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Mutations and Evolution


Its often not grandiose, overlapping theories such as the Neutral Theory of Evolution, or Modern Synthesis, that biologists work with in their research on a day-to-day basis. Instead, it is the beautiful basics of genetics that are the cornerstone of experiments. The basics are then used to reflect on bigger ideas, such as population ecology and evolution. It is the beautiful basics of genetics with which we concern ourselves in this section.

Every organism has a set of genes and half of the genes of that organism come from each parent. The combinations of the genes causes the variation of individuals within the species. The genes of a butterfly, an ape or a fowl carry the code that determines the appearance and the character of the butterfly, the ape and the fowl. The genetic code allows an overwhelming variety within the species of the kind. A mutation is basically a gene that has an abnormality in relation to its normal configuration. The abnormality can then be passed to successive offspring, thereby producing a marked difference. There are many different types of mutations. The smallest possible genetic mutation is a 'point-mutation'. This occurs in the DNA when the base-pairs combine with the 'wrong' partner. Multiple point-mutations are common and are found to increase substantially by the effect of mutagens. Mutations are, of course, heritable and these can extend to whole or part chromosomal mutations. Because many genes are affected by a chromosomal mutation, these often have drastic ramifications on the offspring.

Ethical Issues

There many ethical issues with cloning, and genetics in general. In the United states, many supermarkets are already selling Genetically Modified foods. Most of the produce usually creates its own pesticide that will eat the insects from the inside out, a trait borrowed from a group of bacteria that, to our knowledge, has no adverse affects on humans. The ethical issue comes into play here: most supermarkets do not advertise these foods as Genetically Modified. Even though no adverse affects are known to date, not allowing the customer to know that they are purchasing GM foods is controversial. There are two main sides of the argument: 1) GM foods won't harm you, so why tell the people? If they have adverse affects once you tell them, it could be a self-fulfilling prophecy. 2) Even if it won't hurt us, you should still tell us so we have a choice in the matter. That's like giving us a certain drug without telling us: it's not ethical. If you go into your local supermarket and ask the General Manager if they know whether GM foods are being sold, the answer will probably be a resounding "No", since there is no separate signing for these foods. This reflects an underlying problem with the genetically-modified food discussion. Which foods are genetically modified? Many seedless fruits exist as a result of primitive genetic manipulation in the form of accelerated artificial selection. Products such as corn and apples could not exist without human intervention in the form of breeding and cross-species grafting. If we place the boundary at the laboratory door, we demonize certain foods that have saved billions of lives, specifically golden rice and others with which we have become perfectly comfortable. The main issue with the w:genetically modified foods is that their long term effect on the Earth's ecosystem is unknown. To improve a plant by natural selection took a long time and there was time for the ecosystem to adapt. Cloning endangered species may be a good idea to keep the ecosystem in balance.
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