Evolution refers to the process by which living organisms gradually change from simple life forms to more complex ones over a long period of time. Studying evolution is crucial since it helps humans to comprehend their life history. Therefore, it is important to understand evolution because it is a focal point for scientific investigation into the nature and origin of life. It also offers scientific explanations for the great diversity of organisms and their similarities in structure and function. The concept of evolution as presented by Charles Darwin has numerous scientific evidence as well as its applications worldwide. The process of evolution through natural selection as asserted by Charles Darwin is indisputable because of the shared characteristics among species, continuous progressions in species, as well as similarities in traits between species and the remnants of their past generation.
Summary of Source Material
The documentary What Darwin Never Knew by Nova is anchored on Darwin’s book The Origin of Species, where Charles Darwin proposes an explanation for the mechanisms of evolution. The main idea of the documentary is that Darwin put forward his explanation based on a concept he called natural selection. He observed that variations occurred within members of a population. These variations arise by chance and from within the individual. Through sexual reproduction, these characteristics are transmitted to successful offspring. Some of the variations confer an advantage to the individuals while others are disadvantageous. Recently, scientists have put forward the case of the peppered moth Biston betularia as an example of natural selection leading to speciation. This moth is found in Britain. Its common type is speckled white form while the other one is black melanic form. Before the industrial revolution, the form was well camouflaged against tree trunks with similar pattern and colorization. During the industrial revolution, the environment was darkened by soot. Due to this change, the dark form blended well against the bark trees, which had been darkened by soot and smoke. These dark forms were better protected in the industrial area against predation from birds than the lighter forms. In the smoke and soot-polluted areas, there is a high frequency of this melanic form while in the soot-free areas, the speckled white moths predominate. Thus, the agent of natural selection was selective predation on the unprotected forms. The occurrence of the melanic form could have been due to mutation. This case may well represent a possible transition towards speciation, but, now, varieties represent polymorphic forms within a species.
Focus and Support (Arguments for Evolution)
In line with the documentary, one of the key arguments for evolution is that species across the world share similar characteristics that are reflective of a common ancestry. The process of evolution stands since the closest relatives such as man and animals such as apes share similar characteristics such as bipedalism. It proves that they have originated from a common ancestor hence supporting the whole theory postulated by Charles Darwin. The patterning of similar characteristics is widespread across the world, and it continues to replicate across all species of the world, making the theory acceptable. The process of evolution is valid from this view since these shared similarities were inherited from a common ancestor among the species. Species that have more similarities tend to live near each other because of the similar adaptability patterns. A perfect example is the penguin species that only live in the Southern Hemisphere while marsupials inhabit Australia exclusively. Thus, if the process of evolution were false, then such geographic patterning would be senseless.
Another relevant argument in support of evolution is that there are continuous progressions of species changing over the years. Darwin’s theory of evolution is realistic as evidenced by the extinct life forms of animals found as fossils. The extinct species such as dinosaurs have drastically different structures or body orientations from the present generations of the same species. Other examples that highlight the changes include giant sloths and baculites. For human beings, lineages have also changed overtime with the transformation in the kind of lifestyle and technological utilization resulting in the improvement of lifestyles, hence underscoring the reality of the whole process of evolution. As much as similar characteristics are shared among species, there have been continued transformations in the kinds of lifestyles, relationships, and even the body structure that show the contribution of evolution to the world. The geographic distribution of species through the present artificial selection performed by human beings is a reflection of the process of evolution that has been and is continuously taking place.
The third notable argument in support of evolution is that species in the world exhibit traits that are the remnants of their past generations. Species have marks of their past generations that reflect their relationships and associations with each other. The signs of origin emanate from the traits that are important for the adaptation and survival of different species. The absence of these traits would have made it difficult to appreciate the existence of the process of evolution and its contribution to different living organisms. For instance, in the study of animals such as snakes and whales, Darwin recognized the view that they tend to develop limbs that disappear before they are born, which essential for their adaptability purposes.
However, despite various scientific evidence that support Charles Darwin’s theory of evolution, it has faced numerous oppositions from natural ethnologists and scientists. Natural ethnologists believe in the existence of harmony and perfection. There are other arguments such as that the struggle for existence can only occur on small scales geographically. With the fluctuation of climate, the idea of an exponential increase in populations is realized. Hence, there is an enormous increase in the distribution, and the struggle for existence is either done away with or relaxed. In addition, most scientists in the United States discourage the use of the struggle for existence in explaining Charles Darwin’s ideas. They invented an idea referred to as cooperation for mutual benefit. Scientists from the Chicago school studied ecology during the 20th century, and they put much effort in studying cooperation and competition that occurs between organisms. They discovered that competition could be linked to both cooperative as well as an inoperative force in a population. They concluded that cooperation and the struggle for existence were vital in driving the process of evolution. Therefore, they added cooperation as a complexity to the concept of the struggle for existence. For instance, it was alluded that the struggle for existence was more at an individual level. As far as it was concerned, the cooperation was viewed to be crucial as it led to increased homeostatic control. Homeostasis was a phenomenon that was of interest, as competition at an individual level could have resulted to group homeostasis.
The documentary reveals the view that, according to Charles Darwin, natural selection is a chance occurrence because neither the individual nor the environment controls the direction of change. Those individuals that are selected for reproduction thus transmit the variations to their offspring. The gradual accumulation of small variations from generation to generation over a long period of time leads to the emergence of new forms of species. The variations that Darwin regarded as raw materials for the evolution process have now been traced to changes that occur at the level of the gene or the chromosomes. These changes are called mutations. Therefore, the evolution process by Charles Darwin is vital and supported by scientific evidence, as well as its application in natural selection through the shared characteristics, continued progression of species, and shared traits with the remnants of ancestors.