Human Evolution Process Peculiarities - Essay Example

Human Evolution Process’ Peculiarities Overview Initial classification and taxonomy of the hominids proved inconsistent as more specimens were discovered across the world. It took a considerable duration of time before the arrival at some classification model that could use biological basis of classification based on traits possessed. The Homo class of hominin ancestors was particularly problematic in initial studies since it was at largely referred as the transition class to modern man. Homo erectus evolutionary and adaptive traits from the several species discovered across the world revealed that the synonimization of the systems used to classify hominins would be useful in future analysis. Differences in the various specimens collected from Africa, Asia and Europe could however not quell the need to find the missing link to unraveling modern man origin. According to Anton (2003, p127), further studies on the classification issues involving the Homo genus could offer solutions to the problem. Understanding the adaptive traits of the Homo erectus species and other close hominids assists learners to support or disband independent discoveries surrounding the unraveling of human evolution from primates. H. erectus has been studied to reveal that an important transition occurred to change the entire evolution journey at around the time the hominid existed. Issues have arisen however as to whether the real ancestors of man were from these hominids as well as doubts over the authenticity of the locations where they were discovered. The past two decades have been instrumental in the understanding of the modern man using advanced technology that particularly relies on the DNA technology (Mellars, 2006, p9381). Besides the DNA profiling technology, other innovations adding value to the archaeological work has also been instrumental in the recent past in the evolution studies. Human dispersion theories state that human populations did not move out of Africa until a certain period of time where they then dispersed across the many parts of the world. Using the current DNA profiling techniques, it has been possible to demonstrate that mitochondrial DNA (maternal lineage DNA) can be used to point at possible population explosion that led to the dispersion out of Africa to other areas. The question that arises from such inferences is specifically on the level of resemblance that the dispersed hominids had on each other and the level of resemblance to the modern man. Precisely, modern technology will be used to reveal what stage of evolution each of the specimens was at the time of their death and relationship as maternal lineage studies reveal. The study of hominin movement out of Africa to colonize the rest of the world probably begun during the time of H. erectus and first instance of such postulate can be found in the Eastern Asia region. The finding of a H. erectus specimen in Java at Mojokerto has been used for analysis linking the origin to Africa. Other hominin specimens from Africa have been used for the creation of such links illustrating that the only origin of man should be Africa. Current Evidence of Adaptive Traits of Homo erectus The most profound human evolution events that shaped the rest of modern man evolution destiny took place in the Homo evolution events. The attribute of the early man in terms of gait, size, brain size, appendage proportions as well as behavioral developments needed to pave way for the modern man took place in the Homo events. In almost all of the events, the Homo erectus stage of events has particularly been studied widely to illustrate the importance that the stage had in human evolutionary path (Constance, 2004, p472). Evidence adduced by various studies on Homo erectus and other close Homo genus members from across the world can be used to make a comprehensive analysis on Homo erectus. This study revisits some of the currently acceptable evidence on adaptive traits from across the world with regard to Homo erectus. The main regions with specimens used in the study of Homo erectus include Africa, Western Europe and East Asia. There are a few fundamental discoveries that are associated with the Homo erectus and its close relatives in the evolutionary development. Relationship between the other close relatives such as Homo ergaster, H. georgicus, H. floresiensis, H. antecessor, H. heidelbergensis, H. neanderthalensis, H. sapiens, H. rhodesiensis H. cepranensis is close. The defining attributes such inventions and discoveries would sometimes present a challenge differentiate one form of hominid from the other. Some of the discoveries include the fire, systematic hunting, home bases, tool making and relocation from Africa to other continents. From the Ethiopian specimens’ studies, it is clearly brought out that the tool innovation that Acheulian assemblage brought to evolution happened in this age, at around 1.4 million years a go. Konso Gardula prehistoric site in Ethiopia is the source of the widely studied Acheulian tool assemblage technique which represents an advanced technology in tool making by the early man (Wood, 2005, p124). Tool making at the advanced level would change the lifestyle in many ways. Alternatively, the complexity of the tools made through the technique is a pointer of the higher brain development that could have enabled the conceptualization level required. These tools required an advanced level of cognition, accuracy and precision and arguments have been raised in support of Homo erectus’ predecessor, Homo ergaster as the inventor. The fact that Oldowan tools, a lower technology were invented and used by H. ergaster who appeared after H, erectus. Koobi Fora and West Turkana prehistoric sites of northern Kenya have been on the record for having produced another specimen for H. ergaster, although some researchers have referred to it using different names. Some of the adaptive traits presented by this specimen as recorded include a far more resemblance to the modern man in terms of shape and size than observed in the previous specimens (Finlayson, 2005, p457). The Kenyan specimens exhibited a smaller size of body than the other archaic predecessors. The gait was more upright and relocated from apelike life to more human like lifestyle. Jaws were smaller in size while the teeth fewer and smaller to fit in the smaller jaws. Inferences made from the observations could be used to propose that there was a huge departure from the apelike feeding style and diet composition must have been altered. For instance, it has been postulated that the changes in jaw and teeth parameters could have been occasioned by either changes in diet or processing of the food for instance by cooking it. Reports therefore concluded that there was some link to a routine processing of food by cooking in this Kenyan species. Benot Ya’aqov prehistoric site in Israel have been used to demonstrate a higher level of control of fire by the evolving man at around Homo erectus time. Fires arising from natural occurrences such as spontaneous bushfires and lightning compromised the reliability of early man’s discovery of fire. However, some level of control at later evolution stages highlight the importance that the particular hominid had on the evolutionary history. Control of fire has been demonstrated at the Benot Ya’aqov to illustrate that later hominids were advanced that their predecessors. From Gadeb in Ethiopia, evidence is adduced of some level of control of fire by hominids. The evolution inference made at the Ethiopian evidence of fire control is a classical case of advancement in that baking of stones for various uses at about one and a half million years ago shows some level of sophisticated lifestyle. Similar Ethiopian specimens of fire control have been obtained from Middle Awash Valley, but there are doubts of complete control of fire due to confusion with a bushfire. Habitual fire use in China at Zhokoudian and in France at Terra Amata dating back to a similar period illustrate that the possibility of a more advancement was achieved at the same period (Dunsworth, 2007, p96). Arguments supporting the possibility of early man perfecting his fire usage by moving out of the warm African residence to the temperate regions can be used to support theories postulating that Africa is the cradle of mankind. Many evolution studies’ findings revolved around Africa for certain species and possible reasons raised for the apparent localization was the lack of relocation technology from Africa. Despite there being debates concerning the origin of hominids in some sections of arguments and whether Africa is the cradle of hominids, lack of transport means is the only supportive argument. Alternatively, there are arguments stating that besides Africa, archaeological studies have not extensively been conducted elsewhere. Transport overseas could only have been facilitated by the discovery of the raft, by the H. Ergaster. Dmanisi discovery of tools belonging to the Oldowan culture reveal that possible relocation must have taken place where the hominids relocated with some of their tools from Africa. According to Wood (2005, p86), explaining of the movement from Tanzania to Caucasus can therefore be done by connecting the tools relocation to overseas locations to the discovery of the water transport. The author also presents Ubediya prehistoric site in Israel as a supporting site for the relocation of early man from Africa using water transport. Despite the short stature and relatively small brain size possessed by the H. florensiensis specimen obtained from the Indonesian prehistoric site of Liang Bua, some rare adaptive traits were reported. The use of tools was advanced and polished from the predecessors, which illustrate their importance in the evolution of man. Evidence ahs been adduced to the effect that H. florensiensis were short hominin species about three feet tall. This evidence supports the possibility that they were hunters mainly targeting pygmy elephants at that time. Dwarfism could be analyzed to further reveal the effects of island isolation on other features such as smaller brain size yet remain very sophisticated at that level (Dunsworth, 2007, p95). In almost all cases of specimens preceding the H. erectus hominin, it has been discovered that cranial size was increasing paving way for brain size increase. Increase of brain size commenced from the emergence of H. erectus and continued later to facilitate the emergence of modern man, a study that has widely been undertaken in Encephalization Quotient (EQ) involving hominin evolution. Primate intelligence is said to have had a significant contribution by the emergence of the H. erectus, a fact observed in nearly all excavation results relative to other species (Hartwick, 2010, p77). The general rule is that increased brain size effectively increased intelligence to support the changing way of life for the complex evolving hominids. Gait changed dramatically to an upright posture at around one and a half million years ago to facilitate the complex lifestyle that involved a bipedal posture and the eventual loss of function for the fore arms in locomotion. Increased specialization for the use of limbs particularly promoted the loss of the quadripedal posture and the adoption of the bipedal gait. H. florensiensis specimen obtained at Liang Bua is evidence to the dramatic changes in posture as observed in the hominids near the H. erectus explaining the role of the evolution era that these hominids presented to the entire human evolution. Despite several studies indicating that the evolutionary path for the hominids reveals the origin of man, latest evidence obtained on H. erectus reveal that the hominid was largely more of an ape. According to research by Holden (2004. p472), its dental development is a huge contradiction of a possibility of being the ancestor of modern man. In the findings of this study, the dental development of the hominid resembles that of chimps to a greater degree than it does to humans. Many aspects of development are used in comparative studies between animals with certain similarities such as the hominids. Some of these classification and study elements include reproduction, development and growth. Comparative dental development studies between the modern man and the H. erectus hominid shows that the first molar emerged at an approximately age of four and a half years. Generally, modern man first molar emerges at an average age of about six years while the wild chimps used in this study had an emergence age of about four years. With the acceptance of the fact that hominid H. erectus is an intermediate hominid to man from chimps, the age timing of appearance is more of an ape than it is to the modern man. The brain size however between the chimps, H. erectus and modern man is a pointer of the intermediate role that the hominid plays in evolutionary path. African chimps and an African specimen of H. erectus were used in the experiment. Similar dental studies to unravel evolutionary adaptive traits developed by H. erectus were conducted earlier by Dean et al (2001, p628) using H. specimens obtained from Noriokotome, Kenya and Sangiran, Java. The findings of the study showed that the current dental structure, especially enamel composition of the teeth was developed much later than during the Homo era of evolution. Daily cumulative deposition of enamel across various teeth was studied using thirteen hominid specimens from the said countries. According to the studies, modern man has enamel deposition at a much slower rate than the early Homo species. These specimens were found out to resemble apes dental development processes of enamel deposition. Similarity expectations could have raised the H. erectus higher in evolutionary advancement, to relate well with the finding that the same hominid was more intelligent than the earlier hominids. The fact that the hominid possessed a larger brain size therefore does not place the hominid in a closer relationship to man since the dental differences remain considerably many. Foraging techniques are considered to have dramatically changed with the advancement of way of life as lived by H. erectus. According to studies conducted by Ulijaszek (2002, p518), maximization of food calories by changing the amount of food taken by an individual was a pattern of feeding that was well developed by the H. erectus. This hominid particularly changed the amount of calories taken by cooking food which increased the quantity of consumed because food became more edible. The author of this work confirms that the improved feeding habits enabled the hominid to adopt a better body energy replenishment as well as utilization. Emergence of agriculture must have been facilitated by the changed feeding habits and nutritional sensitivity that the hominids developed. Food availability control was becoming more meaningful during the H. erectus age and has been vital for the rest of the evolutionary path to date. Dental shape and size was to change for the change of diet necessitated the configuration of the dentals system. To back up the point on control of food and changed diet, the H. erectus has been said to be one of pioneers of controlled fire use. Discovery of a specimen obtained in Eritrea at a site called Bula in the year 1998 changed the widely accepted proposition of emergence of modern man’s traits (McDonald, 1998, p18). According to the findings, the remains of the hominid were studied to reveal that the specimen possessed traits resembling both H. erectus and H. sapiens. Inferences made on the specimen clearly pointed out that the modern man’s traits could actually have been possessed by hominids living earlier than expected by more than three hundred years. A breakthrough was in the offing following the Eritrea discovery concerning the origin of H. sapiens. Earlier on there were controversies surrounding the origin of the advanced hominid, bearing in mind that theories of dispersion from Africa had faced criticism. Transition between the two hominids could have happened in Africa as displayed by features such as the paired membrane bone that typical H. sapiens possesses. The possession of the trait show the evolutionary adaptive traits continued to be possessed and developed from one hominid to the other. Further controversies concerning the origin of modern man arose when skulls falling in description of transition between H. erectus and H. sapiens were discovered in Hubei province of China at Yunxian in 1989 to 1990. Conclusion Human adaptive trends accumulated over the entire evolution period, with the different evolution species possessing different traits. The major differences in the hominids between H, erectus and H. sapiens were mainly adaptations that were to accommodate the complex from of life that the evolving man was possessing. According to biogeography and evolution aspects that characterized the environment within which H. erectus lived, the impact of the environment can be analyzed to unravel the evolution patterns of hominids. 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