Darwinism consists of the following claims:
- All living things are modified descendants of a common ancestor.
- Natural selection has been the principle mechanism of modification acting upon undirected variations that originate in DNA mutation.
- Unguided processes are sufficient to explain all features of living things - any appearance of design is simply an illusion.
Descent With Modification
- Main Article: Common descent
Descent with modification is the first element of Darwin's theory discussed in The Origin of Species. Darwin proposed that newer organisms are modified versions of their ancestors. Darwin theorized that all of the finches he observed on the Galapagos Islands had descended from one common ancestor, which had originated on the mainland of South America. Using that scenario as a model, he proposed that all living things are descendants of a single ancestral lifeform. Darwin used this theory to account for similarities between living organism and those in the fossil record.
Prentice Hall Biology (2008) describes the evolutionist interpretation as follows:
|“||Descent with modification also implies that all living organisms are related to one another. Look back in time, and you will find common ancestors shared by tigers, panthers, and cheetahs. Look farther back, and you will find ancestors that these felines share with horses, dogs, and bats. Farther back still are the common ancestors of mammals, birds, alligators, and fishes. If we look far enough back, the logic concludes, we could find the common ancestors of all living things. This is the principle known as common descent.||”|
- Main Article: Natural selection
Darwin's theory, which has become a tenet of evolutionary theory, states that the environment affects individual organisms in a population. Also known as "survival of the fittest", the theory basically describes organisms as in a continuous struggle with one another for food, shelter, and other necessities of life. The individual having the best characteristics for success in the struggle to survive will be more likely to reproduce and pass those characteristics on to the next generation.
- Main Article: Neo-darwinism
At the time Darwin wrote his manuscripts on evolution the scientific community knew nothing about genetics or how variation was created within a population. Gregor Mendel, the father of modern genetics, published his research several years after Darwin wrote The Origin of Species, which remain unrecognized for its significance until the early 1900s. As one of the fundamental principles of genetics, it was made clear that variety was limited to the genes present in the population, which were passed to offspring in predictable patterns. Mutations then were proposed as the source of variety driving evolution in population, leading to the perspective also known as the Modern Evolutionary Synthesis.
- Wells, Jonathan. The Politically Incorrect Guide to Darwinism and Intelligent Design, p.2, 2006. Regnery Publishing, Inc.
- Prentice Hall Biology. 2008. p382. Kenneth Miller & Joseph Levine.