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Hellbent

Against Neo-Darwinism

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I am taking a class called Environmental Evolution, but it's all about the Gaia hypothesis. Wikipedia's definition isn't entirely accurate, but gives a general idea of the hypothesis. According to James Lovelock, the founder of the hypothesis, it states that life interacts with and alters the environment towards a homeorhetic state suitable for life, not a homeostasis one, the difference being that life interacting and affecting the environment cannot control the environmental conditions to such a definitive stasis.

The professor of the class, Lynn Margulis is a strong proponent of this theory, and an eminent scientist in her field, and founder of the theory of Endosymbiosis and Symbiogenesis, which states, in part (in her words): "nucleated cells in general are co-evolved, integrated, microbial communities, rather than bacteria that simply got large by random mutation." She shares similar feelings as I do on Neo-Darwinism and so I was thinking of maybe doing my final presentation on the fundamental problems with Neo-Darwinism. As I understand it, the main gist of the theory is that evolution is driven by chance benefits from blind mutations.

I am posting to ask if anyone here is good at Statistics. The problem I see with Neo-Darwinism is that life is too incredibly complex, intricate, and delicate in its interrelationships for random, blind mutations to be responsible for speciation. The probability that random mutations would be able to produce beneficial traits and changes in organisms since the beginning of organismal evolution and lead to the kinds of complex interrelationships etc.found in Rainforests etc. is about as likely as someone taking various jars of paint and blindly (literally, with a blindfold on) trying random different approaches to painting a canvas in the hope of painting a non-abstract masterpiece. No matter how many times you try this, it's just never gonna happen, let alone painting something that is highly recognizable as something occurring commonly in the world. The confines of, or the narrowness of, how specific that painting needs to be is so minute (narrow) that no amount of time or attempts would ever yield a work of singular beauty. I'm looking for an analogy in the study of statistics that proves, or at least indicates, that you will never get certain results no matter how many times you try. A simple example in statistics is if you roll a six sided die 10,000 times, no matter how many times (infinite) that you roll that die 10,000 times, you'll never get the number 6 to show up one half of the time (the more times you roll it, the closer to 1/6th the time will the die show up), because of some law of probability. Can anyone help me come up with a better example in statistics that shows the problem with Neo-Darwinism's main tenant that states evolution, the formation of diverse species, happens through blind, chance, random mutations? Thanks! I would really appreciate any help in this regard.


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The "New Synthesis"
I am trying to find a good summary of this approach to evolution. If anyone knows anything about it or can recommend a good source, I'd appreciate it! I'm trying to find a summary of it specifically. All I know, I think I know.. heh, is that it relates to NeoDarwinism. Ernst Mayr and Julian Huxley apparently are proponents of this theory.

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No. You will find the question has been examined by those who are excellent at both statistics and biology. Evolution works out quite well as long as there are a sufficient number of mutations occurring, and to a certain extent even when there are not.

The pages you link don't describe anything that contradicts this except for the crap the crazier gaia proponents like to spout about everything being a giant living being. Things like endosymbiosis are so well accepted they make it into grade-10 biology classes.

Your analogy is as crap as the "blind watchmaker" one the fundies like. Natural selection isn't working towards a more perfect thing; it's just accruing changes to a species that don't kill it. That's key. The changes don't have to be good; they just have to not kill it. The ones that kill it usually go away and the ones that don't will stick around. They may help or hinder it later or they may not. They may even lead to curious symbiotic relationships that don't immediately show their benefit.

The reason the analogy sucks is because you don't get a succession of independent, random mutations. There will always be generations of them that can mate and pass on elements of themselves. If you paint a trillion random paintings (that's kind of numbers you can get with evolution) you might get some non-abstract stuff, but that still wouldn't be right. Something like painting 100 random paintings and then having a criteria for which ones get to pass on features to the next, but with random changes would be more accurate. There's a pretty kick-ass example with clocks on YouTube that shows this very, very well.

Positive adaptations have been observed with fairly complex life already. The clearest example is the colour change in moths living in London during the industrial revolution. There was a tendency for some of them to have black wings to start with. That wasn't common and was never a positive adaptation until coal-dust and soot-laden fog appeared. The black moth population completely out-competed the white moths when that happened. That didn't take very many generations.

Speciation probably requires isolated populations in most cases. Given that non-destructive random changes can happen often, species could diverge without either having a specific advantage for a given environment. They could even have identical environments. If we ever travel to the stars and lose some colonies I could see this happening with humans -- though it might take something like 100,000 years given how slowly humans reproduce and seeing as how that didn't happen with populations like the native Americans.

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That sums it up pretty well.

As far as statistics go the probability of the world evolving into the world we now live in with all that entails is now 1 to 1. Because it happened. Since evolution isn't working towards any specific goal, it doesn't matter what the outcome is, all that matters is that the lifeforms with good mutations will live to pas on their genes to the next. So any statistical improbabilities you can conjure up of how improbable it is that it evolved into this specific world we live in now, doesn't matter. It could only evolve into one world, and this is the one it happened to evolve into.

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You guys aren't helping me with my assignment, but, nonetheless, I appreciate your comments. I just want to make it really clear, tho, I'm not arguing intelligent design. I am arguing that evolution does not happen through random mutations per Neo-Darwinism. I want to show the problems in this theory. The air these posts have is that this totally non-controversial, yet science is changing all the time.... The scientist that came up with symbiogenesis, a theory she fought to get accepted by the mainstream, was seen as crackpot science when she first proposed it. It is now as accepted as the theory of evolution, and Neo-Darwinism, but she thinks Neo-Darwinism is bunk, but is not a creationist and is absolutely by no means arguing against evolution. So please, this is not a Creationism debate, it's a debate about the mechanisms of evolution. No one is arguing that evolution didn't occur, or that it didn't occur within the timeline of 4 billion years.

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The following are excerpts from a discussion among scientists from different parts of the world joined at Oxford to discuss Evolution. The symposium was titled "Homage To Darwin" (I think in honor of his 200th birthday) and was filmed in HD. Below are some excerpts. (voicesfromoxford.com) Direct link to part 2 of the three part series from which the below discusses.

Lynn Margulis: "I love Richard's metaphor of the selfish gene, because it focuses attention on the science behind natural history. But of course it's just a metaphor, because a gene doesn't have a self. A gene is not a self. How can something be selfish if it has no self? The self is the cell: all cells have self and the self has been forgotten; and even in hearts and livers the self has been forgotten: and this is my introduction to arguing the topology that's taught is not right. The idea that accumulation of random mutations is the way species change from one species to another has very little evidence for it. The junk DNA is just another way of saying we don't know what the DNA is doing. The unit of life on Earth is the cell; and there are two kinds of cells: bacteria-like cells and nucleated cells."

Later in the talk there was no consensus on what the phrase 'unit of selection' meant. Since Dawkins is the foremost expert, he was finally asked to give his definition.

Richard Dawkins: “There are two different definitions to the phrase 'Unit of selection': replicator and vehicle. The replicator is that which persists through time, and that is DNA or RNA or something like it. That is to say it coded information which is copied exactly, subject to occasional mutation. The vehicle is quite different. The vehicle might be a cell, it might be an individual, it is the unit which we observe in nature to survive or not survive, to reproduce or not reproduce. We observe Wildebeast—some of them die, some of them don't; we observe lions—some of them die, some of them don't. This is vehicle selection, that's what we actually see out there in nature, but the long term evolutionary consequence is the differential survival of replicators (DNA mostly) which exist inside those vehicles.” Dawkins: “From a field point of view it would be that which makes the difference between individuals.” I point this out because the whole point of the talk, of the scientists coming together, is that there are controversies about evolution and how it operates, even at its more fundamental levels.

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I agree that there were many possible outcomes of the evolution of life. We are just living in the one that came to be.

The gaia idea intrigues me. I'm no expert (everything I say here I just thought up myself and may have no use to you), but I had a quick thought that maybe gaia is similar to the conscious modern ideas of "helping the planet", like planting more trees to offset our negative impacts. In humans, we have intelligence and can see our effects on the biosphere, but other organisms don't have that ability.

So I was wondering if there is any part of an animal's instinct or an organism's genetic code that can regulate its behavior for the benefit of the environment. If a species acquires a trait that benefits it's reproduction in the short term, but is more detrimental in the long term because of disruption to other organisms and the surroundings, then that trait may not persist in the long term. So maybe mechanisms have arisen that promote stability of an organism's surroundings to allow the descendants of that organism to live to reproduce in the future.

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Hellbent said:

I just want to make it really clear, tho, I'm not arguing intelligent design.

I don't think anyone said you did. But your arguments echoes those of ID. I don't know much about this Gaia hypothesis, but there are things about your post that just fails.

Hellbent said:

no matter how many times (infinite) that you roll that die 10,000 times, you'll never get the number 6 to show up one half of the time

This really doesn't have anything to do with evolution.

Hellbent said:

the problem with Neo-Darwinism's main tenant that states evolution, the formation of diverse species, happens through blind, chance, random mutations?[/u]

This just makes me wonder if you understand evolution at all.
No, it doesn't go by blind chance. It forms through random mutations that are selected for by natural selection. This is NOT a random system.

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phi108 said:

I agree that there were many possible outcomes of the evolution of life. We are just living in the one that came to be.

The gaia idea intrigues me. I'm no expert (everything I say here I just thought up myself and may have no use to you), but I had a quick thought that maybe gaia is similar to the conscious modern ideas of "helping the planet", like planting more trees to offset our negative impacts. In humans, we have intelligence and can see our effects on the biosphere, but other organisms don't have that ability.

So I was wondering if there is any part of an animal's instinct or an organism's genetic code that can regulate its behavior for the benefit of the environment. If a species acquires a trait that benefits it's reproduction in the short term, but is more detrimental in the long term because of disruption to other organisms and the surroundings, then that trait may not persist in the long term. So maybe mechanisms have arisen that promote stability of an organism's surroundings to allow the descendants of that organism to live to reproduce in the future.

Very good! You basically understand the main principle of how Gaia works. I gave a presentation in class of examples of how micro-organisms in the oceans may play a part in regulating the geochemical makeup of the seas to be continually beneficial. The main part of my talk went something like this:

According to Mike Whitfield, chemical oceanographer, ¾ of all elements are influenced by biological processes. Copper, Cobalt, Zinc, Manganese, Iron are found in the ocean in trace amounts. Conventional wisdom has always been that these metals are in trace amounts because their concentrations have been determined by the chemistry of the oceans and that life has evolved to fit the geochemistry in the oceans today. Gaia would state otherwise.

How can these metals be found in trace amounts when there is a constant influx of them from the mid ocean spreading and from river run off? One would expect that there would be a net accumulation in the oceans of these metals. But they are rapidly removed by the interaction with microorganisms. Transition metals such as copper are necessary as enzyme cofactors and need to be at a very precise amount in the oceans. If the amounts are too high then they become poisonous, too low and they cannot perform their enzymatic function in the microorganisms. So in the present scientific mindset, life adapted to the trace concentrations found in the oceans, and, inexplicably, the levels have remained just so to continue to be suitable for those organisms.

However, there is evidence that the amounts of these trace metals are being regulated by microorganisms, which would explain the paradox of those trace metals occurring in such small amounts despite the continual influx of those metals. As an analogue to the process happening in the see, there was a high amount of phosphate introduced into Lake Erie and as a result there were massive blooms of algae. The blooms were possible because the algae used the phosphate to grow. Through the algae's process of using the phosphate to grow, the phosphate was then 'pooped' out in a form that allowed it to sink to the bottom and become buried in the sediments, and thus effectively removed from the lake. A similar scenario unfolded in Oneida Lake in upstate NY. There was a high input of manganese into Oneida Lake. As the manganese concentrations went up, it limited the growth of many organisms. But tended to stimulate the growth of manganese oxidizing bacteria. The result was great blooms of manganese oxidizing bacteria appeared in the lake which kept the level of manganese down to a relatively “normal” level.

Similar biological processes among other kinds of photosynthetic microorganisms (plankton) in the light penetrating area of the oceans (called the Photic Zone) provide examples of inorganic carbon being turned into organic carbon through photosynthesis. As these organisms grow they incorporate the trace metals into their internal biochemistry and into their hard parts. They pass through the food chain and get rained out in the waste product of larger organisms higher up in the food chain as poop. The result is 4-500 million tons of carbon rained down a year in the oceans. As the organisms or waste products decay, the trace metals are released into the deeps of the oceans where the ocean currents bring them back up to the surface in a different part of the world at a later date. And so the cycle continues thus regulating the trace metals.

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Hellbent said:

The problem I see with Neo-Darwinism is that life is too incredibly complex, intricate, and delicate in its interrelationships for random, blind mutations to be responsible for speciation.

Then what?
Random mutations have been observed. Many of them are discarded out of hands because they're not necessarily viable -- the outcome of random changes in a delicate mechanism. Just look at miscarriage statistics. If the result is still viable, however, then natural selection operates. If the mutation makes it so that the being is more likely to have many offsprings, the mutation is more likely to spread. It's pretty simple and not a logic that you can attack.

Hellbent said:

The probability that random mutations would be able to produce beneficial traits and changes in organisms since the beginning of organismal evolution and lead to the kinds of complex interrelationships etc.found in Rainforests etc. is about as likely as someone taking various jars of paint and blindly (literally, with a blindfold on) trying random different approaches to painting a canvas in the hope of painting a non-abstract masterpiece. No matter how many times you try this, it's just never gonna happen, let alone painting something that is highly recognizable as something occurring commonly in the world.

Actually, it is completely going to happen. I guarantee you.

Put on a mechanism for genetic transmission (i.e., you can create near-exact copies of your splashed paintings over and over and over again), and a mechanism for selection (the paintings that look the most like something not abstract are selected and get to have more near-exact copies made of them). Once you've got these two mechanisms in place, you're going to have non-abstract masterpieces pretty quickly; in just a few thousand generations.

Evolution works so well that it has been used deliberately, in simulation like that clock thing, for plenty of purposes. For example, in medical research, simulations are used to test molecules and alter them, selecting them against given criteria, and this is used to design new drugs.

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Wow, it's good to know I can actually think up something that makes sense!

So from what I can tell, the gaia hypothesis is sort of a way to explain beyond darwinian evolution? It seems to me like gaia mechanisms could evolve via natural selection, just over a long time, as opposed to the individual fitness and sucess/failure of a single organism's reproduction.

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kristus said:

This really doesn't have anything to do with evolution.

That's why it was a bad example. I was asking for a good one.

Gez said:

Then what?
Random mutations have been observed. Many of them are discarded out of hands because they're not necessarily viable -- the outcome of random changes in a delicate mechanism. Just look at miscarriage statistics. If the result is still viable, however, then natural selection operates. If the mutation makes it so that the being is more likely to have many offsprings, the mutation is more likely to spread. It's pretty simple and not a logic that you can attack.

[/b]

Lynn Margulis argues for symbiogensis as an alternative. She's not denying that there are mutations, but that they are not solely responsible (within natural selection etc) in speciation, and that symbiogensis is the primary mechanism (at least I think that's what she arguing). They argue about it part 3 of the talk: http://www.voicesfromoxford.com/homagedarwin_part3.html

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phi108 said:

Wow, it's good to know I can actually think up something that makes sense!

So from what I can tell, the gaia hypothesis is sort of a way to explain beyond darwinian evolution? It seems to me like gaia mechanisms could evolve via natural selection, just over a long time, as opposed to the individual fitness and success/failure of a single organism's reproduction.

Yeah, it works within evolution. I believe it deals more with organisms' inter-involvement with the environment, than how they evolve. It's looking at the bigger picture of how organisms affect their environment making it more suitable to them.

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Hellbent said:

Yeah, it works within evolution. I believe it deals more with organisms inter-involvement with the environment, than how they evolve. It's looking at the bigger picture of how organisms affect their environment making it more suitable to them.

Examples could include yeast in beer or wine, who affect their environment to make it eventually toxic to them. Or herbivores who overgraze their environment and turn it into a desert (happened with bunnies on several islands). Or, heck, humans (see the history of Easter Island).

Organisms don't affect their environment to make it more suitable to them. They affect their environment, period. If it makes it more suitable, great! They survive and spread. If it makes it less suitable, too bad. They die out.

And it's not just their environment. It can be a different environment. Cyanobacteria did not care what happened on the surface, since they lived in the seas. So them triggering the Oxygen Catastrophe was of no direct consequence to them; but it eradicated all surface lifeforms at the time.

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Gez said:

Organisms don't affect their environment to make it more suitable to them. They affect their environment, period.

It seems like if a species or community of species acquired behaviors that kept their environment suitable for their reproduction several generations down the line, these behaviors would increase long term fitness. I have no idea what real-world examples of this are. Hellbent says that ocean communities do this with trace metals.

Maybe a simple example is pollinators. Insects pollinate plants, ensuring that those plants will exist in the future, so that future geneartions of insects will survive on them. This involves the more immediate benefit of getting nectar from the plant, though. I don't really know if this example works, though.

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Gez said:

Examples could include yeast in beer or wine, who affect their environment to make it eventually toxic to them. Or herbivores who overgraze their environment and turn it into a desert (happened with bunnies on several islands). Or, heck, humans (see the history of Easter Island).

Organisms don't affect their environment to make it more suitable to them. They affect their environment, period. If it makes it more suitable, great! They survive and spread. If it makes it less suitable, too bad. They die out.

And it's not just their environment. It can be a different environment. Cyanobacteria did not care what happened on the surface, since they lived in the seas. So them triggering the Oxygen Catastrophe was of no direct consequence to them; but it eradicated all surface lifeforms at the time.

Can you elaborate on the surface catastrophe? In none of my classes has anyone mentioned the negative effects of the rise of oxygen. I only understood that it paved the way for the Cambrian Explosion. Were there organisms on land?

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It's silly to assume biologists are stuck in 19th-century view of the world where life doesn't affect the composition of the environment. You're saying her argument is that biologists are stuck thinking about the environment as they might have 100 years ago and this somehow shows evidence against natural selection. The citations on Wikipedia even indicate she doesn't say that!

The existence of an environment regulated by its inhabitants in no way begins to suggest an invalidation of natural selection or a mechanism to replace it. It's not even really talking about the same thing. Tjhe idea just adds another aspect to think about when considering the evolution of species in an ecosystem.

I wonder how one of those Daisyworld simulations would work out if the life involved instead evolved based on natural selection rather than having preset species that can never become totally extinct. I suspect in environments with limited diversity there would be a lot of cases of dead planets. Isaac Asimov addresses that in some of his fiction where he has human colony worlds exhibiting failed ecosystems on a regular basis, especially if abandoned, because the humans only brought the life they thought was immediately useful.

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Aliotroph? said:

You're saying her argument is that biologists are stuck thinking about the environment as they might have 100 years ago and this somehow shows evidence against natural selection. The citations on Wikipedia even indicate she doesn't say that!

Is she even against Natural Selection? As I understand it, she's against the modern synthesis, Natural Selection is certainly used in that. But it was already established by Darwin in his book the Origin of Life. I mean, that is pretty much the foundation for the theory of Evolution.

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kristus said:

Is she even against Natural Selection? As I understand it, she's against the modern synthesis, Natural Selection is certainly used in that. But it was already established by Darwin in his book the Origin of Life. I mean, that is pretty much the foundation for the theory of Evolution.

She's like symboigenesis to take most of the credit in place of random mutations. She is not arguing against the other factors and pressures working on evolution such as natural selection.

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Hellbent said:

Were there organisms on land?

It is thought there were; but they wouldn't have been developed enough to leave much in the way of fossils, what with being unicellular things.

We know there remain many anaerobic lifeforms, in certain specific environments (such as deep underground). Presumably, they would have existed on the surface as well.

It's also thought that before the oxigenation of the atmosphere, there was a methane greenhouse effect going on, with the Oxygen Catastrophe creating a glaciation by breaking that. There's not a lot of easy-access papers about that, but you may want to read this.

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Hellbent said:

As I understand it, the main gist of the theory is that evolution is driven by chance benefits from blind mutations.

You don't understand it.

Go away and study neo-Darwinism, probability and natural selection properly before asking for us to help with your assignment to impress you kook professor.

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Hellbent said:

She's like symboigenesis to take most of the credit in place of random mutations. She is not arguing against the other factors and pressures working on evolution such as natural selection.

If that were the case, then there wouldn't be problems with incorporating new species in a closed environment. Like rabbits in Australia. But there are, still to this day.

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phi108 said:
...
as opposed to the individual fitness and sucess/failure of a single organism's reproduction.

Evolution effects populations. Individuals don't evolve.

Hellbent said:
Yeah, it works within evolution. I believe it deals more with organisms' inter-involvement with the environment, than how they evolve. It's looking at the bigger picture of how organisms affect their environment making it more suitable to them.

Organisms are part of the environment. It's called an ecosystem.

kristus said:

But it was already established by Darwin in his book the Origin of Life. I mean, that is pretty much the foundation for the theory of Evolution.

Evolutionary theories had been around for quite some time before Darwin, but he was the first to propose the mechanism of 'natural selection' as the driving force behind it.

Obviously 150 years later, one who follows the modern day theory would realize they are missing two other major factors by saying people still accept Darwin's theory as complete, genetic drift, and sexual selection.

I'm not quite sure what this "neo-darwinism" is, because it sounds like a creationist attempt to portray people who accept the "modern synthesis" based on evidence as faith based followers.

Speciation has been witnessed, verified, repicated, and more. The fossil record, with it's nested hierarchies, derived characteristics, etc... have all been found to be congruent with modern day genetic analysis. Genetics are a second, independant, line of evidence for evolution.

People who deny evolution has occurred, is occurring, and will continue to do so are straight up delusional.

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E.J. said:

Evolutionary theories had been around for quite some time before Darwin, but he was the first to propose the mechanism of 'natural selection' as the driving force behind it.

Yes I am quite aware of that, but you shouldn't confuse Evolution theories with Theory of evolution.

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Why are you calling it "Neo-Darwinism", "Neo" means "New", as in all Fascist parties since the Italian PNF are technically "Neo Fascist". The random mutations and natural selection theory is the original Darwinism!

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Jonathan said:

Go away and study neo-Darwinism, probability and natural selection properly before asking for us to help with your assignment to impress you kook professor.

This. You aren't smarter than every biologist on the planet. The fact that you're talking about evolution as though it's a random process demonstrates your ignorance.

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