Mutation

[Advaithi]

Evolution of Species including human race is consequence of mutations. Mutations are consequence of improper replications. Well, the question is the mutations are just accidental or they are made intentionally by the speices to make themselves as "The Fittest"?

[lemur]

I don't think organisms can intentionally mutate in a way that makes them "fitter" but maybe you could say that everything organisms do is in the interest of their survival, so any mutation-causing factors they would become exposed to would be a consequence of that. Is that too much of a stretch?

[Ophiolite]

I don't think organisms can intentionally mutate in a way that makes them "fitter" but maybe you could say that everything organisms do is in the interest of their survival, so any mutation-causing factors they would become exposed to would be a consequence of that. Is that too much of a stretch?

Yes, it is too much of a stretch.

Firstly, everything organisms do is not in the interests of their survival. For that to be true they would have to be omniscient in order to choose the best option of action out of those available. This is clearly not the case.

Secondly, the majority of mutations are truly random. Comparatively few circumstances induce a mutation rate significantly above the average.

[Horza2002]

Organisms can't change their DNA so that they are perfectly adapted to the enviroment they are in. All mutations do is provide an alternative to a current characterists (e.g. colour of fur). If this happens to be better than before then its good, if its not then it tends not to be spread amongst the population in further generations. Just remember though, that a lot of mutations are "silent". The change in the DNA sequence has no effect on the characterisic (point mutations)

[Maximus Semprus Veridius]

Yeah I would largely agree with lemur's point, that organisms just do what they need to survive (not taking the point to literally *Looks at Ophiolite*). They wouldn't suddenly change if the need is not there however. Say, for example, that a beetle lives in the area south of the sahara, where there is a lot of vegetation. The beetles distribution becomes more widespread due to a growing population. They move north into a hotter, drier environment. This would mean the beetles with adaptaions (mutations) to suit to environment (fitness) would happen to survive. So, you see, that the mutations are completely random (I think that may even be in the definition of biological mutation - I would look that one up though), but they bring benefits that seem as though they have been "consciously", or "willfully" precipitated.

[NTettamanti]

Evolution is not teleological. There exists no end goal for how we evolve; I do not exist to try to become the 'fittest'. Instead, if the way my genes intermix with the environment increases my survivability then I will potentially have a child that contains some of those same genes. Therefore, I would imagine that mutations are accidental. Imagine the complexity of the biochemical reaction that produces any organism; it's almost inevitable that there will be some random changes. Due to the fact that DNA is not sentient, however, I would imagine that these mutations are accidental.

 

If every piece of genetic information wanted to be copied, then if they "had the choice" they would have no mutations because "they" would "want" to retain their own information. Currently there are numerous examples in the animal kingdom where organisms do not utilize DNA, but DNA 'utilizes' the organisms for its own replication. Think about a bee or ant colony, the sterile ‘worker’ organisms only exist to provide a means to raise and take care of the eggs laid by the queen. The worker organisms don’t exist to perpetuate their own biological selves; in fact, they give up their own reproduction to facilitate the raising of another individual’s young. When viewing biology through the lens of individuals reproducing, this would make no sense. However, when organisms exist to replicate information that they possess, the picture becomes perfectly clear. The workers in these colonies contain strands of DNA that instruct them to tend to the queen. While most of the organisms that possess this gene don’t survive, the gene itself survives through the queen’s prosperity. Survival of the fittest implies the fittest gene, not the fittest organism (which acts only as a vehicle for the gene), will perpetuate its survival. Under this paradigm, it would also make no sense for DNA to induce mutation because DNA does not act in any teleological way for the organism, but rather for itself.

 

PS, sorry for the personifcation of DNA. It's difficult to explain in a manner that isn't personified, obviously genes do not 'want' or 'attempt' anything, they simply do so because of (in my opinion at least) complex biochemical reactions.

Edited April 22, 2011 by NTettamanti