Complexity & Evolution...

[allan175]

Also, as I said before, increasing complexity is just a side effect of evolution. The primary idea of evolution is that the better adapted a species is to its environment, the more likely it is to survive.

This line caught my eye in the debate forum.

I've just recently finished reading "Life's Grandeur" by Stephen Jay Gould.

It was quite interesting and, I think, showed that increasing complexity is not actually a side effect of evolution at all! It did drag a bit in places (there is a lot about baseball in there) but on the whole I quite enjoyed it.

[lilphil1989]

Also, as I said before, increasing complexity is just a side effect of evolution. The primary idea of evolution is that the better adapted a species is to its environment, the more likely it is to survive.

This line caught my eye in the debate forum.

I've just recently finished reading "Life's Grandeur" by Stephen Jay Gould.

It was quite interesting and, I think, showed that increasing complexity is not actually a side effect of evolution at all! It did drag a bit in places (there is a lot about baseball in there) but on the whole I quite enjoyed it.

I suppose it depends somewhat on your definition of complexity (something we've discussed at length before, so won't do here :p ).

In general though, I think complexity may increase or decrease, whichever makes the organism more likely to survive.

[allan175]

In general though, I think complexity may increase or decrease, whichever makes the organism more likely to survive.

Yes, but the argument he presented was that there was no general drive to complexity. Local adaption is just that, local.

[Giff]

Evolutiuion is very expermintal. Sometimes it's good for some species to be very primitive and brutal like the Mantis which is one of the earths most advance creature and the best constructed predator.

Complexity which humans have in form of complex social activities, speaking, a highly advanced brain and so on can be a huge advantage. Which we have seen. But it also have it's negative sides. A comples brain causes depression, mental illness, evil and so on. THis is shown on animals as schimpansies and dolphins.

If you look at exitincted species are there alot of complex lifes which had someting that gave them a huge advantage. But that advatange was the thing that finally got them extinct. Like a huge horn or a being very strong and big or some other thing. That finally become a burden in some situations.

A species that can adapt to it's enviorment is the most primary for species. Humans are one of the best, then are some much more primitive that are as good or perhaps even better.

As the first quoute you had Allan is complexity just a bi-product, or a side-effect as it accutally says. With complexity and a huge advantage comes great problems, like deceases and other things I mentioned.

[Kyuuketsuki]

Evolutiuion is very expermintal. Sometimes it's good for some species to be very primitive and brutal like the Mantis which is one of the earths most advance creature and the best constructed predator.

I wouldn't say it was "experimental" because that implies a sort of testing/design type concept ... there are various mechanisms required for evolution to occur and to continue occurring. Mechanisms that increase genetic diversity (Natural Selection, Sexual Selection & Genetic Drift) and mechanisms that decrease it (Mutation, Recombination & Gene Flow):

Natural Selection (Decrease)
Natural selection (see Biston betularia example above) is considered to be the mechanism by which a given organism type within a population have more offspring than others. Less fit animals get killed or simply have no offspring. "Fitness" should not be confused with the common human notion of physical fitness ... "fitness" means adaptation to a given environment. It is also worth noting that individuals amongst a population have a tendency to self-select either by sex or by other factors.

Sexual Selection (Decrease)
Many species (including humans) "choose" their mates and various mechanisms have evolved to use this selective pressure. Sexual selection tends to be self-limiting ... in some species the male can be seen to attract the female by impressive display (e.g. the peacock) but, negatively, that display also decreases the chance of the animals survival. In such cases evolution balances between increased attraction (and thus reproduction) and vulnerability to predators (death).

Genetic Drift (Decrease)
Genetic drift is the change in allele frequency due to chance alone and is a "binomial sampling error of the gene pool". In smaller populations the rate of allele change is greater whereas larger ones have more alleles in the gene pool but lose them more slowly. When a population decreases rapidly in size the remaining alleles may not be representative of the species as a whole and significant genetic drift can be seen to have occurred ... this is known as the "founder effect".

Mutation (Increase)
During the DNA copying process mistakes can be made. A single genetic "letter" might be changed a sequence of code added or deleted or genes can become inverted. The rate of mutation is between 10*10^-10 and 10*10^-12 to 1 per base pair/per generation. Most of these are non-advantageous leading to changes in the shapes of proteins (potentially destroying its function) but some (very few) are potentially advantageous. The ratio of advantageous to disadvantageous change is unknown and likely varies with respect to the organism's environment.

Recombination (Increase)
Recombination ("gene shuffling") occurs during meiosis and creates new combinations of alleles.

Gene Flow (Increase)
Gene flow is the introduction of new genes into a gene pool for instance the addition of a mate from one population into another non-related one.

All of these are non-intelligent so whilst I think I understand what you are getting at I wouldn't call evolution "experimental".

Kyu

[Giff]

Evolutiuion is very expermintal. Sometimes it's good for some species to be very primitive and brutal like the Mantis which is one of the earths most advance creature and the best constructed predator.

I wouldn't say it was "experimental" because that implies a sort of testing/design type concept ... there are various mechanisms required for evolution to occur and to continue occurring. Mechanisms that increase genetic diversity (Natural Selection, Sexual Selection & Genetic Drift) and mechanisms that decrease it (Mutation, Recombination & Gene Flow):

Natural Selection (Decrease)
Natural selection (see Biston betularia example above) is considered to be the mechanism by which a given organism type within a population have more offspring than others. Less fit animals get killed or simply have no offspring. "Fitness" should not be confused with the common human notion of physical fitness ... "fitness" means adaptation to a given environment. It is also worth noting that individuals amongst a population have a tendency to self-select either by sex or by other factors.

Sexual Selection (Decrease)
Many species (including humans) "choose" their mates and various mechanisms have evolved to use this selective pressure. Sexual selection tends to be self-limiting ... in some species the male can be seen to attract the female by impressive display (e.g. the peacock) but, negatively, that display also decreases the chance of the animals survival. In such cases evolution balances between increased attraction (and thus reproduction) and vulnerability to predators (death).

Genetic Drift (Decrease)
Genetic drift is the change in allele frequency due to chance alone and is a "binomial sampling error of the gene pool". In smaller populations the rate of allele change is greater whereas larger ones have more alleles in the gene pool but lose them more slowly. When a population decreases rapidly in size the remaining alleles may not be representative of the species as a whole and significant genetic drift can be seen to have occurred ... this is known as the "founder effect".

Mutation (Increase)
During the DNA copying process mistakes can be made. A single genetic "letter" might be changed a sequence of code added or deleted or genes can become inverted. The rate of mutation is between 10*10^-10 and 10*10^-12 to 1 per base pair/per generation. Most of these are non-advantageous leading to changes in the shapes of proteins (potentially destroying its function) but some (very few) are potentially advantageous. The ratio of advantageous to disadvantageous change is unknown and likely varies with respect to the organism's environment.

Recombination (Increase)
Recombination ("gene shuffling") occurs during meiosis and creates new combinations of alleles.

Gene Flow (Increase)
Gene flow is the introduction of new genes into a gene pool for instance the addition of a mate from one population into another non-related one.

All of these are non-intelligent so whilst I think I understand what you are getting at I wouldn't call evolution "experimental".

Kyu

Didn't really mean that it acctually is experimental. But it become in some ways like that. That's why some species suceed and other fail. But I agree with you. Evolution don't have a test/design type concept.

I just use the word as an expression, not that it really was. understand that it could be misunderstod.

[leo-rcc]

there are various mechanisms required for evolution to occur and to continue occurring. Mechanisms that increase genetic diversity (Natural Selection, Sexual Selection & Genetic Drift) and mechanisms that decrease it (Mutation, Recombination & Gene Flow):

I agree with what you said, but I think you turned the increase and decrease around here.

Just to be clear on this.

[Kyuuketsuki]

I agree with what you said, but I think you turned the increase and decrease around here.

That's very likely knowing me

Kyu

[leo-rcc]

NewScientist has made a brilliant article "Evolution: 24 myths and misconceptions "

http://www.newscientist.com/article/dn13...tions.html

One of the sub-articles is on the myth "natural selection leads to ever greater complexity"

http://www.newscientist.com/article/dn13...exity.html

A nice one to bookmark should you ever need to counter a Creationist.

[Giff]

The theory that life on earth came from mars is quite intresting.