Charles Darwin (1809-1888) is among the most influential historical figures and a naturalist whose theories have undoubtedly affected many generations. Darwin was born to Robert Waring Darwin, a physician, and Susannah Wedgewood in Shrewsbury, England. Darwin grew under the care of his father for the greater part of his life since his mother died when Darwin was eight years only. After studying in a local school in his elementary level, Darwin joined Edinburgh University for a degree in medicine which he dropped after two years of study.He then joined Cambridge University and pursued a degree in Theology and graduated in 1831.
Darwin’s interest in science rose at Cambridge University after spending time with John Henslow, a naturalist, who mentored Darwin and influenced him to collect specimens. He also read about the ideas of Adam Sedgwick, a geologist, thus influencing him to disagree with the idea of biological evolution. In 1831, Darwin got an opportunity to join a surveying expedition as an unpaid naturalist with the British Navy under Captain Robert Fitz-Roy (Greenberger, 2005).The five year expedition around the world especially in the Galapagos Islands, South America, formed a foundation for Darwin’s work on natural selection and eventually the theory of evolution. The voyage The Galapagos Islands have organisms that are distinct from other organisms in the world. During Darwin’s voyage to the Islands, he was able to identify that the there were differences between finches in the different islands especially as regards to the shape and size of the beaks.
Notable was the shape and size of the beak differed depending on the diet of each particular bird thus concluding that the finches that originated from South America before the formation of the Galapagos Islands adapted to different diets in the different islands. This was a means of ensuring survival and reproduction and is currently referred to as adaptive radiation. Darwin was able to substantiate that finches whose beaks would enable feeding on cactus were able to obtain more food in the arid environments and thus their chances of reproduction and survival was higher.This phenomenon was observed in the different environments and thus nature had a way of selecting the most suitable species in survival and reproduction eventually birthing the ‘natural selection’ process (O’Neill, 2010). Natural selection is central to evolution An important aspect of natural selection as a process of evolution as per Darwin was that species (finches in this case) had an innate variation and nature’s role was to select the most suitable variation that would ensure survival and reproduction.This therefore negated Lamarck’s view that the environment was responsible for altering specific traits in species and the altered species were inheritable.
The natural selection process according to Darwin’s view was that only the fittest species in any given population had greater chances of surviving to reproduce and consequently pass down the fit traits to following generation. Apparently, the “survival of the fittest” notion was established upon Thomas Malthus work that human populations had the capacity to increase exponentially unless food limitation checks the population (O’Neill, 2010).Likewise, Darwin concluded that diseases, predators and inadequate food acted as checks for a possible rapid increase in population size for any organism. One of Darwin’s supportive evidence of natural selection as a process of evolution has been observed in moths that live in industrial cities in England.
Soot from the industries in the 19th century darkened buildings thus brightly colored moths were easily identified by bird predators whereas dark colored moths survived predation. Resultantly, the population of the dark colored moths sprouted reaching to about 85 percent compared to bright moths.As from mid-20th century however, the initially darkened buildings and trees became brighter as pollution was controlled and the buildings were refurbished. As a result, the brightly colored moths were better suited to evade predators as opposed to the dark colored ones. Currently, the population of the bright moths has risen significantly due to better camouflage. One of the central views that Darwin had about natural selection as an evolution process is that luck is an important aspect of evolution.
This therefore followed that a population that was not favored to have traits that allowed survival and reproduction were deemed to become extinct due to inability to be accustomed to a constantly changing environment. The evolution theory It is pertinent to note that much of Darwin’s work on natural selection and evolution was after the voyage and that it was based on his experiences during the expedition (O’Neill, 2010). His first work on evolution was recorded in a notebook in 1837 and the notebook was essential for keeping record of important ideas and facts that would support the upcoming theory of evolution.Initial supportive information on evolution was based on findings that there was resemblance between fossils that belonged to same relative ages compared to fossils whose relative ages were widely different. The existent of vestigial organs as well as the embryological development of organisms reinforced his views of evolution as a real process. In 1842, he had prepared a 35 page abstract on the theory of evolution.
In 1844, Darwin, with the assistance of his wife Emma expanded the manuscript to 230 pages but still kept the manuscript a secret which was supposed to be published in occasion of his death (Age of the Sage, 2010).Darwin was preparing the evolution manuscripts in secret in fear of facing stern opposition from the church. This was in realization that his ideas on evolution were contrary to religious teachings on creation. Darwin was compelled to publicize his theory on evolution in 1858 after another naturalist, Alfred Russel Wallace, presented an essay on coincidentally similar evolution and natural selection views. Having realized that Wallace’s views would overtake his, Darwin agreed to joint airing of his work with that of Wallace in scientific circles.
The following year, 1859, Darwin published his remarkable and controversial 490 page work, The Origin of Species. In The Origin of Species, one aspect of the theory of evolution is stated as follows: As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequently recurring struggle for existence, it follows that any being, if it varies, however slightly in any manner profitable to itself, under the complex and sometimes varying conditions of life, will have a better chance of surviving, and thus be naturally selected.From the strong principle of inheritance, any selected variety will tend to propagate its new and modified form (The Age of the Sage, 2010, para 19). The basic principles of Darwin’s theory of evolution are captured in the above quotation with the aspect of natural selection emerging as the central idea of evolution.
The theory of evolution also upheld that “life forms do change through time” (O’Neill, 2010, para 13) thus repositioning the view that human species was about 6000 years old. In the theory of evolution, it is accepted that evolution is a process that takes place slowly over millions of years.On another note, organisms have physical variations and that nature is responsible for selecting the most suitable traits that fits the environment for survival and reproduction. This is the concept of natural selection and a striking evidence of the existence of evolution.
Darwin realized that the process of natural selection was a slow and gradual one. In explaining the variations found in a population, Darwin maintained that the small differences between offspring and parents were random and had potential to convey certain advantages to the organism.Advantages such as being healthier or being able to camouflage from predators increase chances of survival for that organism. Survival further transmits the benefit of breeding thus the favorable traits are passed to the next generation.
This spread of a survival advantage extends over generations with minor and accumulating changes occurring up to a point where a new species is likely to emerge (Masci, 2009). This was also a supportive fact that human beings must have been older than 6,000 years and that evolution actually took place.The idea of all living organisms having a common ancestor is also articulated in the theory of evolution. In explaining the origin of living organisms, Darwin’s theory of evolution considers that early cells went through the process of evolution with millions of species emanating from the cells. Viewed through a modern explanation, the evolution process involved mutation whereby mutation led to better adaptation or risked the organism from being eliminated in the environment via natural selection.
Accumulated mutations (defined as subtle changes by Darwin) over generations led to development of new species that are different from the parent organisms. An example and evidence of the above described form of evolution has been observed in development of antibiotic resistance in bacteria. As earlier stated, Darwin also strengthened his theory of evolution by making a comparison of homologous structures which further supports the idea of a common ancestor. Existence off vestigial structures in organisms was also cited as evidence that change has been occurring in organisms over time thus reinforcing the evidence of evolution.The embryological development evidence cites that since there exists a similarity in embryos of virtually all organisms (birds, fish, reptiles and mammals), all these organisms must have had a common ancestor, though a distance one (Baig, 2000). Controversy and opposition towards Darwin’s theory Whereas Darwin’s theory of evolution gained much acceptance among scientists by convincing the scientists of existence of evolution via natural selection, the theory was and still is controversial.
The strongest opposition came from religious groups, more so Christianity which was strongly established in England. The theory of evolution threatened the Christian belief in God as the Creator of all things and that since creation; all living organisms have remained unchanged biologically. The theory was contradicting with Christian faith in stating that there must have been life more than 6,000 years ago and thus it was not greatly accepted among Christians.It should however be notable that archeological evidence has been presented to indicate that life must have existed prior to 6,000 years ago.
One archeologist, Boucher de Perthes, presented prehistoric tools and bones which were later confirmed to have belonged to the last ice age period (O’Neill, 2010). It should be noted that the idea of “special creationism” (species were created and remained unchanged) was not only upheld by Christians but it was also popular among early scientists.Darwin’s theory of evolution was therefore a total shake up in the field of science and religion. The great opposition of the theory coming from Christians was also due to the fact that the theory of evolution was relocating man from his ‘special position’ as per God’s creation by claiming that there exists a common ancestor for all organisms.
Much of the opposition over Darwin’s theory was in Britain with church leaders hotly debating and opposing the theory that seemed to challenge their long-held faith.The Catholics and the Anglican churches were particularly reluctant to accept Darwin’s view and this extended through the early 20th century. Whereas the debate on the theory of evolution still reigns especially with the advancement of science and technology, most churches come to the agreement that evolution actually existed but still maintained that it occurred at God’s direction (AllAboutScience, 2010). While science has increasingly supported the theory of evolution, certain scientists have also gone ahead to disapprove the theory.
Molecular biologists and geneticists for instance have challenged Darwin’s view that there exists no complex organ (or an irreducibly complex system) by highlighting bacterial cells of being made of complex molecular machinery despite being viewed as among the smallest and microorganisms. In view of advancements in science and technology, some scientists have cited the theory as being in crisis (AllAboutScience, 2010). Darwin did not stop researching and writing on evolution after publishing The Origin of Species. Instead, he sought to advance the theory of evolution by publishing other works variation and selection.Among his other popular publications include “The Variation of Animals and Plants under Domestication and The Descent of Man, and Selection in Relation to Sex” (Boeree, 2000, para 16).
Darwin also explored the evolution of emotions thus laying the ground for sociobiology. By the time he died in 1882, Darwin had left a mark in the field of biology and an even greater mark in the entire fields of science and religion. These impacts are felt presently through the continued debate on evolution, especially the origin of man. ConclusionCharles Darwin emerges as a true naturalist who presented the idea of evolution in a clear and understandable manner. The theory of evolution through natural selection would not have occurred to Darwin had he not abandoned a career in medicine and later joining the British Navy expedition.
Indeed, his observations on the finches of Galapagos Islands are a strong foundation that natural selection favors the fittest individual. Despite fearing a backlash from the strong religious structures in Britain, Darwin was daring enough to pursue his thoughts and perspectives on evolution.Indeed, his publication on The Origin of Species portrays all organisms as having a common ancestor. In addition, all organisms have variations and these variations confer advantages that ensure survival and reproduction. Consequently, only the fittest organism survives to pass the ‘fit’ traits to the next generation and eventually a new species may emerge.
These are views that were not taken lightly by those who held unto the idea of special creationism. Whereas, controversies have continued to reign regarding the evolution theory, evidence has been increasing supporting Darwin’s views on evolution.
