Monday, August 02, 2010

An Unanswered Question

13 comments:

Sarah Carr said...

Moftases says this:

http://en.wikipedia.org/wiki/Mutation

Will E. said...

Yeah, that's what they all say, but mutations are comprised of changes that are almost always harmful to the organism. They can happen by accident or when exposed to radiation.

It's a mainstream idea that evolution is a result of this, but when examining it practically and scientifically there has been little to support that a random mutation contributes to evolution.

Sarah Carr said...

Via Moftasa: "The influenza virus mutates every year to its own advantage".

Will E. said...

That's funny that the example is of something that is harmful mutating to something even more harmful.

Besides, there is something called variation that alters the DNA components and not structure.

Humans? and don't tell me sickle cell anemia.

Sarah Carr said...

"This doesn't mean that the flu example is wrong. It's also the mechanism of antibiotic resistance in bacteria. And as for variation, well mutations are one source of variation (also sexual reproduction produces variation and genetic drift). Natural selection is basically, the existence of variation between organism, differential reproduction and heredity.

As for humans, yes sickle cell anemia is a good example. A common misconception is that evolution produces perfect results or "survival of the fittest". It just produces the survival of the fit enough".

Will E. said...

Again the whole evolution debate... the answers seem like a sort of dogma now. Sickle cell anemia isn't good. It's a disease.

Of course there's no such thing as survival of the fittest in evolution, it's natural selection. Yet isn't it peculiar that all these mutations match their environment.

There's a difference between variation and mutation. But variation doesn't lead to evolution of species.

Evolution is about a certain species reproducing independently. That's the main reason for the much ignored Forsdyke paradox.

Mo said...

Mutation is local change which is not always passed on to the offspring. It's rarely positive, but still in some cases mutation can be useful, it may create new protein that is resistant to bacteria for example.

A more effective process to evolutionary change in complex organisms is transposon which may lead to increase or decrease of the DNA sequence.

Evolution is not directed towards only producing a successful product or organism, but those which happened to be fit are the result of positive evolution.

Will E. said...

Thanks Mo for exemplifying that the question remains unanswered and is a matter of debate.

Sarah Carr said...

"Yes, sickle cell anemia is a genetic disease but it keeps people from dying from malaria. So people who developed it survived and passed it on to their off-springs. So the Sickle cell mutation contributed to a variation in the population of humans.

What's wrong with the mutations matching the environment?"

Mo said...
This comment has been removed by the author.
Mo said...

Mutation, transposon or jumping genes, breading are all answers to causes of DNA changes.

I am not sure what is the Forsdyke paradox.

Will E. said...

"What's wrong with the mutations matching the environment?"

If you can't figure it out on your own then nothing I can say will make you see what's wrong.

Mo said...

This is a long term running experiment shows evolution in action:

http://en.wikipedia.org/wiki/E._coli_long-term_evolution_experiment