Evolution
Outline Introduction Darwin’s Formative Years Darwin Discovers Evolution Writing the Origin The Impact of the Origin Sexual Selection The Reaction to the Descent Conclusion Introduction It is commonly thought today that the theory of evolution originated from Darwin in the nineteenth century. ... Therefore, by Darwins time the idea that species change from one type into another was by no means new, but was rejected by most because the proponents of evolution could not come up with a satisfactory mechanism that would explain this change. ... However, these theories of evolution were based on explanations that offered no demonstrated mechanism. Darwins theory of evolution differs in that it is based on three easily verified observations. ... Darwin than proceeded to elaborate on the mechanism of evolution by suggesting that in the universal struggle for life, nature selects those individuals who are best suited (fittest) for the struggle, and these individuals in turn reproduce more than those who are less fit, thus changing the composition of the population. ... Therefore, it was Darwin who made the theory of evolution feasible by providing the mechanisms of natural and sexual selection. ... Nevertheless, Erasamus may have unconsciously influenced Darwin in preparing the way for evolution by natural selection. ... It is commonly thought that Darwin used the voyage to test his theory of evolution, but this is highly unlikely. ... Darwin Discovers Evolution. It appears to be that only sometime in 1837 did Darwin first start to entertain the idea of evolution seriously. ... Curiously, Darwin asserts that in originating his theory of evolution he was trying to follow Baconian principles, that is collect facts before theorizing. ... However, as his notebooks of the time amply demonstrate, he was speculating boldly from the very beginning in favor of evolution. ... Darwin Discovers Natural Selection During his early theorizing Darwin was fixated upon the whys of evolution. ... It seems that apart from the occasional reference to adaptation, Darwin ,at that time, almost deliberately tried to avoid the contemporary theories of the mechanics of evolution. Notwithstanding, Darwin, sooner or later, had to confront the question of how evolution occurred. ... By this chance encounter than, Darwins theory was provided with a rationale, and the how of evolution came to supplement the why. ... However, Darwin still proceeded to write his ideas on evolution at a leisurely pace, and not until 1856, when urged by his colleague Lyell, did he start working on his magnum opus, the Origin. ... There was an understanding on the part of religion that evolution was discredited by science. ... For Darwin sexual selection was not simply a subcategory of natural selection, but rather an alternative or complementary mechanism of evolution. ... It is therefore inaccurate, from this point on, to refer to Darwins theory as simply evolution by natural selection (Darwin himself called the theory the principle of evolution). The primary reason why Darwin abandoned natural selection in favor of sexual selection was the fact that natural selection could not properly explain either the evolution of man from the animals or the differences between the sexes and races. ... For instance, Hooker, who at that time found evolution discussed everywhere relates the following: I dined out three times last weak, and at every table heard evolution talked of as an accepted fact, and the descent of man with calmness. ... Not only did his theory of evolution illuminate our past, but also the present and the future were now possible to interpret in Darwinian terms. Probably more so than any other scientific theory, Darwins theory of evolution, lends itself to various social interpretations known as social Darwinism.