Anthropology 103 Human Evolution

Anthropology 103 Human Evolution

Bonus

The chimps were feeding on a shrub known as Aspilia. The plant is believed to work as an antibiotic and could kill any disease-causing bacteria. It was believed to treat wounds and stomach ache among the chimpanzee community.

DNA

DNA is a biological molecule that stores all the genetic information of an organism. It contains coded information that defines an organism, and this information can be passed from parents to offspring during reproduction. The study of DNA is critical to determine processes that occurred during the evolution of human beings (Maslin, Shultz & Trauth, 2015). The detectable difference between human DNA and that of other primates is sufficient to give an estimate of how and when the two species branched apart during the evolutionary tree.

Alfred Wallace

Alfred Wallace is a naturalist who believed and came up with the theory of natural selection from which he believed all things, including humans, evolved. He believed that living things evolved from simple life forms over 3 billion years ago into complex beings, as seen in our world today. In his idea of natural selection, animals contain variations that result from differences in their gene pool as a result of mutations.  These traits can be passed on to offspring, and nature selects those that are fit to survive while the others die out. In the same case, humans evolved through natural selection with the fittest primates surviving while the unfit one died off.

Bottleneck

Bottleneck relates to a situation in which the population of a given species is significantly reduced to environmental changes such as floods, famine, fires, or human activities (Sonsthagen, Wilson & Underwood, 2017). For instance, the bottleneck was significant during the evolution of australopithecine into Homo erectus since it is believed that the latter population was able to walk the earth and breed, which reduced the Aistralopithecina population.

Biological Species Concept

It is a concept that defines species as organisms of a given population that can actually or potentially breed freely in nature and produce viable offspring without considering their similarities in terms of appearance. In this concept, it is believed that some organisms may look similar while they are different in the real sense (Maslin, Shultz & Trauth, 2015). During human evolution, this concept was important since it showed genetic continuity within the different species during the evolution as a result of the gene flow

Dental Formula

This is a formula that is used to demonstrate the different types of teeth that a mammal possesses. It is commonly written in four fractions where each fraction represents each type of tooth, and the upper and lower lines show the upper and lower jaws. The changes that occur within the jaw and dental morphology can be used as an important tool for studying human evolution (Maslin, Shultz & Trauth, 2015). The evolution of the jaw was believed is believed to have resulted in the unique formation of the human chin as well as contributed to the development of speech in humans as opposed to other primates.

Genetic Drift

Genetic drift is a phenomenon that results from a random sampling of organisms that causes a change or variations in the frequency of an existing gene/ allele within a given population. During human evolution, genetic drift caused an increase in the number of genetic differences between primates, which caused a bottleneck to primates, which had unfavorable alleles while the others survived and passed on the homozygous traits to their offspring (Sonsthagen, Wilson & Underwood, 2017). In this manner, human evolution occurred, and the more adapted human beings survived while the others died out, as seen in the human evolutionary tree.

Part Two Essay

What are the four forces evolution, and what are their relative roles? Which do you argue has the greatest impact on the evolution of a species or population?

Evolution is the process by which organisms gradually change in their genetic and phenotypic make-up.  The theories of evolution all have a supportive argument of a common origin due to the significant similarities of the genetic make-up in the form of DNA among different species of organisms (Maslin, Shultz & Trauth, 2015).  There are, however, four major forces that have determined and shaped the theories of evolution. These include the force of mutation, genetic drift, force of gene flow, and the force of natural selection. All these forces have various ways to explain the key steps resulting in the evolution of living things.

The Force of Mutation

Mutations come about as a result of differences in the genetic make-up of organisms. Mutations happen in the DNA, which codes for all the genetic information that makes up an organism.  The mutations occur in the chromosomes and genes, thereby contributing to physical and behavioral differences among species of the same kind. According to this force of evolution, since these mutations occur at the gene or chromosomal sections, then it becomes possible to pass down these mutated traits to the offspring during reproduction. This results in the emergence of a new species with different traits, unlike the parent, which is the basis of evolution.

The force of Gene flow

In this concept of evolution, it affects organisms that have a difference in their geographical location, which hinders the flow of genes among these species through mechanisms such as mating. This difference can cause the organisms to exhibit different genetic make-up based on their current occupation. The force, however, explains that this can be affected when these geographically separated organisms meet in the same geographical location (Saeb & Al-Naqeb, 2016). When such organisms exchange their genetic information through such processes such as mating, then the high biological diversity between the two species is reduced. It finally results in the evolution of species with lesser genetic variations and ones which are more alike.

Force of genetic drift

Genetic drift is defined as the phenomenon that results from a random sampling of organisms that causes a change or variations in the frequency of an existing gene/ allele within a given population. These changes have a significant effect on the smaller population as it is, in most cases, outlived (Saeb & Al-Naqeb, 2016). Genetic drift occurs when a small section of an entire population is separated from the rest due to factors such as drought, famine, floods, fires, or other natural calamities that species do not have direct control to. The smaller populations end up losing variations that are present in their gene frequencies.

Force of Natural Selection

In this concept, some organisms possess some advantageous survival traits over other organisms.  These organisms, therefore, have a greater chance of surviving in the natural environment and producing more offspring with favorable traits to enable them to continue surviving. These organisms are well adapted to the environment and are, therefore, able to able to survive in the prevailing environment as opposed to those with unfavorable traits (Saeb & Al-Naqeb, 2016). Nature, therefore, selects only the organisms that are fittest while those that weak die out and do not get a chance to reproduce. As such, a new species of more adapted organisms are produced.

The force of natural selection has the greatest impact on the evolution of organisms. It tries to incorporate the ideas of gene flow, mutations, and genetic drift through a natural mechanism in which other organisms do not have direct control to. It, in a clear manner, explains the happenings showing in evolution theories and how organisms develop from one form to the next and become more adapted even with the changes in their environment.

What is the relationship between humans and non-human primates? How did a primate legacy impact the human species biologically and behaviorally? What traits are common between other groups of primates and us, and which are unique to humans? Is there anything that makes us unique?

The human and non-human primates is an important topic of discussion in as much as anthropology is concerned. Evolution has shown the long term relationship between human beings and non-human primates. There are, however, not too many studies that have been conducted to explain the behavior and ecological patterns between human beings and non-human primates (Fuentes, 2006). However, due to the biological and behavioral overlaps, there remains to be a significant relationship between human beings and non-human primates.

Both the primates and non-human primates have a series of behavior common to both groups, such as possessing a large brain capacity. They are also characteristic of grasping hands, an extensive infant dependency, as well as an emphasis on visual signaling. They also exhibit a social complexity behavior that demonstrates the likeliness of the human and non-human primates to have a past connectedness as opposed to other mammals. The social interaction between human and non-human primates, such as baboons, has been shown to have a close relationship.

Human beings and the African apes have very close similarities that can be observed from body structure as well as the arrangement of their internal organs. There is a similarity index of about 96% between the DNA of human beings and that of chimpanzees.  These primates also have similar bone types, even though this may differ in size and shape as to those of human beings. The primates also demonstrate the presence of thumbs and hands (Fuentes, 2006). The thumb is separated from the other fingers, which enables them to easily grip substances. Despite these similarities, several factors differentiate human beings from other primates. Human beings have relatively shorter and weaker arms when compared to the legs as opposed to that of primates. Human feet also lack the capacity to grasp things, and this has seen human beings exhibit the behavior of bipedalism.

The human pelvis and spinal cord are more advanced, which gives human beings an erect posture, unlike the primates. The pelvis is shorter and broader, a feature that ensures human gain stability while they are walking. Human beings also have a small and more advanced brain capacity, which makes them more unique than other primates. The unique feature of the human body having numerous sweat glands as opposed to other primates that are covered by fur makes it easy to keep our bodies cool (Fuentes, 2006). Other primates have to depend on other mechanisms such as panting as a way of keeping their body cool.

It is, therefore, worth noting that there is a very close relationship between the human and non-human primates. There are, however, more research needs to be done to explain this evolutionary relationship and draw a clear picture when human beings branched from the primate family. More should also be done on the social behavior of these primates in their natural habitats to determine if they have any close relationship with those of human beings.

References

Fuentes, A. (2006). Human-nonhuman primate interconnections and their relevance to anthropology.

Saeb, A., & Al-Naqeb, D. (2016). The impact of evolutionary driving forces on human complex diseases: a population genetics approach. Scientifica, 2016.

Maslin, M. A., Shultz, S., & Trauth, M. H. (2015). A synthesis of the theories and concepts of early human evolution. Philosophical Transactions of the Royal Society B: Biological Sciences, 370(1663), 20140064.

Sonsthagen, S. A., Wilson, R. E., & Underwood, J. G. (2017). Genetic implications of bottleneck effects of differing severities on genetic diversity in naturally recovering populations: An example from Hawaiian coot and Hawaiian gallinule. Ecology and Evolution, 7(23), 9925-9934.