Darwinian Natural Selection.

Natural selection is the powerhouse behind evolution, which over billions of years has resulted in the amazing diversity of living organisms which surround us today.  A cornerstone for understanding natural selection and evolution is the concept that random mutation alters the sequence of the nucleotide building blocks that make up DNA. Due to the accumulation of mutations, the natural populations of all organisms show physical variation, which is a consequence of the genetic variability between different individuals.

Since all organisms, human beings included, are integrated into the environment, those individuals that are better adapted to a certain environment will fluorish, a process described as natural selection. Natural selection will favour those individuals that are most suited to a particular environment, which results in the accumulation of advantageous changes within the population as a whole.  In the real world, any number of factors can contribute to the selection of a given individual, and understanding the contributions to the selection process of specific changes in the DNA is far from being completely understood.  This complexity has given rise to many misunderstandings, and argument continues about how evolution works and the role of evolution, particularly in human history.  

Using a principle that is analagous to natural selection, farmers breed from livestock which show some desired trait, and select those offspring in which this trait appears or is even strengthened. This process of selection and breeding for desired properties of animals and plants is nothing new. For millenia farmers have used these techniques to improve the grains and livestock which are grown in farms throughout the world. What distinguishes the modern approach used in biotechnology from these traditional methods of genetic improvement is both the degree of specificity and the speed at which novel traits may be derived, together with the diversity of novel features which may be introduced.

Can we simulates this powerful process in the laboratory? This is clearly an ambitious proposal, but if we can harness the power of natural selection then we have a powerful tool with which we can adapt living matter to solve everyday problems. Researchers have used their understanding of the underlying processes of mutation and selection to mimic the process of natural selection and have developed a methodology called "directed evolution".