Assignment Writing Help on Hominine Species

Hominine Species Name: Institution
     
Hominine  Species The hominin species is believed to have diverged from the ape lineage approximately 7 million years ago. Hominin species is used to refer to bipedal species that relate closely to man. Close to two million years ago, there appeared considerable differences in earliest hominins. Scientists and anthropologists have taken the difficult task to establish the origin of the early man and the stages of evolution drawing references to the archeological deposits, artifacts, and fossil records. Though the evolution process took long, it is evident that the ancestry of the modern man belonging to the hominin species can be best explained by the use of the evolution theory.  

Pleistocene ecological conditions that contributed to selection for the genus Homo.  

According to Smithsonian (2015), evolution of humans came about as a result of adaptations arising to respond to environmental instability. Survival became fully dependant on the adaptation features rather than being fit. Through research, paleoanthropologists have given several proposals of how environmental conditions stimulated developments in the origin of humans. Several species came to being through the evolution with different adaptation features. Some of these adaptation features include walking with an upright posture, making tools, brain enlargement, longer periods for maturation and complex mental and social behavior and dependence on technology (n.p).  The evolution of man coincided with the environmental conditions, such as cooling, drying, and climate fluctuations through time. Environmental conditions varied greatly in the later stages of human evolution as compared to the earlier stages of evolution (Smithsonian 2015, n.p). Longer time scales of environmental change influenced the change of hominins due to the shifts in temperature as well as precipitation causing great changes in vegetation. This included migration from grassland areas and or areas with shrubs to woodland regions and forests and or from cold climate areas to warm climates. Stony Brook (2009), explains that each global climate transitions were accompanied by reduced North Atlantic deep-water formation and ice rafting from both Greenland and Antarctica. Ice expansion and cooling in either hemisphere would have significantly increased the pole equator thermal gradient leading to another and or southern compression of the inter-tropical convergence(p.154). The hominin environments were also affected by tectonics such as earthquakes and uplifts, which would eventually change the general topography of a region. Moreover, Stony Brook (2009), says that the uplift of the Ethiopian and Kenyan plateaus resulted in changes in orography and associated rain shadow believed to be the main driving force for increased variability of availability of moisture throughout eastern Africa (p. 154). Smithsonian (2015) says that activities such as volcanic eruptions as well as forest fires disrupted food availability water, shelter in addition to other resources. Such changes lasted for so long raising the instability and uncertainty of the survival of most organisms. For this reason, these organisms had to adapt to these ecological changes in order for them to survive.  

Population pressures and ecological factors that contributed to the dispersal of the genus Homo.

Habitat preferences that would involve particular kinds of vegetation or favorable temperature and rainfall would lead to these hominins moving to get to their preferred habitats or preferably opt for genetic change to their new habitat. In the absence of these two options, an organism is doomed to extinction. (Smithsonian, 2015, n.p). The genus homo also experienced population pressures due to the growing number of surviving inhabitants of those regions. The resources became scarce thus called for some of them to migrate to unconquered lands.   Smithsonian (2015), further explains that upright walking and tool making were closely linked with the drier habitats and the spread of grasslands. In this case, it is perceived that many vital human adaptations arose in the African savanna or were manipulated by environmental pressures of an expanding dry land (n.p).   A different outlook to explain the evolution of man would be not by habitat but by environmental instability. The environment varied but homo genus was not restricted to a specific kind of environment. Throughout the process of human evolution, human ancestors increased their ability to cope with different species as opposed to specializing on a specific habitat. Therefore, hominins managed to cope with environmental fluctuations by use of genetic adaptations, which involved several alleles or dissimilar types of genes available in the populace at diverse frequencies. While the environmental conditions change, the aspect of natural selection selected a single allele or genetic variant and left out the other. Genes present a range of diverse forms depending on the environments (phenotypic plasticity) thus help it to change to different environments (Smithsonian, 2015, n.p).  Moreover, hominins adapted through the development of structures and traits that would be used to cope in different environments. Smithsonian (2015), says that environmental changes to a specific direction would mean specialization to the specific conditions. If the environment got highly variable specifications for specific environments would have reduced advantages compared to structural make up and behaviors that that allow changing in random and unreliable conditions. Variability selection enabled hominins to develop advantageous variations and behavior that helped them to survive. Variability selection hypothesis therefore brings about the impression that human ancestors evolved overtime as a means to adjust to uncertainties in the environment (n.p). Hominins remains have been located in a variety of habitats such as wooded habitats and wooded grasslands, flood plains, gallery forest as well as dry bush lands. This indicates the ability of the genus homo to tolerate diverse environments. From as far as 1.9 million years back evidence of the genus homo can be located in several locations in Asia such as: Dmanisi, Yuanmou, Nihewan Basin, Java, (Smithsonian, 2015, n.p)  According to Larick and Ciochon (1996), dispersal of the genus homo to Asia, European and African regional distribution can not only be explained by the climatic changes only but also due to internal factors such as population saturation and advances in technology in the form of tool making and competition over natural resources. Factors that triggered the evolution of homo from Australopithecus also influenced its dispersal from Africa. These evidences would be viewed in terms of climatic, population pressures, morphological, technological, and behavioral. The striding gait, stone tools and scavenging served as the reason for the emergence of the genus homo. Increased population dominated the more temperate habitats under complex and less obvious conditions (n.p).

Early symbolic behavior, cultural adaptations and/or communal activities.

The modern man resorted to a number of symbolic behavior and cultural activities that did not characterize the earlier hominids. They exploited foodstuffs from natural resources leading to the development of agriculture dating to 12, 000 years ago. This further increased their population growth. A good example is the consumption of fish and shellfish, marine mammals and tortoises earlier than 40,000 years ago. Unlike the Neanderthals who were herbivores and upper Paleolithic was more varied in diet, which included aquatic components.  It is also worth noting that modern humans dedicated much of their time on creating and wearing ornaments, making cave and portable art and burying the dead. There arose evidences of mortuary practices and creation at points such as Lake Mungo in Australia (Stanford, Allen, & Antón, 2013, p. 344). Upper Paleolithic burial sites were characterized by burial pits and elaborate number of grave goods, multiple carefully arranged bodies. They also indicate that the dead were buried in decorated garments, cave arts and rock carvings also appear in Africa andAustralia. Statues, beads, and pendants are a characteristic associated with upper Paleolithic dating to 40,000years or later (Stanford, Allen, & Antón, 2013, p. 345).

Explanation for modern humans (Homo sapiens sapiens) being the only species of the genus Homo alive today.

The homo sapiens are the only surviving species of the genus homo today (Schmisek, 201, p. 102). Taxonomy differentiates homo sapiens from other species by physical characteristics, behavioral and social characteristics. Homo sapiens evolved from earlier homo sapiens showing skills with language and art as well as technological innovation. Schmisek (2013) further explains that Various homo species would have mastered the fire in the Paleolithic age. The genetic split between the predecessor of Neanderthals and homo sapiens would have occurred between four and seven hundred thousand years ago. (p. 104) DNA reveals that homo sapiens became a distinct species two hundred thousand years ago. This also reveals that modern humans also share a common ancestor referred as mitochondrial Eve or Africa eve. Homo sapiens then migrated from Africa and inhabited most part of the earth. Later 40,000 years ago, the modern human emerged. Neanderthals would have shared the earth with homo sapiens until about 28,000 years ago when they became extinct. After their extinction, the homo sapiens became the only surviving species of the genus homo. Homo sapiens sapiens developed agriculture, the skill of writing and forging bronze. From the analysis above other theories and myths of evolution stand challenged since they do not give as much evidence and prove as the evolution theory does. We realize how connected we are to other species of the genus homo. Yet the major distinguishing characteristic between man and the previous species is the size of the brain, bipedalism, smaller faces progressively smaller teeth, and jaws just as Brown, T. and Brown, K. (2007, p. 267)) states. The development of the modern man has caused man to explore and dominate the greater parts of the earth that were not previously occupied. However, this is not alien; the roots of exploration are drawn from our fore fathers.                                     References

Brown, T. A., & Brown, K. A. (2011). Bimolecular Archaeology: An Introduction. New York, NY: John Wiley & Sons.

Larick, R., & Ciochon, R. (1996). The African Emergence and Early Asian Dispersals of the Genus Homo. American Scientist. http://www.uiowa.edu/~bioanth/homo.html

Schmisek, B. (2013). Resurrection of the flesh, or, resurrection from the dead: Implications for theology. Collegeville, Minnesota: Liturgical Press.

Smithsonian National Museum of Natural History. 2015. What does it mean to be human? Climate effects on Human Evolution. http://humanorigins.si.edu/research/climate-research/effects

Stanford, C. B., Allen, J. S., & Antón, S. C. (2013). Exploring biological anthropology: The essentials. Boston: Pearson.

Stony Brook Human Evolution Symposium and Workshop, Grine, F. E., Fleagle, J. G., & Leakey, R. E. (2009). The first humans: Origin and early evolution of the genus Homo : contributions from the third Stony Brook Human Evolution Symposium and Workshop, October 3-October 7, 2006. Dordrecht: Springer. Human evolution http://humanorigins.si.edu/research/climate-research/effects 30/03/2015