Creation vs. Evolution

Neo-Darwinism

As you would expect with a field of scientific inquiry, much has been discovered since the time of Darwin. In particular, current knowledge of genetics has been applied to evolution. Consequently, the theory of evolution has been modified and augmented. These new changes are referred to as Neo-Darwinism. An even newer term that supercedes Neo-Darwinism has been coined by Futuyma to cover the current ideas on evolution -- Modern Synthesis. Following is a description of Modern Synthesis.

The major tenets of the evolutionary synthesis, then, were that populations contain genetic variation that arises by random (i.e. not adaptively directed) mutation and recombination; that populations evolve by changes in gene frequency brought about by random genetic drift, gene flow, and especially natural selection; that most adaptive genetic variants have individually slight phenotypic effects so that phenotypic changes are gradual (although some alleles with discrete effects may be advantageous, as in certain color polymorphisms); that diversification comes about by speculation, which normally entails the gradual evolution of reproductive isolation among populations; and that these processes, continued for sufficiently long, give rise to changes of such great magnitude as to warrant the designation of higher taxonomic levels (genera, families, and so forth)."
- Futuyma, D.J. in Evolutionary Biology, Sinauer Associates, 1986; p.12

For a fuller explanation of Modern Synthesis and Neo-Darwinism, see the article, The Modern Synthesis of Genetics and Evolution by Laurence Moran. His main points are summarized here.

There are three important differences between Modern Synthesis and Darwinism.

• Several mechanisms of evolution are recognized in addition to natural selection, including random genetic drift.
• Characteristics are inherited as discrete entities called genes. Variation within a population is due to the presence of multiple alleles of a gene.
• Speculation is (usually) due to the gradual accumulation of small genetic changes. This is equivalent to saying that macroevolution is simply a lot of microevolution.
  

Another good reference to check on this subject is Polymorphism and the History of Evolutionary Theory.

Go to top

This web site is a 1998 ThinkQuest Contest Semi-Finalist. Copyright © 1999 ThinkQuest Team 19012. All rights reserved. Last modified: Friday August 28, 1998.