Stupid Christian Article on Evolution

[Squeegee Beckenheim]

Maybe because asking you guys to deal in specifics and not vague assertions is something you yourselves should be doing in the first place.

Given your protracted dancing in the "facts" thread, this is probably your most ironic statement yet.

 

[Lowpro]

Does Randman consider improved reproductive rate due to selection of one species versus another population of the same species without that stress to be evolution in action?

 

[RecoveringYuppy]

So Simon, how do you explain the cheetah's relative low genetic variability? Shouldn't the cheetah be thriving now as populations are smaller? After all, you claimed smaller populations increase genetic variability.

No he didn't say that. You don't seem to understand that isolation doesn't imply reducing the population of species. It just means one or more groups become isolated. There is no requirment that the members they are isolated from die off.

 

[Halfcentaur]

I see randman is already rehashing his talking points and conveniently ignoring things he's already been shown. Especially regarding the rate of the accumulation of useful genes vs. gene loss.

Someone tell me that my mention of Dr. Rodin's (and earlier studies) wasn't a total waste of my time. Please?

He's in this for scoring hits to his bubble of religious assertion. The more doubts and disagreements, the more his world view is asserted in his mind.

This is a fantasy world, where the few who see the truth are up against a world majority of those who do not see the truth.

Amusingly, the world and all it's nations can agree to delude themselves in the name of the dogma of evolution and whatever is gained from not following what he insists is evident and clearly logical, but they can't seem to agree on anything else for the most part.

It seems Randman would have use think world peace could be attained if only we could shame the world's nations into agreeing with the idea of harmony, as his creationist agenda is only mocked as a superstitious fringe theory of pseudo science the world over because nobody wants to challenge the intellectual dogma that is evolutionary biology.

It's really a perfect way to have a superstition like his validated. The act of being doubted just dings the bell of persecution. If it wasn't such a feeble minded construct of denial, it would almost be genius.

 

[randman]

You don't seem to understand that isolation doesn't imply reducing the population of species. It just means one or more groups become isolated.

By definition, isolation decreases genetic genetic variability by eliminating the members of the parent species from the gene pool.

Evos have yet to show NeoDarwinian mechanims increase genetic variabilty faster than subgroup isolation decreases it. It's an unsubstantiated claim asserted as fact, by evos.

 

[quixotecoyote]

So Simon, how do you explain the cheetah's relative low genetic variability? Shouldn't the cheetah be thriving now as populations are smaller? After all, you claimed smaller populations increase genetic variability.

The quote in question.

It's not:
a) In general, evolution is a consequence of isolation rather than a cause of it. Isolation -> Genetic drift -> The two populations are too different too co-reproduce. If the populations are free to intermingle, there is no reason for such a genetic drift and it makes specification unlikely.
b) Microevolution does not cause reproductive isolation, by definition, because such isolation is a criterion for speciation and speciation defines macroevolution.
c) This isolation actually protect less prevalent alleles and variant that might be otherwise drowned in the more prevalent ones. As such, this evolution is actually increasing genetic diversity.

Or are you confusing microevolution and natural selection again?

The population being smaller has nothing to do with increasing genetic variability. The point is that the there are now multiple populations that are different. Two different groups subject to different selective pressures will select for different genes, leading to more variation than if one group had selected for one set of genes.

(eta: I'm a little wrong about this. The smaller the population, the more likely it is that random mutations will substantially alter the populations overall genetics; just genetic drift apart from selection pressures. That's not saying it makes it any better, and multiple isolated populations will be more varied still.)

 

[A'isha]

Randman somehow seems to be implying that isolating one population of a species from another population means that the genome of that species becomes suddenly unavailable to the gene pool of one of those populations.

 

[RecoveringYuppy]

By definition, isolation decreases genetic genetic variability by eliminating the members of the parent species from the gene pool.

No, it doesn't, for the very simple and easy to understand reason I just explained.

BTW it's doubly absurd to say that your claim is "by definition".

 

[randman]

No, it doesn't, for the very simple and easy to understand reason I just explained.

BTW it's doubly absurd to say that your claim is "by definition".

Wrong.

 

[quixotecoyote]

God, I'm off tonight. My brain is running about two posts behind my typing.

Genetic drift is not mutations, it's when a population gets so tiny it starts losing recessive alleles over the course of normal breeding.

 

[RecoveringYuppy]

Wrong.

Ok. So you're claiming that if we isolate some humans from the rest of the population, somehow genes are going to magically disappear from the rest of us? How do you propose that happens?

 

[RecoveringYuppy]

Evos have yet to show NeoDarwinian mechanims increase genetic variabilty faster than subgroup isolation decreases it. It's an unsubstantiated claim asserted as fact, by evos.

BTW putting aside your idiocy about the affects of isolation, we have plenty of measurements of mutation rates. In the human/chimp split the retained mutations in both lines are easily less, probably far less, than .1% of the total mutations that happened in the populations during that time.

 

[randman]

Some of you guys need to take an introductory high school or college biology course just to get the basic handle of evolution.

The present concept of evolution is a modification and elaboration of the Darwin's theory of natural selection, and is often called Neo-Darwinism.

According to the present concept, genetic variations appearing among the members of a population bring about evolution under the influence of natural selection and reproductive isolation. Thus, there are 4 factors in the present concept of evolution : genetic variations, natural selection, speciation, and reproductive isolation. Genetic variations form the raw material of evolution.

1. Genetic Variation in Population. The term population refers to all the individuals of a species inhabiting the same area at a particular time. ......It is the population that evolves, that is, changes over time, not its individual members.

Changes in Gene Frequencies. The total gene content of a whole species is referred to as the gene pool.....The change occurs in many ways : migration, nonran-dom mating, genetic drift, mutation, recombination and hybridization.

i) Migration. ....... Addition or removal of alleles when individuals join or leave a population from/to another locality causes gene flow.
.....

(iii) Genetic Drift. The term genetic drift refers to the chance elimination of the genes of certain traits when a section of population migrates or dies of natural calamity. It dramatically alters the gene frequency of the remaining population. It eliminates certain alleles and fixes the other alleles, thereby reducing the genetic variability of the population. For example, in case of snowstorm, the individuals having alleles (characters) that provide resistance to cold survive, whereas others die. The frequency of such alleles, which were hitherto of no value, may increase as they now have adtaptive value.

.....

Bottleneck Effect. Natural calamity, say earthquake, fire or flood, may greatly reduce the size of a population, killing the individuals randomly. The genetic pool of the small surviving population is often not a representative of genetic pool of the original population. This situation with reduced genetic variability is called bottleneck. Among the survivors, certain alleles may be overrepresented, some may be underrepresented, and some alleles may be totally eliminated (Fig. 7.58).

http://www.internationalskeptics.com/forums/showthread.php?p=6998274#post6998274

Of course, since the presentation talks mainly of NeoDarwinism, it avoids discussing the weakness of the theory, but note whenever they talk of a decrease in genetic variability above and think about it. Removing members from the breeding population, as occurs when a part of a population spits off by definition decreases genetic variability.

Note the following:

Speciation is not likely to occur simply by changes in the genotype of a population. The populations with different genotypes appearing in them must be isolated so that differences may accumulate to the level of speciation. Else interbreeding of emerging populations will result in mixing of their genotypes and disappearance of differences between them. Isolation preserves the integrity of a species by checking hybridisation.

So here you have what I am talking about (may want to read the whole chapter on the link). Genetic variability decreases (even dramatically) when you split off one group from another. Evos posit mutations can increase genetic variability, but the issue is the rate of beneficial mutations compared to the loss of genetic variability through subgroup isolation. Generally, this isolation is considered to occur prior to speciation, and of course, speciation itself is defined by reproductive isolation.

Hopefully, some can see why microevolution via NeoDarwinism does not suffice for the origin of the higher taxa.

 

[randman]

Ok. So you're claiming that if we isolate some humans from the rest of the population, somehow genes are going to magically disappear from the rest of us? How do you propose that happens?

No, but that subgroup will have just reduced it's genetic variability if that isolation continues.

 

[randman]

BTW putting aside your idiocy about the affects of isolation, we have plenty of measurements of mutation rates. In the human/chimp split the retained mutations in both lines are easily less, probably far less, than .1% of the total mutations that happened in the populations during that time.

So there is no reason for evos not to have backed up their claims then. They have plenty of studies of one side of the issue, mutational rates. So why no comparisons with expected loss of genetic variability which occurs via isolation of subgroups.

 

[quixotecoyote]

So there is no reason for evos not to have backed up their claims then. They have plenty of studies of one side of the issue, mutational rates. So why no comparisons with expected loss of genetic variability which occurs via isolation of subgroups.

Can you explain why there would be any overall loss of genetic variability which occurs via isolation of subgroup since the main group still exists?

 

[randman]

The quote in question.



The population being smaller has nothing to do with increasing genetic variability. The point is that the there are now multiple populations that are different. Two different groups subject to different selective pressures will select for different genes, leading to more variation than if one group had selected for one set of genes.

(eta: I'm a little wrong about this. The smaller the population, the more likely it is that random mutations will substantially alter the populations overall genetics; just genetic drift apart from selection pressures. That's not saying it makes it any better, and multiple isolated populations will be more varied still.)

your comment

The population being smaller has nothing to do with increasing genetic variability.

That's right. It decreases genetic variability by definition due isolation from other former breeding members.

The point is that the there are now multiple populations that are different. Two different groups subject to different selective pressures will select for different genes, leading to more variation than if one group had selected for one set of genes.

There is morphological change, sure, but each group is genetically less variable than they were as one population.

The smaller the population, the more likely it is that random mutations will substantially alter the populations overall genetics;

Yes, and that's because in a larger population mutations would wash out, and also because the genetic variability has decreased so adding a new change is more likely to have an impact.

just genetic drift apart from selection pressures. That's not saying it makes it any better, and multiple isolated populations will be more varied still.)

Genetic drift leads to less variability. Multiple isolated populations may be varied but the process of isolation decreases their genetic variability as a population.

 

[randman]

Can you explain why there would be any overall loss of genetic variability which occurs via isolation of subgroup since the main group still exists?

Simple. If they remain isolated, the main group is irrelevant to the isolated population's genetic variability. If they do not continue in a process of isolation, they are not likely to evolve into a new species.

 

[quixotecoyote]

your comment



That's right. It decreases genetic variability by definition due isolation from other former breeding members.



There is morphological change, sure, but each group is genetically less variable than they were as one population.

Is is only true if enough members left so that certain alleles were removed from one of the groups. If all alleles present before the split are present after, there's no decrease in variation. So, not definitional.

Yes, and that's because in a larger population mutations would wash out, and also because the genetic variability has decreased so adding a new change is more likely to have an impact.

You seem to get that it's population size here.

Genetic drift leads to less variability. Multiple isolated populations may be varied but the process of isolation decreases their genetic variability as a population.

I already corrected and clarified re genetic drift. It's happens with small population size, regardless of isolation.

 

[Resume]

Hopefully, some can see why microevolution via NeoDarwinism does not suffice for the origin of the higher taxa.

Are you published somewhere? Answers in Genesis doesn't count.