Significance of Neandertals to the Evolution of Anatomically Modern Man - Essay Example

Significance of Neandertals to the Evolution of Anatomically Modern Man The origin of modern man and its relationship with Neandertals has been a topic of great debate in the field of paleo-anthropolgy (Mellars 35). In the past, it was supposed that the Neandertals were the less developed ancestors of modern man. However, new archaeological evidence seems to suggest that in fact the Neandertals competed with modern man for thousands of years in Europe before they eventually disappeared (Hardy et al 45). The modern archeological debate is the question of the role that Neandertals played in the evolution of anatomically modern man. Neandertal fossils date back to 130 000- 30 000 BP throughout the region of Eurasia. Their fossils were morphologically different from modern man in that they were ruggedly built with thick chest (Lahr 130). The Neandertals were very strong and muscular; an adaptation that helped them to survive in tough conditions. According to Hublin, the Neandertals spent most of their lives in caves given that their reign was during a period of long glacial maximum. Although referred to as ancient cavemen, recent archaeological studies have pointed out that the Neandertals were intelligent considering the fact they used stone tools and sometimes fire. (Ponced et al,13767). Thus, new evidence suggests that although the Neandertals were slightly physically different from the anatomically modern man, both shared a lot of characteristics. According to Roebroeks, anatomically modern man came into direct contact with the Neandertals about fifty thousand years ago (p. 438). The neandertals and modern man were forced to compete for the resources available like food and locations (Mellars 103). However, the highly specialized morphology of the Neandertals began working to their disadvantage due the climatic changes. There is no conclusive evidence to ascertain whether modern man was more evolve than the neandertals at this point in history. However, the discovery of cultural items associated with early modern man suggest that indeed, neandertals were less evolved in comparison (Hardy 35). Since both the neandertals and modern man shared diets, the competition for food grew fierce with time. Eventually, the neandertals were pushed towards harsh and less fertile environment which heralded their demise. It should be noted that modern man and neandertals were very similar. Research by Currat pointed out that modern man and neandertals had similar cultures (p. 15129). For instance, both were cognizant of the significance of death and tools of trade were inherited. Although they both had had significant morphological differences, their genetic distinction could still allow for mating to produce offspring that was viable. The possibility of interbreeding between modern man and neandertals may offer insight into the similar traits between the two (Weaver et al 464) . The gene of microcephalin is archeologically attributed to neandertal man. This trait was absent in modern man genome up to approximately one million years ago. Its presence in anatomically modern man thus points out to interbreeding with the neandertals. The gene that allowed for more brain development and intelligence was critical for the existence and survival of modern man (Ponced 1365). This gene was rapidly propagated through the modern man by positive selection and it is now present in a majority of the world population. Thus, it is evident that neandertals passed on some superior genes of brain development to modern man which contributed significantly to their evolution. The intelligence gene was advantageous to the progress and survival of anatomically modern man in a dynamic world. According to Blow et al, further research into the DNA of Neandertals has indicated compellingly that in deed anatomically modern man and neandertals interbred (1367). This conclusion was reached after the study found out that modern man had a gene that helped to develop resistance to virus that was previously found in neandertals only. Human leukocyte antigen was found to be present only in modern man of European origin. This would be attributed to the fact that ancient anatomically modern man migrated to Europe which was inhabited by the neandertals. The neandertals had a strongly developed immune system and thus passed it on to modern man. The gene was critical in ensuring that the new immigrants were protected from the diseases that had not existed in their homelands (Blow et al 1350 Mellars 85). Notably, the mating of neandertals and modern man helped in passing on the antigen that protected modern man from viruses and parasitic worms that never existed in their regions of origin. Advances in fossil dating technologies and DNA sampling have provided a great opportunity for the investigation of the relationships, if any, between modern man and neandertals. Scientists have been able to isolate neandertal genomes and evaluate their genetic compositions (Ponced 13768). However, there has been significant resistance to acceptance of the interbreeding theory between the anatomically modern man and neandertals. One of the theories to this effect postulates that perhaps anatomically modern man and neandertals did not interbreed but were subjected to the same selective pressures and modern man triumphed. The shared traits between them might have been due to having a common ancestor. However, Currat refuted this shared ancestry concept due to the fact that the alleles found among in neandertals and the people of Eurasia were not present among people of continuous African descent (15129). Essentially, this means that if modern man and neandertals had a common ancestry, then the alleles would have been common to all anatomically modern man. More evidently, the alleles that contribute to immunity can only come from the immune system being subject to the conditions in Europe for lengthy of periods of several thousands of years (Weaver 45). Shea argued that modern man adapted much better to the ecological and selective pressures of the time much better than neandertals (39). The period that marked the existence of both modern man and neondertals was coldest phase in the history of Europe. Neondertals were morphologically adapted to the warm climate due to muscular nature. Thus, the intense cold climate was unfavorable for them and this led their eventual extinction. Also, Mellars observed that the neandertals may have had inferior technology as compared to the anatomically modern man (125). This implies the neandertals lacked the technology to enable them to survive in the sub zero temperatures of winter time. Hence, they were limited to survive in warmer areas and when they were pushed to the colder areas, extinction was inevitable. However, the anatomically modern was of s slightly smaller build and had technologically advanced mechanisms to deal with the cold climatic conditions (Hardy and Moncel 46). In the end, anatomically modern man survived the harsh conditions of the lengthy cold period. This theory offers a plausible explanation for the disappearance of most but not all Neandertals due to the fact that some would have lived in warmer areas. However, Roebroeks disputes this theory due to the fact that it overly relies on the assumption that neandertals were technologically challenged to survive in the harsh cold climate (452). Archeological studies show that neandertals were capable of making tools using stone and they would draw on cave walls. Thus, the wholesale assumption that they technologically challenged may not hold water (Lahr and Fohley 154). It is possible that the anatomically modern man had the ability to adapt to the harsh cold conditions through cultural dispositions rather than relying on natural selection. In essence, the behavioral attributes may have played a significant role in the evolution of modern man while neandertals perished (Hublin 180). The modern man had agility that would enable them t have better mobility than the neandertals. Anatomically modern man was able to move from place to place as the climatic conditions changed whilst the neandertals were seemingly tied to their habitat permanently. On top of this behavioral advantage, the immigrant anatomically modern man had the advantage of sheer numbers. The neandertals had a small population hence continuity was not guaranteed in the case of a disaster (Mellars 112). Due to their large population, anatomically modern man was able to have division of labor. This ensured that they were not overwhelmed by the daily chores and hence preserve their energies. The women and children would also engage in only light chores or rest. This division of labor and reduced responsibilities for women helped in ensuring that modern man’s survival was not threatened. In the long run, the neandertals were exposed to higher risks and their survival chances were greatly diminished. The scientific community has different and sometimes contradictory views on the issue of neandertals and modern man evolution. Some believe that neandertals were a different species from the human race and that they did not interbreed with anatomically modern man (Shea 35). According to this school of thought, they became extinct due to failure to adapt to the climatic changes and also the interaction with human beings. Eventually, they were replaced by anatomically modern men who were emigrating from Africa. Other scientists are convinced that neandertals were part of the human species and they disappeared after breeding with the ancestors of modern man. Finally, they are scientists who believe that neandertals are ancestors of anatomically modern man. One of the major challenges that face the DNA and fossil investigations in regards to neandertals is the issue of sample size. The numbers of fossils that have been found by archaeologists are just a small percentage of the population the existed then (Pounced 2008). Thus, the fossils just represent a tiny portion of the population implying that there analysis may not be a true representation of the real characteristics of the population. The sample sizes do not provide the confidence level that can be termed as conclusive. In order to attain convincing information, a large sample is necessary. Therefore, the current interpretations are subject to adjustments until there is a sufficient sample size. The use of DNA analysis to analyze the impact of neandertals is also subject to restraint. This is because the relationship between species cannot be judged based on only the numerical levels of similarity of their DNA sequences. This is because the main determinant of genetic characteristics is determined by the control genes (Weaver 50). Thus, species can have almost similar DNA sequences but only a small part of the control genes can create a huge difference between the two species. Contextually, it is plausible that although anatomically modern man and the neandertals’ DNA sequence are almost a pure a match, the small difference in control genes may imply vast differences between them. In conclusion, it is necessary to appreciate that most studies tend to be inclined towards a species- separation theory of the evolution of anatomically modern man and neandertals (Weaver 14, Blow et al 1351). The present archeological data point convincingly to the fact that neandertals and anatomically modern man co-existed at a certain point in human history. The question of the duration of this period is subject to various interpretations among scientists (Currat 15129). However, it is clear that the neandertals disappeared and the evolution of modern man continued. There are many similar characteristics between anatomically modern man and neandertals. These include similar cultures, use of tools and genetics. The fact that anatomically modern man possessed some genes that were once exclusive to the neandertals is a pointer that neandertals played a significant role in the evolution of modern man. Although there are still doubts whether anatomically man interbred with neandertals, it is understood that the neandertals impacted significantly in the evolution process of modern man (Hublin 161, Shea 33).Advances in technology and further investigations of the fossils will definitely shed more light on the actual role of neandertals in evolution of modern man and perhaps overhaul the current knowledge. Works Cited Blow, M.J, Zhang, Woyke T, Speller CF, Krivoshapkin A, Yang DY, Derevianko, and Rubin EM. Identification of ancient remains through genomic sequencing. Genome Res 18 (2008): 1347–1353. Print Currat, M & Excoffier, L, ‘Strong reproductive isolation between humans and Neanderthals inferred from observed patterns of introgression’, Proceedings of the National Academy of Sciences, vol. 108, no. 37 (2011), pp. 15129-34. Print Hardy, BL & Moncel, MH, ‘Neanderthal Use of Fish, Mammals, Birds, Starchy Plants and Wood 125-250,000 Years Ago’, PloS one, vol. 6, no. 8, (2011) p. e23-68. Print. Hublin, J.-J. in The Geography of Neandertals and Modern Humans in Europe and the Greater Mediterranean (eds Bar-Yosef, O. & Pilbeam, D.) (2000)157–182 (Peabody Museum, Harvard Univ., Cambridge, Massachusetts). Print Lahr, M. M. & Foley, R. Towards a theory of modern human origins: geography, demography and diversity in modern human evolution. Yb. Physical Anthropol. 41, 127–176 (1998). Print Mellars, P. A. The Neanderthal Legacy: an Archaeological Perspective from Western Europe Princeton Univ. Press: Princeton, New Jersey, 1996. Print Shea, John. Modern Human Origins and Neanderthal Extinctions in the Levant. Athena ReviewVol. 2. (2011). P. 21-44 Ponced,Leon MS, Golovanova L, Doronichev V, Romanova G, Akazawa T,Kondo O, Ishida H, Zollikofer CP.. Neanderthal brain size at birth provides insights into the evolution of human life history. Proc Natl Acad Sci 105, (2008):13764–13768. Print. Roebroeks, W 2001, ‘Hominid behaviour and the earliest occupation of Europe: an exploration’, Journal of Human Evolution, vol. 41, no. 5, pp. 437-61. Weaver, TD, Roseman, CC & Stringer, CB. ‘Close correspondence between quantitative-and molecular-genetic divergence times for Neandertals and modern humans’, Proceedings of the National Academy of Sciences, vol. 105, no. 12 (2008) p. 46-65. Print Read More