Changes
A modest beginning
The above is subject to change as far as structure is concerned. [[User:Karajou|Karajou]] 00:30, 24 April 2007 (EDT)
== Introduction ==
The Theory of Evolution is a scientific theory which seeks to explain the existence of the myriad species which are found on the Earth today without resort to supernatural explanations (such as the intervention of a God or gods). Accordingly, the theory is strongly opposed by those who believe that all animals (including man) were designed and created by such a supernatural being.
The theory is essentially based on two observations: (1) that all living things are involved in a struggle for survival; and (2) that all living things can pass on their characteristics to their offspring. It relies upon the combined operation of two processes generally referred to as natural selection and genetic mutation.
Natural selection proposes that in nature some living things will do better than others and, in doing so, will survive to produce more offspring. As a result, over time the characteristics of those more successful individuals will become more common in the population.
Genetic mutation is a process which allows for a physical difference to exist between an individual and its offspring. Differences which arise as a result of genetic mutation are chance events and most such differences are unlikely to be advantageous to the offspring.
The Theory of Evolution proposes that over a very long period of time the differences brought about by mutations which are found to be advantageous (through the process of natural selection) will result in the development of new species.
== History ==
The Theory of evolution has itself evolved over time.
It has long been observed that parents can pass their physical characteristics on to their offspring. Farmers have bred animals on that basis for many centuries and they, along with, for example, dog and horse breeders, continue to do so today.
The mechanism by which those characteristics are acquired and passed on was only discovered relatively recently, but theories have existed for some time. One such theory was proposed by Jean Baptiste de Lamarck (1774 - 1829). He believed that animals could acquire physical characteristics during their lifetime and then pass them on to their offspring<ref>''Philosophie zoologique ou exposition des considérations relatives à l'histoire naturelle des animaux'' (1809)</ref>.
==References==
<references/>
*Campbell, Niel A. and others. ''Biology, Concepts and Connections'', Fifth Edition, Pearson Education, San Fransico, CA (2006).
