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Author Topic:   Why Darwinism is wrong
mick
Member (Idle past 4986 days)
Posts: 913
Joined: 02-17-2005


Message 211 of 305 (207435)
05-12-2005 12:43 PM
Reply to: Message 210 by Jianyi Zhang
05-12-2005 12:37 PM


Re: The return of Lamarkian evolution is imminent !
Hi Jianyi,
Your hypothesis does sound pretty similar to RMNS to me.
First you have a gross mutation. So we agree on the importance of random mutation.
Then carriers of the mutation have to reproduce. if they can't find partners who share the gross mutation (i.e their twins, or whatever) or if they can't reproduce asexually, can't have virgin births, then they go extinct and the gross mutation is lost from the gene pool . So we agree on natural selection. This is the strongest form of natural selection - reproduction or extinction.
so your model is: random mutation + natural selection.
Mick

This message is a reply to:
 Message 210 by Jianyi Zhang, posted 05-12-2005 12:37 PM Jianyi Zhang has replied

Replies to this message:
 Message 215 by Jianyi Zhang, posted 05-13-2005 1:25 AM mick has not replied

Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 212 of 305 (207437)
05-12-2005 12:47 PM
Reply to: Message 210 by Jianyi Zhang
05-12-2005 12:37 PM


Re: The return of Lamarkian evolution is imminent !
Underlying assumption is that mutanted plants is a new species of plant.
This assumption is still completely unwarranted.
TTFN,
WK

This message is a reply to:
 Message 210 by Jianyi Zhang, posted 05-12-2005 12:37 PM Jianyi Zhang has replied

Replies to this message:
 Message 213 by Jianyi Zhang, posted 05-12-2005 1:46 PM Wounded King has replied

Jianyi Zhang
Inactive Member


Message 213 of 305 (207455)
05-12-2005 1:46 PM
Reply to: Message 212 by Wounded King
05-12-2005 12:47 PM


Re: The return of Lamarkian evolution is imminent !
This assumption is still completely unwarranted.
How about assuming it a new species? How kind of role for NS in its arrival?

Jianyi Zhang

This message is a reply to:
 Message 212 by Wounded King, posted 05-12-2005 12:47 PM Wounded King has replied

Replies to this message:
 Message 217 by Wounded King, posted 05-13-2005 4:56 AM Jianyi Zhang has replied

Jianyi Zhang
Inactive Member


Message 214 of 305 (207607)
05-13-2005 1:09 AM
Reply to: Message 209 by EZscience
05-12-2005 12:22 PM


Re: Mutant clusters as mechanism of speciation
Originally posted by EZscience:
I did raise the challenge about inbreeding depression in the progeny of your 'clustered mutants' as applied to higher animals that you haven't really addressed.
In post 196, I wrote:
Even the majority of super-twins died initially, some of them would survive. If they did not survive, you never see them, what we see in the world is ones survived.
In fact, many animals survive inbreeding. For example, Jackson Lab keeps over 3000 inbreeding mice, they are created technically (transplant mice).
In my website, I have following writing:
First generation is supertwins brother-sister from the same birth, they mate to have the second generation, brother-sister from the same parents (assuming only twins parent); their offspring are brother-sister from different parents.
If an organism has a few weeks in the life cycle, it only takes a couple of years for them to have over 20 life cycle. By then, majority of the members in the organism will be remote-related.
EZscience wrote:
And, I also do not see how novel sources of heritable variation can negate the validity of natural selection in any way, whether they happen to sometimes generate new species or not.
The products will all be subjects of natural selection.
Nobody completely negates the validity of natural selection, the model say NS not involved with arrival of products, but all products will be subject to natural selection. That is huge difference. NS is a filter, not an generator.
EZscience wrote:
And I don't think you should extrapolate too much generality of applicability for your mechanisms yet.
I think they are unlikely to be important in higher animals that are obligately outcrossing.
You certainly can have your opinion.
This message has been edited by Jianyi Zhang, 05-13-2005 01:10 AM

Jianyi Zhang

This message is a reply to:
 Message 209 by EZscience, posted 05-12-2005 12:22 PM EZscience has not replied

Jianyi Zhang
Inactive Member


Message 215 of 305 (207611)
05-13-2005 1:25 AM
Reply to: Message 211 by mick
05-12-2005 12:43 PM


Re: The return of Lamarkian evolution is imminent !
Originally posted by mick:
Your hypothesis does sound pretty similar to RMNS to me.
It sounds similar, in fact, they differ greatly.
First you have a gross mutation. So we agree on the importance of random mutation.
Gross mutation may create a new species by itself without natural selection, do you agree?
so your model is: random mutation + natural selection.
My model is:
random mutation generates everything without NS,
natural selection eliminates unfitted.
This message has been edited by Jianyi Zhang, 05-13-2005 09:35 AM
This message has been edited by Jianyi Zhang, 05-13-2005 09:36 AM

Jianyi Zhang

This message is a reply to:
 Message 211 by mick, posted 05-12-2005 12:43 PM mick has not replied

Ben!
Member (Idle past 1398 days)
Posts: 1161
From: Hayward, CA
Joined: 10-14-2004


Message 216 of 305 (207622)
05-13-2005 2:31 AM
Reply to: Message 1 by Jianyi Zhang
04-26-2005 11:57 AM


Jianyi,
This thread seems both a discussion of Darwinism AS WELL AS a discussion of your "super-twinning" model of speciation. I'd like to ask a question about your "super-twinning" hypothesis.
I'm not a biologist at all; I haven't completed an introductory to biology course at all yet. So I may be asking an uneducated question. This is a really simple question about allele frequencies and "super-twinning"
It seems to me that, if you're right, and if a species were instantly created by the simultaneous birth of fraternal twins with the same gross mutations, that there's some really clear predictions about allele frequencies in the resulting species (which would proliferate, if selected by the filter of NS, from these two "second-level" Eves)
The prediction is specifically that the allele frequencies in the parent species' population would be changed. For example, a genotype whose alleles had 50% probability in the parent's species have a 62.5% chance of changing drastically (12.5% chance that the variation will be completely eliminated, 50% chance that one of the alleles will INSTANTLY become 75% probable). Note that I didn't map this into phenotypes, ... maybe that would help clarify things.
Anyway, seems to me that this instant change in allele frequencies in the new species, as compared to that of the parent species, should be observable. However, a RMNS speciation model would predict nothing special, just regular drift / change rates of alleles due to population drift or selection principles.
Have there been any measurements similar to this that have been done? For example, comparing allele frequencies of homologous genes between two species believed to have a common ancestor (especially those who are thought to have speciated "recently").
Is this just nonsense?
-------------
The numbers (model is for a phenotype controlled by a single gene with two alleles, both with frequency 50% in the parent population)

MOM
| A(50%) | a(50%)
------+--------+--------
D A(50%)| AA(25%)| Aa(25%)
A ------+--------+--------
D a(50%)| AA(25%)| aa(25%)
Now, this is going to be true for each twin. So, here are the
overall percentages for each twin:
Twin 1 Twin 2
-----------------------------------------------
Allele elminated: 12.5%
---------------------
aa (25%) aa (25%) -> both aa (6.25%)
AA (25%) AA (25%) -> both AA (6.25%)
--------------------------------------------
"a" freq = "A" freq = 50%, in pop: 37.5%
---------------------
aa (25%) AA (25%) -> 6.25%
AA (25%) aa (25%) -> 6.25%
[a,A](50%) [a,A] (50%) -> 25%
--------------------------------------------
one allele's frequency in pop set at 75%, (50%)
the other allele's frequency in pop set at 25%:
aa (25%) [a,A] (50%) -> freq("a")->75% (12.5%)
AA (25%) [a,A] (50%) -> freq("A")->75% (12.5%)
[a,A](50%) aa (25%) -> freq("a")->75% (12.5%)
[a,A](50%) AA (25%) -> freq("A")->75% (12.5%)
This message has been edited by Admin, 05-17-2005 10:22 AM

This message is a reply to:
 Message 1 by Jianyi Zhang, posted 04-26-2005 11:57 AM Jianyi Zhang has replied

Replies to this message:
 Message 218 by Jianyi Zhang, posted 05-13-2005 2:15 PM Ben! has not replied

Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 217 of 305 (207650)
05-13-2005 4:56 AM
Reply to: Message 213 by Jianyi Zhang
05-12-2005 1:46 PM


circling
Is this ever going to go anywhere?
I point out that you are making a totally unwarranted assumption and your only comeback is to say that we should still assume it and then your argument will make sense?
Your theory simply seems to want to choose an extreme hopeful monster like scenario and then to get around the obvious problems with such a scenario resort to an even more unlikely mechanism of supertwinning. You also assume that incest would be natural, another assumption with little support. If the reproductive isolation was post-mating then why would the MISTWGM need to resort to incest? How different morphologically are you proposing these hopeful monsters of yours are?
TTFN,
WK

This message is a reply to:
 Message 213 by Jianyi Zhang, posted 05-12-2005 1:46 PM Jianyi Zhang has replied

Replies to this message:
 Message 219 by Jianyi Zhang, posted 05-13-2005 4:36 PM Wounded King has replied

Jianyi Zhang
Inactive Member


Message 218 of 305 (207781)
05-13-2005 2:15 PM
Reply to: Message 216 by Ben!
05-13-2005 2:31 AM


Originally posted by Ben:
I'm not a biologist at all; I haven't completed an introductory to biology course at all yet.
Ben, that means you has not been poisoned.
It seems to me that, if you're right, and if a species were instantly created by the simultaneous birth of fraternal twins with the same gross mutations, that there's some really clear predictions about allele frequencies in the resulting species (which would proliferate, if selected by the filter of NS, from these two "second-level" Eves)
If I am right, there are no significant differences in majority of allele frequencies. Except in cases like chromosomal translocation or chromosomal fusion, ones can see addition or deletion of many genes if comparing parental and resulted species.
I suspect many gross mutation or gross changes of genetic materials caused by viral transfers, which can add or delete a piece of chromosome instantaneously.
Study of allele frequency is not best way to detect that, proper way to do it is by sequencing whole genome.
The prediction is specifically that the allele frequencies in the parent species' population would be changed.
The allele frequencies of parent species' population will be as usual,
most of the allele frequencies of new species' population will be same as parental ones. Ones will see some new genes added in new species, some genes are gone completely.
However, a RMNS speciation model would predict nothing special, just regular drift / change rates of alleles due to population drift or selection principles.
You are right, changes of allele frequencies is just like changes of pollen density in air, it is unavoidable. RMNS has not any predictory power at all in terms of speciation. You are much smarter than ones with many year biology training.

Jianyi Zhang

This message is a reply to:
 Message 216 by Ben!, posted 05-13-2005 2:31 AM Ben! has not replied

Jianyi Zhang
Inactive Member


Message 219 of 305 (207867)
05-13-2005 4:36 PM
Reply to: Message 217 by Wounded King
05-13-2005 4:56 AM


Re: circling
Originally posted by Wounded King:
I point out that you are making a totally unwarranted assumption and your only comeback is to say that we should still assume it and then your argument will make sense?
Even ones do not know it a real new specie, I just make a hypothetical case, ask you a simple question. Why are you so afraid and tongue-tied with the assumption?
Your theory simply seems to want to choose an extreme hopeful monster like scenario and then to get around the obvious problems with such a scenario resort to an even more unlikely mechanism of supertwinning.
How do you know it unlikely? By your wishful thinking?
You also assume that incest would be natural, another assumption with little support.
What kind supports do you like to see?
If the reproductive isolation was post-mating then why would the MISTWGM need to resort to incest?
The MISTWGM does not have to incest, they can mate with parental species, however, there is no healthy offspring, or no offspring at all, as they are different biological species. They only can have healthy offspring by mating among themselve.
How different morphologically are you proposing these hopeful monsters of yours are?
They do not have to be very morphologically different, birds can recognize other birds by songs, and they might be morphologically very similar. If a new species does not have systems to find out each other, they do not survive, and ones never know.

Jianyi Zhang

This message is a reply to:
 Message 217 by Wounded King, posted 05-13-2005 4:56 AM Wounded King has replied

Replies to this message:
 Message 220 by Wounded King, posted 05-17-2005 5:25 AM Jianyi Zhang has not replied
 Message 222 by mick, posted 05-18-2005 8:17 PM Jianyi Zhang has replied

Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 220 of 305 (208957)
05-17-2005 5:25 AM
Reply to: Message 219 by Jianyi Zhang
05-13-2005 4:36 PM


Re: circling
Even ones do not know it a real new specie, I just make a hypothetical case, ask you a simple question. Why are you so afraid and tongue-tied with the assumption?
Why bother? It is already established that selfing organisms can effectively undergoe speciation in a single generation via hybridisation or polyploidy. What fudamental difference is one more mechanism, and one there is absolutely no reason to assume has caused speciation in a single generation, going to make?
How do you know it unlikely?
Well why not provide some evidence of it's likelihood? What is the prevalence of 'supertwinning' in different animal populations? Presumably you could make a rough estimate if you know the rates of production of monozygotic twins of different sexes and survival of embryos after 'significant' levels of genomic/chromosomal reordering. Then you could show the incidence rates of incest in those same populations.
Now if your 'bottleneck' is a true bottleneck for the ancestral population rather than just an artifact of the genetics involved in 'twinning' then even with totally random mating you might have some inbreeding with a small enough population, but in a moderately large population with random mating the chances are much poorer, and poorer still if they occur in a animal which tends to avoid incest.
It is all of these factors that predispose me to think that it is an unlikely situation.
What kind supports do you like to see?
Something resembling a coherent mechanism and some idea of how constituent parts of that mechanism are know to operate. As I said, it is not unknown for monozygotic twins of different sexes to be born, but if you knew the frequency then you might have a basis for calculating the likelihood of 'supertwinning'. Unfortunately in human cases of monozygotic twins of different sexes the female suffers from Turners syndrome, due to loss of a Y chromosome making her XO, but this need not be the case for other animals.
They do not have to be very morphologically different, birds can recognize other birds by songs, and they might be morphologically very similar. If a new species does not have systems to find out each other, they do not survive, and ones never know.
Indeed and this sort of pre-mating isolation has been shown to be mediated by both culturally learned behaviours and geneticaly determined sexually selected characteristics (Grant and Grant, 1997), not forgetting that song itself may be determined by genetics in some species. In what way does this have any relevance to your hypothesis? If only a small change is needed then why is a point mutation not a sufficient level to start at?
If anything cultural inheritance of song as a mechanism of pre-mating isolation provides a Lamarckian mechanism of speciation and certainly doesn't offer support for your hypothesis.
TTFN,
WK

This message is a reply to:
 Message 219 by Jianyi Zhang, posted 05-13-2005 4:36 PM Jianyi Zhang has not replied

Replies to this message:
 Message 223 by EZscience, posted 05-18-2005 9:50 PM Wounded King has not replied

wnope
Inactive Member


Message 221 of 305 (209200)
05-17-2005 10:46 PM
Reply to: Message 1 by Jianyi Zhang
04-26-2005 11:57 AM


Not sure what your point is
To be honest, I can't quite see how what you are proposing challenges Neo-Darwinistic speciation theory.
1. Different species has different chromosomal karyotypes
-It's called mutation. The Nylong Bug is a good example of a frameshift mutation resulting in a new, surviving species. Neo-Darwinism isn't just allele frequencies, or it couldn't account for the rise of new traits. Also, cross-over in Meiosis can sometimes shift homeotic complexes and other gene groups. Non-disjunction (change in chromosone number) is also a result of cross-over. You seem to be completely ignoring the genetic component of Neo-Darwinism. In fact, you seem to be referring to plain Darwinism.
2. Against all scientific evidences so far available
-Ironically, polyploidy is the usual example for mechanical speciation. Endosymbiosis, however, isn't really driven by evolutionary mechanisms. It was simply the establishment of a symbiotic relationship between two prokaryotes.
Speciation was documented several times in Drosophila simply by putting them in different environments for a number of generations. Eventually, when the two populations were put back together, the groups would not interbreed naturally, thus qualifying for allopatric speciation.
3. Lack of explanatory power
-The chicken-egg paradox is just Creation v. Evolution. No scientist will tell you a chicken popped out of nowhere. I don't understand it, you keep using speciation examples to try and disprove speciation. The bottleneck effect is explained by simply allele frequency because it is just a random event resulting in a dramatic shift of allele frequencies, if we are referring to the same thing. The Cambrian Explosion is also not a satifactory example. For all we know there was great biodiversity before the explosion, but those organisms did not secrete the correct chemicals or have the correct conditions to leave fossils. Also, the Explosion is partly due to the fact that land, previously uninhabited, was suddenly an available ecological niche.
4. Un-falsification
- I can't say I understand this argument either. All you need to prove that allele frequency is not enough to create the current biodiversity is to provide counter-examples, as you have done. Also, with simple organisms with fast breeding rates, you can change environments and try to use RMNS to predict what kind of speciation would occur if only allele frequency change was present.
5. Too complicated
-You are aware that the bottleneck effect is classified as genetic drift, yes? Also, you are using the old Creationist technique. "It's real complicated, so it can't be true."
In short, you seem to be confusing part of Neo-Darwinism with the whole. Even the speciation methods you mentioned include non RMNS examples (such as the polyploidy in plants, mechanical speciation). I'd also like to point out that you are also assuming a major conspiracy. The examples you provided are quite evident to most scientists. Isn't it a tad foolish to assume that no Neo-Darwinist ever heard of Polyploidy or the Bottleneck effect?

This message is a reply to:
 Message 1 by Jianyi Zhang, posted 04-26-2005 11:57 AM Jianyi Zhang has not replied

Replies to this message:
 Message 231 by Wounded King, posted 05-20-2005 4:18 AM wnope has replied

mick
Member (Idle past 4986 days)
Posts: 913
Joined: 02-17-2005


Message 222 of 305 (209497)
05-18-2005 8:17 PM
Reply to: Message 219 by Jianyi Zhang
05-13-2005 4:36 PM


hybridization
Jianyi writes:
The MISTWGM does not have to incest, they can mate with parental species, however, there is no healthy offspring, or no offspring at all, as they are different biological species. They only can have healthy offspring by mating among themselve.
This is a very bad description of hybridization in birds, which can hybridize readily and produce fertile or semi-fertile offspring.
how does your theory account for the widespread hybridization we find in nature?
Cheers
Mick

This message is a reply to:
 Message 219 by Jianyi Zhang, posted 05-13-2005 4:36 PM Jianyi Zhang has replied

Replies to this message:
 Message 226 by Jianyi Zhang, posted 05-19-2005 11:59 PM mick has not replied

EZscience
Member (Idle past 5154 days)
Posts: 961
From: A wheatfield in Kansas
Joined: 04-14-2005


Message 223 of 305 (209520)
05-18-2005 9:50 PM
Reply to: Message 220 by Wounded King
05-17-2005 5:25 AM


Re: circling
WK writes:
...poorer still if they occur in a animal which tends to avoid incest.
Which I would contend is > 90 % of outcrossing species.
The only animal species that benefit from inbreeding are those with Hamiltonian, as opposed to Fisherian, sex ratios.
That is to say, species such as gregarious parasitoids that have evolved in circumstances where sib-mating is the norm, rather than the exception. In these cases, female parasitoids search for rare hosts that, once encountered, are used to produce a large clutch / litter of offspring. Upon emergence, opportunities to mate with anyone other than a sib are slim to none.
The interesting thing is, the sex ratio becomes distorted drastically in favor of females in these situations.
Thus, conventional evolutionary theory would predict that 'if' sib-mating were in any way a significant contributor to population structure in a species, one would observe female-biased sex ratios.
This occurs because, as Hamilton pointed out in the 1980's (I can produce the exact reference if you insist), once sib-mating is without significant physiological cost (i.e. inbreeding depression), then females are favored who produce predominantly daughters, since these provide the biggest fitness 'payoff' to mothers - they are the ones that go out and parasitize hosts (or otherwise 'produce offspring') as opposed to sons, whose fitness is only determined by their mating success, which is much more of a 'crap shoot'.
Males are expendable. If they are only going to mate their sisters of the same clutch with any probability, their mother is better off (evolutionarily) producing one or two sons to mate 30-40 daughters, or the absolute minimum required to ensure all her daughters get mated. This leads to the strongly female-biased sex ratios observed in hymenopterous (wasp) parasitoids that are gregarious (large clutches of offspring emerge from a single parasitized host).
However, this strategy is not impervious to invasion by 'Fisherian Females'
The only way this strategy 'pays off' for the mother is IF her sons are the only ones mating her daughters.
If the sons of other females make a timely appearance, her skewed-offspring-sex-ratio strategy will fail because unrelated males will mate her daughters, and their mothers will exceed her in fitness. Under these situations, the sex ratio rapidly reverts to a Fisherian one, i.e. one-to-one.
In summary, it would be very difficult to demonstrate a significant role for inbreeding in the evolution of higher organisms without accounting for distorted sex ratios.
Now Zhang might argue that these 'super twinning events' are of low probability, but with huge contingent consequences when they do occasionally happen, and we could not rule that possibility offhand. However, I think that WK and I would both agree that old Zhang here bears the burden of evidence, evidence he has yet to produce.

This message is a reply to:
 Message 220 by Wounded King, posted 05-17-2005 5:25 AM Wounded King has not replied

Limbo
Inactive Member


Message 224 of 305 (209551)
05-19-2005 1:02 AM


Stopping Evolution?
Please don't reply to this off-topic message--AdminBen
You can reply in the appropriate thread here.
I saw this science daily article, and I was wondering if anyone wanted to speculate on the implications.
http://www.sciencedaily.com/...ases/2005/05/050518175350.htm
quote:
This research raises fundamental questions about evolution. Biologists have often thought about evolution in the same way many think about death and taxes -- something inevitable. But Romesberg is a chemist, and he found himself asking not only how, but why evolution happens.
Are mutations as random as we thought? Maybe mutations are controlled by a program. If so, how could we have evolved the program in the first place?
quote:
This brought Romesberg to the conclusion that mutation is a programmed stress response -- a survival mechanism.
This message has been edited by AdminBen, Thursday, 2005/05/19 03:14 PM
This message has been edited by AdminBen, Thursday, 2005/05/19 03:38 PM

Replies to this message:
 Message 225 by AdminBen, posted 05-19-2005 1:12 AM Limbo has not replied

AdminBen
Inactive Member


Message 225 of 305 (209552)
05-19-2005 1:12 AM
Reply to: Message 224 by Limbo
05-19-2005 1:02 AM


Re: Stopping Evolution?
Those who know better, correct me if I'm wrong, but...
This does not look related to this topic at all, save for the title. It's an interesting article, but doesn't belong here. I suggest you search for an appropriate thread (surely read the opening post, don't judge by the title).
One possibility is in the thread called "Random mutations." However, if you're interested only in how this relates to an ID hypothesis, then you may want to take it to one of the "evidence for ID" threads. If you do so, however, please make sure you understand the article well enough to argue the point first.
Please try and be more careful when trying to add new content (rather than replying to a post) to a thread. In general, titles around ehre are not clear enough to judge the topic of the thread (sorry about that). You really need to read over the OP for a thread in order to know if your new content belongs in the existing thread.
Thanks.
P.S. Interesting article. I'm looking forward to hearing discussion about it.
This message has been edited by AdminBen, Thursday, 2005/05/19 03:30 PM

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