunet believes, is the back of the skull that suggests a muscle attachment for upright walking ability, which supports the scientist’s theory that

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

A recent discovery of four fossil primate teeth from the species Afrasia djijidae of the late middle Eocene Pondaung Formation of Myanmar has stirred up the debate of our primate origins. This new finding suggests that members of this clade originated in Asia then dispersed to Africa sometime during the middle Eocene, shortly before their first appearance in the African fossil record. Afrasia Djijdae is morphologically similar to Afrotarsius (North African Anthropoid). Afroasia’s dentition is very similar yet more primitive to Afrotarsius. After these phylogenetic analysis the two anthropoids have been deemed

The evidence shown refers to the fact that they were both part of the same Australopithecus ancestors. However based on brain size to body weight and the shape of muzzle angle and skull shape both share distinct similarities to man and whether only one or both were direct ancestors is still a moot topic. Based on evidence collected Homo erectus shares more similarities to Homo sapiens then that of Homo ergaster (sharing the same dimensioning of the Nasal Opening, cheek Bone, the Post orbital constriction (for exact dimensions refer to table above)) The brain sizes are also remarkably similar the Homo erectus having a brain capacity 69% of Homo sapiens. Based on this evidence it is concluded that Homo erectus is placed as an earlier ancestor evolved from that of Homo ergaster, despite the two living in very similar time periods.

Despite this, they were very similar to ours. Endocasts from Neanderthal skulls have shown very similar frontal lobes, so much so that it’s difficult to tell the different between a Neanderthal and modern Homo sapiens one. 3-D images of a Neanderthal skull is low and elongated, unlike our which is dome-like. This could possibly show the shape of the brain. Also, some parts of the Neanderthal brains were smaller than ours, such as the parietal and temporal lobes, which could have an impact on their cognition, especially regarding language, memory, and spatial

From Proconsul heseloni, it was decided that three species evolved from it. These species included A. A. afarensis, A. africanus and Sivapithecus indicus. Sivapithecus indicus was branched off the early human evolutionary line as the characteristics from the dentation and skull characteristics differed from that of A. afarensis and A. africanus

Australopithecus was said to have features that were both human like and ape like. Their brains were said to be significantly smaller than hominids and were more in the range of brains for modern apes. (Australopithecus: Definition, Characteristics & Evolution. 2016. Australopithecus. [ONLINE] Available at: http://study.com/academy/lesson/australophithecus. [Accessed 17 November 2016].)

Human evolution is the gradual process in which people, or Homo sapiens, originated from apelike ancestors. Scientific evidence, particularly in the form of fossils and secondary remains, show that the physical and behavioral traits shared by all people evolved over a period of approximately six million years. Humans are primates. Both genetic and physical similarities show that humans and the great apes (large apes) of Africa, chimpanzees (including bonobos, or so-called “pygmy chimpanzees”) and gorillas share a common ancestor that lived between 8 and 6 million years ago. The volume of fossils found in Africa suggests that most evolution occurred there and is likely the place of origin for early humans. This brings to fruition the “out of Africa” theory, also called the “single-origin hypothesis.”

Human evolution according to research started over 6 million years ago. The outcome of the evolution process is the current human beings. Scientific studies have revealed over the years a remarkable affinity between the chimpanzees/Apes and human beings. Even though this reality is not a definitive prove that human beings evolved from apes, it does show that the human beings are in one way or another related to other primates. Scientists suppose that the humans and the primates shared a common ancestor. The subject of what makes humans what they are and their origin has been the exclusive purpose leading to many scientific studies globally (Coolidge & Wynn, 2011). Studies believe that Africa was the origin of evolution millions of years ago. Fossil remains have been discovered in different parts of Africa as well as other regions of the world. Different hominins have been discovered around the world in the last 1 million years. Thus, the different discoveries have led to comparisons between the various species of hominins to clarify on their similarities as well as differences. This essay seeks to explain whether they were distinctively different species or regional versions of the same species.