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The History of the Concept of Natural Selection

发布时间:2018-02-14
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INTRODUCTION

Charles Darwin was born in the year 1809 on 12th February in Britain . His interest was to be a priest but his father Robert Darwin wanted him to study medicine, on the course of doing that,he discovered that he had a phobia for blood and as result he decided to go into study of nature and geology. He became an English naturalist and geologist and was best known for his evolutionary theory. He died in April 19th 1882Evolution is the change in the inherited characteristics of biological population over successive generation it can also be defined as the series of gradual changes of living things over a long period of time depending on the condition at that point in time. In science, useful discoveries and theories may be carried out independently by researchers from similar or different perspectives. The most popular theory of evolution is the one of Charles Darwin(1809 ­ 1882)he was one of the most recognized scientist in the world because of his theory on evolution;the origin of species by the means of natural selection in the year 1859.this theory had created a diverse effect on philosophy,science,religion and also on politics.

The theory of Charles Darwin began its way after he completed his famous journey. He spent 21years (1838­1859) in England to organize and to complete his work. In the process of doing that he received a manuscript telling him that a naturalist Alfred Russell Wallace is already working on the same idea as his. According to Arthur Kieth,Wallace traveled and studied in the amazon and the south pacific as Darwin did many years ago and he followed completely and independently the line of reasoning as Darwin to make complete sense out of the data he collated. He titled his own discoveries as Wallace's manuscript on the biological operation of natural selection in the origin of new species. Wallace mailed his discoveries to Darwin and for commendation. This prompted Darwin to publish his work and surprisingly all 1250 c0pies were sold out the same day. Wallace made many other contributions to science and he is recognized by biologists as a prominent naturalist. However ,it is Darwin who is remembered for this great biological discovery.

THE THOERY OF BIOLOGICAL EVOLUTION BY THE MEANS OF

NATURAL SELECTION

The Darwin theory began as a journey on the HMS Beagle(1831­ 1836) in the English government's circling expenditure to map out the shape of the continents and to study and collated different species of plant and animals. Charles Darwin was the naturalist on this ship and he made a lot of observation on climate and weather patterns,geological formation,fossils,plant and animal. He collected and strictly studied a large number of specimen.

In his study,he observed that some animals are similar in so many ways but vary in some aspects in different islands as an ability to adapt to the environment and continuity of that specie. This observation of viability within species became a major concept in his later work on natural selection. He also observed that fossils of supposedly extinct species of these islands are similar and they resemble living species of the same geographical region. This brought him to the aspect of evolution which made him understand that preexisting organisms change gradually as time passes by.

It is interesting how both Wallace and Darwin's naturalistic ideas had the same concept with each other and how their work had been influenced by Thomas R. Malthus an economist who had published an essay on the principle of population in1798.in his essay, he suggested that “the power of is in definitely greater than the power of the earth to produce sustenance for man”. He also formulated that human condition will worsen with the rate at which population increases and will give rise to rivalry,competition,misery and predation as a struggle to for their satisfaction of increasingly scarce goods. According to Malthus,this increasingly scarce goods will be checked by natural and artificial disasters like drought,famine,warfare ,diseases e.t.c. As will notice, the Darwinian concept of natural selection and the Malthusian theories of population are similar.

Darwin sees his theory of biological evolution by the means of natural selection as the following;

  1. life is a process of natural selection
  2. life is a struggle for survival
  3. living things compete for space food and mate
  4. some living things have features of characteristics that help them survive
  5. while trying to survive conditions of the earth change

EXPLANATION OF CHARLES DARWINS' THEORIES BY THE MEANS OF

NATURAL SELECTION

1)Life is a process of natural selection:natural selection is a natural process by which organisms posses certain heritable characteristics that render them more capable of surviving in a certain environment, to reproduce,multiply in population and to ensure continuity of that trait. Since the less privileged fail to adapt to the environment,they die or go extinct. There are three types of natural selection as follows;

a)directional selection:this is where there is one extreme value selected for a change in one direction. It always occurs with the change in allele frequency because the allele frequency has to increase . Example of this kind of selection is speed. That is,ability of being fast in growth,reproduction,movement etc.

b) Disruptive selection:this is where the extremes which are both selected for the observation in nature which has the opposite effect of stabilizing selections. It eliminates the phenotype near the average value and thus,favor it thereby,the resulting circumstances is that the disruptive selection tends to maintain the amount of genetic variation within the population. Example of this is the predator ­ prey relationship. Predators have mark a certain feature on the prey and as a re ult, they move away or go extent to find a safe habitation so will the predators for the purpose of hunting for food so also happens in plants.

c)Stabilizing selection:this where the extremes are selected against where the selections are greatly reduced on one extreme in the range of the phenotype and this would result to a directional change in the average characteristics of the particular population. For example height or size. Most selections are made not on extremely fat or tall nor extremely short but on average height or size.

c)Life is a struggle for survival:organisms day by day to meet up their needs which in process, causes a form of struggle towards achieving that. This brings us to the term 'survival of the fittest' which means the process of struggling to meet up with needs marks the process of needing to survive. The weak ones in this case tend to get eliminated either through killing ,die of starvation or they go extinct leaving the stronger ones to survive and to continue life in that form. Note that any form of act taken by an organism or man is in order to survive. According to Darwin, a struggle for survival produces new genetic materials for new and better species to evolve and that it (struggle for survival) only decrease specie variety not increase it.

  1. Living things compete for space food and mate;this theory is directly linked to the above because struggle in this context means competition. The Malthusian theory has already told us that nature does not and cannot provide enough resources for the organisms on earth. hat is,resources are always limited because rate at which population increases is at geometrical rate and food production is at arithmetic rate. This makes the environment hostile and highly competitive in order to attain the best of this limited resources causing a distinctive classification of organisms that is,prey and predators. A prey is any animal that can be considered a form of food to to another and predator is it which preys on eatable animals. The predators seem to be selected by nature to be the strongest in this environment and tend to have to eliminate the less privileged ones thereby, depriving them of food and space. Competition also competition occurs within a specie for food or getting the best mate. Therefore, competition is a major sector of life and without competition, life will loose its value.
  1. Some living things have features or characteristics to help them survive;organisms posses some certain trait of characteristics to enable them protect themselves against predators or as power to do satisfy its need and to avoid being eliminated. This applies to both plants and animal. Example of these is; for plants poison ivy which excretes some kind of oil on the surface of its leaves and who eve touches it gets a terrible rash. Another example of plants are insectivorous plants that gives out a nice scent to attract insect and to use them as food when they come closer. The one of animals is for example porcupine which erects its thorns to scare away its predators.
  1. While trying to survive condition of the earth change;in the process of searching for or when running away from predation,disease or some natural disasters will occur I.e, drought,famine and war. This occurs predation rate accelerates and the population of preys reduces greatly. Unlimited food causes the class of the predators to engage in war as a form of competition thereby killing one another and when this preys go extinct or die the predators suffer extreme hunger and cause famine. They end up surviving one water alone and some water organisms. As they continue depending on water alone it gets reduced and leads to the elimination of some on the fit and then the water finally finishes hence they need to find another new habitat that can support their existence.

From the theories above we can deduct that these theories depend on each other and with all of them working together,explain life completely. In as much as this book was the best seller at that time and was believed by many,it also went through some criticism and caused some kind of violence between humans. Many religions didn't agree on Darwin theory on origin of man ,many religion believe that man was created by a Divine creature and they feel insulted when Charles Darwin said origin of life is from fish in the water it even got to the length of banning schools from teaching evolution but the name was changed to a new subject called intelligent design and today, Darwinism is being taught world wide.

So also his theory made man to think that human are created in races that is,the stronger ones are allowed to prey on the less powerful and they can erase them and collect their wealth and properties. In one of his publications he advocated a “race war among human beings believing that this world would produce better result if one of the races of mankind will be terminated” and “during the struggle for survival,the preys should be beaten out during the course of further modification”. This statement was what led to the formation of world war I(1914­ 1918) where the Nazi-st dictator Adolf Hitler used eugenic arguments to convince youths that they were the master race and also convinced them to engage in war to invade locations containing less privileged population. Races like the gypsies and the Jews were greatly affected by this evasion.

IMPACT OF DARWINS' THOERY ON THE SOCIETY

Even though the theory of Charles Darwin had some negative effects on the human lives,it made great impact on some people's lives and work as follows.

Social Darwinism has greatly influenced the work of the great Andrew Carnegie and john D. Rockefeller who were the 19th century industrialists. They believe that competition is a good characteristics of a good business .they said though this competition will cause grief to some people,it is important for the whole market to ensure survival of the fittest. Millionaires in this case are the superior men who have gone through diverse number of struggle to achieve that height.

It also had impact on the work of Herbert Spencer a social biologist who formulated the phrase “the survival of the fittest”which was later used by Darwin in his theory. He believes that all theories of Charles Darwin applies to every aspect of human interaction and act and he argued that government should not interfere in any form of human competition by trying to regulate economy or poverty. He belies that if any instability occurs in the economy or the peoples standard of living,it should be left along because it will adjust itself naturally. This lead to the laissez­faire political and economical system that favors the selfish interest in social and business affairs. in this case poor and less individuals are left to die of join the competing race.

Darwin's theory also had and still has impact on science on the fields of biology,psychology,anthropology and sociology. It created a new interest in the study and discoveries on fossils and research on archaeology and paleontology. It also made scientist have interest I n the study of genetics and helping Mendel in his work to prominence by the end of 18th century. He was the first scientist to invent the study on genetics and his work was published in early 19th century. He found out that minor changes observed by Darwin were as a result of presence of recessive genes controlling human behavior and could not result to formation of new species but along the line, a scientist Hugo DE Vries recognized Mendel's work and created his own postulate on mutation. Using different plant he experimented on ,he successfully produced new plants forms over years.

In conclusion,Charles Darwin, his theories and his books have created a great in pact universally even though it went through so many criticism and had caused so many negative impact on the lives of humans,Darwinism has exceeded the point of being about a naturalist but has even become an idea or a concept.

REFFERENCIES

1)WWW.prenhall.com/freeman/biology

2)www.brookerbiology,com

3)www.squ.edu.om/med­lib

4)www.the darwinpapers.com/oldsite

5)www.umich.edu/~phyl/anthro/natsel

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