The acceptance of these ideas required an ideological revolution. Although I will be focusing on this last domain, for the sake of completeness I will put forth a short overview of his contributions—particularly as they inform his later ideas—to the first two areas.
A Secular View of Life Darwin founded a new branch of life science, evolutionary biology. Four of his contributions to evolutionary biology are especially important, as they held considerable sway beyond that discipline. The first is the nonconstancy of species, or the modern conception of evolution itself. The second is the notion of branching evolution, implying the common descent of all species of living things on earth from a single unique origin.
Darwin further noted that evolution must be gradual, with no major breaks or discontinuities. Finally, he reasoned that the mechanism of evolution was natural selection.
Despite the passing of a century before this new branch of philosophy fully developed, its eventual form is based on Darwinian concepts. For example, Darwin introduced historicity into science. Evolutionary biology, in contrast with physics and chemistry, is a historical science—the evolutionist attempts to explain events and processes that have already taken place.
Laws and experiments are inappropriate techniques for the explication of such events and processes. Instead one constructs a historical narrative, consisting of a tentative reconstruction of the particular scenario that led to the events one is trying to explain. For example, three different scenarios have been proposed for the sudden extinction of the dinosaurs at the end of the Cretaceous: a devastating epidemic; a catastrophic change of climate; and the impact of an asteroid, known as the Alvarez theory.
The first two narratives were ultimately refuted by evidence incompatible with them. All the known facts, however, fit the Alvarez theory, which is now widely accepted. The testing of historical narratives implies that the wide gap between science and the humanities that so troubled physicist C. Snow is actually nonexistent—by virtue of its methodology and its acceptance of the time factor that makes change possible, evolutionary biology serves as a bridge. The discovery of natural selection, by Darwin and Alfred Russel Wallace, must itself be counted as an extraordinary philosophical advance.
The principle remained unknown throughout the more than 2,year history of philosophy ranging from the Greeks to Hume, Kant and the Victorian era. The concept of natural selection had remarkable power for explaining directional and adaptive changes. Its nature is simplicity itself.
It is not a force like the forces described in the laws of physics; its mechanism is simply the elimination of inferior individuals. Those who survive. In fact, nothing is predetermined. Furthermore, the objective of selection even may change from one generation to the next, as environmental circumstances vary.
A diverse population is a necessity for the proper working of natural selection. Because of the importance of variation, natural selection should be considered a two-step process: the production of abundant variation is followed by the elimination of inferior individuals.
This latter step is directional. By adopting natural selection, Darwin settled the several-thousandyear- old argument among philosophers over chance or necessity. Change on the earth is the result of both, the first step being dominated by randomness, the second by necessity. Darwin was a holist: for him the object, or target, of selection was primarily the individual as a whole.
The geneticists, almost from on, in a rather reductionist spirit preferred to consider the gene the target of evolution. In the past 25 years, however, they have largely returned to the Darwinian view that the individual is the principal target.
For 80 years after , bitter controversy raged as to which of four competing evolutionary theories was valid. Lamarckian evolution relied on the inheritance of acquired characteristics.
Darwinism is now almost unanimously accepted by knowledgeable evolutionists. In addition, it has become the basic component of the new philosophy of biology. A most important principle of the new biological philosophy, undiscovered for almost a century after the publication of On the Origin of Species , is the dual nature of biological processes.
These activities are governed both by the universal laws of physics and chemistry and by a genetic program, itself the result of natural selection, which has molded the genotype for millions of generations. The causal factor of the possession of a genetic program is unique to living organisms, and it is totally absent in the inanimate world. Because of the backward state of molecular and genetic knowledge in his time, Darwin was unaware of this vital factor.
Another aspect of the new philosophy of biology concerns the role of laws. Laws give way to concepts in Darwinism. In the physical sciences, as a rule, theories are based on laws; for example, the laws of motion led to the theory of gravitation. In evolutionary biology, however, theories are largely based on concepts such as competition, female choice, selection, succession and dominance.
These biological concepts, and the theories based on them, cannot be reduced to the laws and theories of the physical sciences. Darwin himself never stated this idea plainly. During this period, a pronounced change in the methodology of biology took place. Would Charles like to go? Charles jumped at the opportunity. His father reluctantly gave permission, and the ship sailed from Plymouth on 27 December The main object was to make good naval charts of parts of South America, which was the speciality of Captain Fitzroy, who was also rather fundamentalist in his religious views.
It was while they were surveying the Galapagos Islands that Darwin made many observations which eventually led to his theory of evolution by natural selection, although he barely grasped the significance at the time. And so it was: the ten rocky islands were home to many plants and animals that were like those of neighbouring South America , but with distinct differences.
Half the species of birds living on these islands occurred nowhere else on the planet. Each island had its own species. How had this come about? Could this extraordinary variety really be explained by the idea that God had created all the species on Earth in six days? Could the variations he saw on the Galapagos have anything to do with the huge scale of geological time he had learnt about from geologists such as Sedgwick? In a tentative way, Darwin argued about these issues with Captain Fitzroy, whose dogmatic religious belief acted as a useful stimulant, though neither knew it at the time.
Darwin thought that the unique species of the Galapagos could not have been specially created for each island, but must have evolved from similar ancestors carried from the mainland and washed up on the islands.
These are said to be the necessary and sufficient conditions for natural selection to occur. Natural selection is the process in nature by which organisms better adapted to their environment tend to survive and reproduce more than those less adapted to their environment. For example, treefrogs are sometimes eaten by snakes and birds.
One example of recent natural selection in humans involves the ability to tolerate the sugar, lactose, in milk. In most parts of the world, adults are unable to drink milk because their body switches off the intestinal production of lactase, an enzyme that digests the sugar in the milk, after weaning. Genetic drift is a random process that can lead to large changes in populations over a short period of time. Charles Darwin is centrally important in the development of scientific and humanist ideas because he first made people aware of their place in the evolutionary process when the most powerful and intelligent form of life discovered how humanity had evolved.
Technology has advanced into many areas of our lives, making information more accessible, improving communication, changing transportation, and the list goes on. While it is easy to sit back and benefit from a plethora of technological advancements, it is crucial we do not become blind to its effects on society.
Science-related knowledge and scientific literacy provide essential tools for surviving in the news jungle and for responsible citizenship. They also teach us to understand our own actions, to review them critically, and to take care of our rights. This is why science education is important.
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Students work together to create innovative solutions to real-world problems and communicate their solutions with others. Begin typing your search term above and press enter to search. Press ESC to cancel. Ben Davis June 21, What was Charles Darwin main contribution to science?
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