Long term lurker, rare poster, middling mental abilities. So please be gentle and if needed move this to a more appropriate subforum etc.

I should probably note that in addition to being just "average" when it comes to smarts, lately I've been dealing with post covid cognitive issues. As in I am struggling at times to carry a thought from one word to the next. So again I appreciate patience and whatever help anyone can lend to shed light on this for me. Typically I'd just keep searching and reading until I found what I want to know but the struggle is real right now...

For some reason on Facebook I've been getting sponsored ads from a group calling itself UNscientific. So far everything I've seen is just tired creationist nonsense like it would be silly to say cars evolve by themselves each year therefore evolution isn't true because reasons..... So not exactly top level arguments. For whatever reason of late I've been reading the comments... a bit out of boredom and a bit out of just wondering is anyone saying anything new? It's been several years at this point since I've brushed up on what the typical arguments are and how they are countered by reality in some way.

Anyway, I keep encountering commenters making claims that mendelian genetics are a barrier to evolution. I vaguely remember doing the squares in general biology in high school and can't remember anything from the two college level genetics courses I took online that would create issues for evolution. I'm really not even sure what it is they seem to be arguing other than because there are dominant and recessive genes that this somehow precludes evolution? I realize this is not a fantastic way of explaining an argument I'm running into and an even worse way to then ask "what the hell are they on about?" but I thought if anyone has seen this argument these forums would be the place to find out A) what is it they are trying to argue? and B) If there isn't an obvious counter can you give me a short explanation of why it is/isn't an issue. A couple of the comments seemed to focus on the inability of hybrids to reproduce as well. Which again I'm not sure how that precludes evolution in some way. I've asked a couple of them how this is a barrier and so far have not gotten coherent responses when I've gotten them at all. I should probably just forget about it but I'm seeing this way too frequently for them to not be getting this from somewhere. One of the typical offenders (DI/AIG/etc) has to have put this out at some point which I guess is what I'm counting on for you guys to have seen.

Thanks in advance for your time and help!

Unless they're willing to explain themselves it's just a bare assertion. No idea what they are trying to say.

It's their job to substantiate their claims, it's not anyone else's job to try to guess what they could be thinking of and then debunk their hypothetical thoughts.

The mode of the creationist shows scant regard for things like facts, evidence or honestly representing information. One of their main argumentative tactics involves promoting the idea that "science invalidates science" in some way.

With that in mind, one can imagine any number of creationist arguments around Mendel, such as:

a) scientists and biology teachers have always told us that evolution operates according to Mendel's strict model of generic inheritance.

b) since the 1970s scientists have understood that the deterministic Mendelian model of inheritance is not how DNA, genes, chromosome, and therefore evolution, actually works.

c) therefore everything you have heard or been taught about Mendel, and how his ideas are supposed to sit at the very foundation of evolution, is not just wrong, but an out-and-out lie.

d) therefore the only possible alternative explanation for life on Earth is 'god did it'.

Just guessing here though.

THWOTH wrote:The mode of the creationist shows scant regard for things like facts, evidence or an honestly representing information. One of their main argumentative tactics involves promoting the idea that "science invalidates science" in some way.

With that in mind, one can imagine any number of creationist arguments around Mendel, such as:

a) scientists and biology teachers have always told us that evolution operates according to Mendel's strict model of generic inheritance.

b) since the 1970s scientists have understood that the deterministic Mendelian model of inheritance is not how DNA, genes, chromosome, and therefore evolution, actually works.

c) therefore everything you have heard or been taught about Mendel, and how his ideas are supposed to sit at the very foundation of evolution, is not just wrong, but an out-and-out lie.

d) therefore the only possible alternative explanation for life on Earth is 'god did it'.

Just guessing here though.

Given my mental abilities right now I'm doing good to remember to come back and check the follow up messages here yet alone the genetics courses I took 10 or so years ago or high school biology some 25+ years ago. I know this would be a very simplified explanation but are b) and c) the case because the mendelian model doesn't account for the random nature of mutations and how they would impact DNA/genes/etc. and how they are selected? Don't feel obligated to spend an inordinate amount of time trying to explain if it's significantly more complex and you don't know of an easy resource to point me at for an explanation.

To be honest I don't really expect most of the creationists I run into to be able to articulate what it is they are arguing when more often than not they don't even really have a rudimentary understanding of what evolution includes/precludes. Typically I've found the folks here (and other similar forums) know the arguments the creationists are trying to make even if the creationist does not. So I thought it worth a shot asking here. I just had not seen this particular beast out in the wild before and encountered it 4-5 times across two threads in a short span of time. If I get a better grasp of what it is they seem to be getting at or a miracle occurs and they'll actually cite the argument for me I'll come back and possibly try again. I'm hopeful some of this cognitive fog I'm dealing with will eventually lift and maybe I can answer it for myself.

Thanks to both of you for your response.

collecemall wrote:

THWOTH wrote:The mode of the creationist shows scant regard for things like facts, evidence or an honestly representing information. One of their main argumentative tactics involves promoting the idea that "science invalidates science" in some way.

With that in mind, one can imagine any number of creationist arguments around Mendel, such as:

a) scientists and biology teachers have always told us that evolution operates according to Mendel's strict model of generic inheritance.

b) since the 1970s scientists have understood that the deterministic Mendelian model of inheritance is not how DNA, genes, chromosome, and therefore evolution, actually works.

c) therefore everything you have heard or been taught about Mendel, and how his ideas are supposed to sit at the very foundation of evolution, is not just wrong, but an out-and-out lie.

d) therefore the only possible alternative explanation for life on Earth is 'god did it'.

Just guessing here though.

Given my mental abilities right now I'm doing good to remember to come back and check the follow up messages here yet alone the genetics courses I took 10 or so years ago or high school biology some 25+ years ago. I know this would be a very simplified explanation but are b) and c) the case because the mendelian model doesn't account for the random nature of mutations and how they would impact DNA/genes/etc. and how they are selected? Don't feel obligated to spend an inordinate amount of time trying to explain if it's significantly more complex and you don't know of an easy resource to point me at for an explanation.

To be honest I don't really expect most of the creationists I run into to be able to articulate what it is they are arguing when more often than not they don't even really have a rudimentary understanding of what evolution includes/precludes. Typically I've found the folks here (and other similar forums) know the arguments the creationists are trying to make even if the creationist does not. So I thought it worth a shot asking here. I just had not seen this particular beast out in the wild before and encountered it 4-5 times across two threads in a short span of time. If I get a better grasp of what it is they seem to be getting at or a miracle occurs and they'll actually cite the argument for me I'll come back and possibly try again. I'm hopeful some of this cognitive fog I'm dealing with will eventually lift and maybe I can answer it for myself.

Thanks to both of you for your response.

I'd just say that b) and c) don't have to be true in that type of argument, because the creationist seeks to justify their beliefs regardless of the evidence. The motivation is to discredit empiricism, to cast doubt, to moralise, and to appear to 'win' in the eyes of their fellow travelers.

That said, the view of the gene as the primary causal agent of biology has undergone a bit of an overhaul in the last 30 years or so. This is an old essay but a pretty good springing off point: The Gene: A Needed Revolution, Craig Holdrege, 2005.

collecemall wrote:Long term lurker, rare poster, middling mental abilities. So please be gentle and if needed move this to a more appropriate subforum etc.

Gday mate - I recognize you from LoR.

collecemall wrote:Anyway, I keep encountering commenters making claims that mendelian genetics are a barrier to evolution. I vaguely remember doing the squares in general biology in high school and can't remember anything from the two college level genetics courses I took online that would create issues for evolution. I'm really not even sure what it is they seem to be arguing other than because there are dominant and recessive genes that this somehow precludes evolution? I realize this is not a fantastic way of explaining an argument I'm running into and an even worse way to then ask "what the hell are they on about?" but I thought if anyone has seen this argument these forums would be the place to find out A) what is it they are trying to argue? and B) If there isn't an obvious counter can you give me a short explanation of why it is/isn't an issue. A couple of the comments seemed to focus on the inability of hybrids to reproduce as well. Which again I'm not sure how that precludes evolution in some way. I've asked a couple of them how this is a barrier and so far have not gotten coherent responses when I've gotten them at all. I should probably just forget about it but I'm seeing this way too frequently for them to not be getting this from somewhere. One of the typical offenders (DI/AIG/etc) has to have put this out at some point which I guess is what I'm counting on for you guys to have seen.

I would simply dismiss this as an example of the endless litany of lies, misinformation and ignorance that is intrinsic to Creationism.

There is no reasonable way to regard any claim that Mendelian genetics is in conflict with any aspect of evolution as being honest. The modern evolutionary synthesis comprises Mendelian genetics at its foundation.

Of course, just as our knowledge of evolution has grown in the century plus it's been known, so our knowledge of genetics has grown dramatically, particularly in the last decade or so, and some of the details get more fuzzy and complex, like lateral gene transfer, but nothing obviates or challenges the fundamental fact of genetic variety, inheritance, and differential survival. It's all a con game with Creationists.

collecemall wrote:
... are b) and c) the case because the mendelian model doesn't account for the random nature of mutations and how they would impact DNA/genes/etc. and how they are selected?

Selection essentially has nothing to do with how variation arises, only whether that variation remains in the population or not, and to what degree it spreads in the population.

Mutations can arise from any number of sources, but the most basic and frequent way is copying errors at conception. But it doesn't matter whether the variation arises from cosmic rays or statistical shuffling, selection has no means of seeing or caring whence it arose, only in determining whether it remains.

We should note though that many mutations are not strictly 'random' either in that some genes are just more prone to mutate than other, and some are prone to mutate in a predictable way.

So yeah, it's all bullshit, and unsurprising bullshit at that - the natural environment of the anti-intellectual is in the disinformation spaces of social media.

I'll elaborate a little on what Spearthrower has presented above in his usual succinct manner.

Back in the 1970s, tropical fishkeepers specialising in the breeding of domesticated Betta splendens (Siamese Fighting Fish) found an unusual mutation appearing in their stocks - the Double Tail mutation.

Fish inheriting this mutation have two tails. Interestingly, the two tails in question are not arranged side by side, as is the case with domesticated Fantail or Veiltail Goldfish, but stacked vertically - what I refer to as an "over-under shotgun" arrangement). Each tail has its own caudal plate, and associated musculature.

Now it transpires that a single gene is implicated in this mutation, and that gene exhibits single-factor Mendelian recessive inheritance. But wait, it's also selectable, at least in the aquarium environment. Females are more powerfully attracted to Double Tail males than their single tail relations, and this can be demonstrated experimentally in the requisite setup. You'll find I've been fairly prolific with respect to discussing Double Tail Betta splendens here.

Note my caveat above, about this being selectable in the aquarium environment. I'll explain now in more detail.

In the wild, females of the species have relatively short fins, while males have somewhat longer fins (though nowhere near as long as in in aquarium bred specimens). There's a tradeoff - longer male finnage makes the males more attractive to females for mating purposes, but fins that are too long impede escape from predators to a potentially lethal extent. The wild environment therefore exhbiits two selection pressures - one arising from sexual selection, driving the emergence of longer male finnage, and the other from natural selection, curbing the extent of that male finnage extension.

In the aquarium, of course, threats from predators are removed. Consequently, mutants that would not survive in the wild, with the sort of enormously extended finnage seen in many aquarium specimens, can survive happily under human care, and breed. If you perform the requisite experiments, a female of the species, given a choice between several wild type males and aquarium bred males with much enhanced finnage, choose the aquarium males for mating. The more luxuriant the finnage, the greater the effect, and since Double Tail males have some of the most luxuriant finnage of all, they are powerfully sexually selectable in the aquarium.

Indeed, if those fish could survive in the wild, humans would not have needed to wait for mutants to appear in aquarium stocks, as natural forces would already have driven the appearance and preservation of those mutants in the wild. They would be the norm, not an exception restricted to the aquarium environment.

If you need another example to see this in action, look at Mexican Resplendent Quetzals (Pharomacrus mocinno). Males of this bird species have outlandish tail feathers, the appearance of which was driven by sexual selection on the part of the females. Females lack such ornamentation, and have tail feathers of more conventional length. Quite simply, any phenotype (and its underling genotype) will establish itself in a population if sufficient selection pressure exists to do so.

Possibly even more outrageous looking is the Long-Tailed Widowbird, Euplectes progne, which again exhibits tail feather elongation in males, and a fair amount of research has been published into the operation of sexual selection in this species. Perhaps the classic paper on this is the one documenting an experimental test of sexual selection in this species, viz:

Female Choice Selects For Extreme Tail Length In A Widowbird by Malte Andersson, Nature, 299: 818-820 (28th October 1982) [Paper can be found here, though sadly behind a paywall].

From that paper:

Andersson, 1982 wrote:
Darwin's1 bypothesis that male secondary sexual ornaments evolve through female preferences is theoretically plausible2-7, but there is little field experimental evidence that such preferences exist8-10. I have studied female mate choice in relation to male tail length in the Long-Tailed Widowbird, Euplectes progne, and report here that males in which the tail was experimentally elongated showed higher mating success than males having normal or reduced tail. The possibility that intrasexual competition among males maintains the long tail was not supported; males with shortened tails held their territories as long as did other males. These results suggest that the extreme tail length in Long-Tailed Widowbirds is maintained by female mating preferences.

Quite simply, the first port of call when dealing with creationist assertions, is the primary peer reviewed scientific literature, which invariably informs the honest reader that creationists are lying.

Oh, by the way, if you want an example of a test of sexual selection that you yourself can perform in your own home, try this from Ole Seehausen:

The Effect Of Male Colouration On Female Mate Choice In Closely Related Lake Victoria Cichlids (Haplochromis nyererei Complex) by Ole Seehausen and Jacques J. M. van Alphen, Behavioural Ecology & Sociobiology, 42: 1-8 (1998)

This is an experimental test that can be replicated by any competent tropical fishkeeper with half a dozen fish tanks and the requisite perseverance. I cover that paper in much more detail in this document. I think you'll find that document suitably informative.

Calilasseia wrote:I'll elaborate a little on what Spearthrower has presented above in his usual succinct manner.

Back in the 1970s, tropical fishkeepers specialising in the breeding of domesticated Betta splendens (Siamese Fighting Fish) found an unusual mutation appearing in their stocks - the Double Tail mutation.

Fish inheriting this mutation have two tails. Interestingly, the two tails in question are not arranged side by side, as is the case with domesticated Fantail or Veiltail Goldfish, but stacked vertically - what I refer to as an "over-under shotgun" arrangement). Each tail has its own caudal plate, and associated musculature.

Now it transpires that a single gene is implicated in this mutation, and that gene exhibits single-factor Mendelian recessive inheritance. But wait, it's also selectable, at least in the aquarium environment. Females are more powerfully attracted to Double Tail males than their single tail relations, and this can be demonstrated experimentally in the requisite setup. You'll find I've been fairly prolific with respect to discussing Double Tail Betta splendens here.

Note my caveat above, about this being selectable in the aquarium environment. I'll explain now in more detail.

In the wild, females of the species have relatively short fins, while males have somewhat longer fins (though nowhere near as long as in in aquarium bred specimens). There's a tradeoff - longer male finnage makes the males more attractive to females for mating purposes, but fins that are too long impede escape from predators to a potentially lethal extent. The wild environment therefore exhbiits two selection pressures - one arising from sexual selection, driving the emergence of longer male finnage, and the other from natural selection, curbing the extent of that male finnage extension.

In the aquarium, of course, threats from predators are removed. Consequently, mutants that would not survive in the wild, with the sort of enormously extended finnage seen in many aquarium specimens, can survive happily under human care, and breed. If you perform the requisite experiments, a female of the species, given a choice between several wild type males and aquarium bred males with much enhanced finnage, choose the aquarium males for mating. The more luxuriant the finnage, the greater the effect, and since Double Tail males have some of the most luxuriant finnage of all, they are powerfully sexually selectable in the aquarium.

Indeed, if those fish could survive in the wild, humans would not have needed to wait for mutants to appear in aquarium stocks, as natural forces would already have driven the appearance and preservation of those mutants in the wild. They would be the norm, not an exception restricted to the aquarium environment.

If you need another example to see this in action, look at Mexican Resplendent Quetzals (Pharomacrus mocinno). Males of this bird species have outlandish tail feathers, the appearance of which was driven by sexual selection on the part of the females. Females lack such ornamentation, and have tail feathers of more conventional length. Quite simply, any phenotype (and its underling genotype) will establish itself in a population if sufficient selection pressure exists to do so.

Possibly even more outrageous looking is the Long-Tailed Widowbird, Euplectes progne, which again exhibits tail feather elongation in males, and a fair amount of research has been published into the operation of sexual selection in this species. Perhaps the classic paper on this is the one documenting an experimental test of sexual selection in this species, viz:

Female Choice Selects For Extreme Tail Length In A Widowbird by Malte Andersson, Nature, 299: 818-820 (28th October 1982) [Paper can be found here, though sadly behind a paywall].

From that paper:

Andersson, 1982 wrote:
Darwin's1 bypothesis that male secondary sexual ornaments evolve through female preferences is theoretically plausible2-7, but there is little field experimental evidence that such preferences exist8-10. I have studied female mate choice in relation to male tail length in the Long-Tailed Widowbird, Euplectes progne, and report here that males in which the tail was experimentally elongated showed higher mating success than males having normal or reduced tail. The possibility that intrasexual competition among males maintains the long tail was not supported; males with shortened tails held their territories as long as did other males. These results suggest that the extreme tail length in Long-Tailed Widowbirds is maintained by female mating preferences.

Quite simply, the first port of call when dealing with creationist assertions, is the primary peer reviewed scientific literature, which invariably informs the honest reader that creationists are lying.

Oh, by the way, if you want an example of a test of sexual selection that you yourself can perform in your own home, try this from Ole Seehausen:

The Effect Of Male Colouration On Female Mate Choice In Closely Related Lake Victoria Cichlids (Haplochromis nyererei Complex) by Ole Seehausen and Jacques J. M. van Alphen, Behavioural Ecology & Sociobiology, 42: 1-8 (1998)

This is an experimental test that can be replicated by any competent tropical fishkeeper with half a dozen fish tanks and the requisite perseverance. I cover that paper in much more detail in this document. I think you'll find that document suitably informative.

I've always wondered; what is it about long tails that is so attractive? Does anyone know? Long tails seem almost ubiquitous in birds and fish!

There are two very closely related species of aquarium fish; the platy and the swordtail. Only the male swordtails have a longer tail, but female platies far prefer them to their own males, who have short tails, to the extent that I've been told that ALL platies in the aquarium trade are now platy/swordtail hybrids. So, female platies clearly have a preference for long tails, even though long tails don't occur in their own species.

Is the 'conspicuous handicap' hypothesis an adequate explanation for such a wide range of examples, and how could a preference evolve before the characteristic and the mutations for it?

fluttermoth wrote:
I've always wondered; what is it about long tails that is so attractive? Does anyone know? Long tails seem almost ubiquitous in birds and fish!

There could be as many different 'reasons' as there are species of fish and bird, but it's likely that the majority have a similar benefit.

fluttermoth wrote:There are two very closely related species of aquarium fish; the platy and the swordtail. Only the male swordtails have a longer tail, but female platies far prefer them to their own males, who have short tails, to the extent that I've been told that ALL platies in the aquarium trade are now platy/swordtail hybrids. So, female platies clearly have a preference for long tails, even though long tails don't occur in their own species.

fluttermoth wrote:Is the 'conspicuous handicap' hypothesis an adequate explanation for such a wide range of examples, and how could a preference evolve before the characteristic and the mutations for it?

I think it's an interesting hypothesis that may be true in some cases, but my guess for the most prominent reason is simply real estate. If flashing a bit of colour gets the ladies hot in the cheeks, then flashing a bit more of that colour makes the signal more likely to be received.

Oh, by the way, if you want an example of a test of sexual selection that you yourself can perform in your own home, ...

Such a fun way to start a sentence, and a sentence that could conclude in so many different ways!

Thanks again to everyone who responded. If I run across this again and can get more info I'll try to remember to come back. I think I generally understand why it shouldn't be an issue but I am still baffled why they think it pertinent. Anyway, thanks guys!

And as always, despite the absurd contrived dichotomy - even if all of evolution were somehow shown false, that wouldn't thereby make Creationism true by default. Creationism is unable to defend its own contentions, which is why it reads like one long ignorant and ill-informed attack on science and real-world evidence.

THWOTH wrote:The mode of the creationist shows scant regard for things like facts, evidence or honestly representing information.

[Reveal] Spoiler:

One of their main argumentative tactics involves promoting the idea that "science invalidates science" in some way.

With that in mind, one can imagine any number of creationist arguments around Mendel, such as:

a) scientists and biology teachers have always told us that evolution operates according to Mendel's strict model of generic inheritance.

b) since the 1970s scientists have understood that the deterministic Mendelian model of inheritance is not how DNA, genes, chromosome, and therefore evolution, actually works.

c) therefore everything you have heard or been taught about Mendel, and how his ideas are supposed to sit at the very foundation of evolution, is not just wrong, but an out-and-out lie.

d) therefore the only possible alternative explanation for life on Earth is 'god did it'.

Just guessing here though.

This is why it’s pointless to have the discussion with creationists. They get to simply lie, make shit up, while we are bound to facts.


Sent from my iPad using Tapatalk Pro

Spearthrower wrote:
I think it's an interesting hypothesis that may be true in some cases, but my guess for the most prominent reason is simply real estate. If flashing a bit of colour gets the ladies hot in the cheeks, then flashing a bit more of that colour makes the signal more likely to be received.

Backing up that idea, is the manner in which artificial enhancement of certain sensory cues can become a superstimulus. The enhanced male finnage in aquarium specimens of Betta splendens certainly qualifies in this respect.

In the case of platies and swordtails, life is rather interesting. Throughout Central America, there are numerous species in tne Genus Xiphophorus, some of which have long "swordtail" adornments in the males (X. hellerii being the one first domesticated), some with short adornments (X. montezumae springs to mind here) and some with no such adornment (X. maculatus and allies). Several of which can hybridise readily with each other, but the details of which combinations produce fertile offspring are complicated.

Indeed, this Genus once again illustrates that tidy categories have a habit of being of limited utility in biology. Although classified as distinct species, the members of that Genus are possibly best thought of as an incipient species complex.

That's the joke at the base of taxonomy that your average fundy will never appreciate.

Ultimately there is no such thing as a species.

It is a term of convenience used to allow comparisons between closely related populations which depends largely on context and the particular species concepts applied by various workers and the reach of the particular conversation being had. The needs of field biologists and cosetted researchers do not always coincide.

Pretty sure the fundy world is largely incapable of understanding such nuance.

Calilasseia wrote:
Indeed, this Genus once again illustrates that tidy categories have a habit of being of limited utility in biology. Although classified as distinct species, the members of that Genus are possibly best thought of as an incipient species complex.

Super useful - essential, really - to having any form of conversation about the differences between organisms, but the moment you start prodding at the label as depicting a distinct set of descriptions only applicable to an isolatable group, it all falls apart.

It falls apart at every level; through geographical space in the present where conspecific members have a suite of descriptions which only wholly apply to the archetype or a relatively minor subset; to the added dimension of ancestral time.

The Creationist 'challenge' of providing intermediaries, taken to its logical end, would require having a fossil of every single individual that ever lived. Never see them getting off their arses to find them, or you know, to provide *any* evidence for Creationism.

Fenrir wrote:Ultimately there is no such thing as a species.

There is such a thing as species, you just can't find it in the wild.

Incidentally, my son's science class book provides a simple, yet complete picture of how Mendellian genetic inheritance both permits and preserves the diversity that leads to adaptive evolution.

That's science for 10 year olds.

Creationism.

Spearthrower wrote:

Fenrir wrote:Ultimately there is no such thing as a species.

There is such a thing as species, you just can't find it in the wild.

Are you suggesting that clear seperation of 'kinds' can not be observed.
Astonishing. perhaps I have just jumped in mid way to something deep and meaningful .. do share.

Paul.