What Are the Defining Features of a Scientific Argument and How Are They Dependent on a Historical Content?

What are the defining features of a scientific argument and how are they dependent on a historical content?

In order to answer this question I will concentrate on the scientific argument for natural selection in Charles Darwin's book, The Origin of Species. I will structure my essay in such a way that I will give a brief background of the important features of Charles Darwin's life and the influences leading up to his writing off The Origin of Species, I will then specify a defining feature of Darwin's argument for natural selection and explain the historical views and influences surrounding that specific point and the effects they may have had on Darwin's work, I will then do the same with the next point following the order of the argument as put forward by Darwin.

Darwin was born in 1809 in Shrewsbury to an Anglican family; he first studied medicine at Edinburgh University, a subject the he found himself to have no interest in. Darwin found more interest in working in the university museum helping with classification and learning bird preservation. More over he helped Robert Grant; another member of the Edinburgh University, in studying marine invertebrates, Robert Grant was the first person to introduce him to the idea transmutation in animals when praising the theory of Lamarckism. Unhappy with his son's lack of interest in his studies Darwin's father sent him to Cambridge University to become an Anglican Pastor. It was at Cambridge where he first began work in taxonomy with a collection of beetles. In terms of theories of nature Darwin was often shown the religious view that there was a divine design in nature and that god acts through laws of nature from the study of William Paley and Cuvier. However he would also have been exposed to the works of Herschel, a man who promoted inductive reasoning through observation. Darwin took these influences with him after his time at Cambridge where he was asked by Robert Fitzroy to join on a two year voyage around the coast of South America as a collector of data of natural phenomena on the HMS Beagle. It was many years after his voyage that he published his scientific argument of evolution in his book, On the Origin of Species.

The first defining feature of Darwin's argument is one that was heavily influenced by Thomas Malthus's essay on the principle of population. The idea that, animals across all species produce enough offspring that the population of the species should grow, however, despite fluctuations, most populations stay roughly the same in a stable environment where food and resources are limited but constant. Darwin infers from this that, with an engorged population and limited resources there must be a struggle for survival in which animals compete for these resources, some surviving and others not, accounting for the constant population size. Many people believe that Darwin took this idea from Malthus's Iron law that essentially stated, in affluent societies a growing population will eventually lead to vital resources being over stretched, inevitably from this, a certain percentage of the population is relegated to poverty. Malthus proposed positive and preventative checks that allow resources to remain amicable, positive checks being raising death rate through war, disease and hunger and preventative checks coming in the form of birth control, abortion and celibacy. The equivalent in the animal kingdom, as Darwin saw it, was that the animals that could not fight for resources and where relegated the equivalent of poverty would not survive long enough to pass on their genes.

The second major feature of Darwin's scientific argument is that, in these populations where animals have to struggle to survive, there are individuals in the population that have variations that make them better suited to their environment, and so these individuals are better suited to retaining the needed resources to survive longer. Darwin first made this observation whilst on the second voyage of the HMS Beagle. When in the Galapagos Islands he came across finches that he had not observed before, theses finches had a distinct beak better suited to catching insects on the island of Galapagos. Darwin preserved these finches and took them back to England, along with other sets of birds he had retrieved in the Chatham and Charles Islands. On his return he showed the birds to ornithologist, John Gould, for identification. Gould concluded that the finches where to dissimilar from the other birds and finches that had been observed before that they were had to be considered as an entirely new group. Moreover, Darwin had witnessed, while with his co worker and companion Joseph Hooker in their eight year study of barnacles, that through his taxonomy of the creatures he identified that there were different variations of barnacles depending their particular environment, however the barnacles all shared the same basic features that made them recognizable as barnacles. From this Darwin concluded that some individuals types of animals appeared to have developed featured that better suited them to their environment despite sharing similar characteristics to the general population.

The third key feature of Darwin's Argument that he infers from the second, is the idea that those animals who have features better suited to the environment are more likely to live longer to the point where they can pass on there genes, where as the animals that do not have that feature will not survive long enough to reach the reproductive stage. These weaker animals that are not suited to the environment die out and so do their genes, therefore the advantageous gene will become more prominent in the species. Darwin is likely to have taken influence for his idea of evolution from Jean-Baptiste Lamarck and his idea of transmutation from the theory of Lamarckism. Lamarckism was the first theory that brought evolution firmly into public thought as one of the most widely read books in the nineteenth century. Lamarck's work and his book Philosophie Zoologique was something Darwin would have read and studied in his time