Best proofs of evolution

For the discussion of the sciences. Physics problems, chemistry equations, biology weirdness, it all goes here.

Moderators: gmalivuk, Moderators General, Prelates

PossibleSloth
Posts: 88
Joined: Mon May 11, 2009 6:51 am UTC
Location: Boston (or thereabouts)

Re: Best proofs of evolution

Postby PossibleSloth » Thu Apr 04, 2013 6:09 pm UTC

Technical Ben wrote:For example with the E coli. We confirmed it has enough chances for a single nucleotide mutation. What about the numbers for, as we admitted, the needed additional mutations? Dealing a single mutation is mundane, dealing 2 matching mutations requires more populations, variation and reproduction? So, do I have a requirement of matching 1 card in a dealt deck of cards, or matching 2 dealt deck of cards?

I think the problem is that you're treating the outcome as the only "correct" solution. The idea that evolution needed to create life exactly as it is today for life to occur is simply not true.There are any number of combinations of mutations which could produce similar phenotypic changes in an organism.

The other issue is that mutations are cumulative. Even if a certain SNP doesn't confer an advantage or disadvantage to an individual, it still gets passed on to descendants and becomes part of the population. Each generation inherits the mutations from its parents and adds its own. In fact, the big advantage of sexual reproduction (from an evolutionary point of view) is that it allows far more combinations of these acquired mutations, and therefore greatly increasing diversity.

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Best proofs of evolution

Postby Izawwlgood » Thu Apr 04, 2013 6:22 pm UTC

Technical Ben wrote:Ok. So what happens if the ideal mutation rate is not met? How comes life has met it?

Lack of diversity that may lead to extinction if a species doesn't adapt.
Not all life has met it; indeed, species that become extinct did not meet it. The life you see today is the life that adapted quickly enough.
I'm sure I'm going to muck something up here, so sorry in advance;
tomandlu wrote:I've always thought that variation rather than mutation provided most of the material that selection works with, but now I'm not even sure whether the distinction even exists. (I see variation as referring to the flexibility of the genome over a given range, whereas mutation implies a change to that range).


Variation is in reference to the diversity found within a given species. So, human males, lets say, if well fed, are between 5' and 6' tall. If a crazy spinning blade flew across the world every 10 years magically only cutting down anyone above 5'5, then in a handful of generations, you'd expect the average height to drop. Because people can't duck.
Mutation increases variation, and is the source of that variation.
If you have bottleneck events, wherein the total population drops to a small number and only select few individuals reproduce, then you develop a species with little variation, like cheetahs or human beings.
Variation, I think, refers to how much genetic diversity exists between two individuals of the same species.

tomandlu wrote:When it comes to a viable and useful mutation, what sort of physical scales are we going up to? Minor changes to chemical processes? New organs or similar? Organs with significant new or changed functionality? Something else?

I think it entirely depends, but generally speaking, broad dramatic changes are less likely to be viable. A SNP is unlikely to make me grow antennae, unless of course, antennae were ancestrally lost and selected for by a disruption caused by a SNP.

tomandlu wrote:My understanding of speciation is that is generally occurs due, initially, to isolation - two essentially identical populations, for one reason or another, no longer inter-breed even though they are capable of it, and, in time, further evolutionary divergence will generally render reproduction impossible. Likewise, I would have assumed that a mutation or change making inter-breeding impossible would follow rather than precipitate the initial isolation - how wrong is this view?

Remember the overwhelming majority of mutations are silent, and most of the rest are detrimental (varyingly detrimental at that). But yes, I think that view is fairly reasonable, as different selection pressures on the same species will select for different variances and allow for different mutations.
Don't forget though a lot of reproduction is behavioral; if you're a female bird and you're fucking nuts for blue footed males, a brown footed mutant male may not have any disadvantage in surviving, but might be the unsexiest thing in the world to you.

tomandlu wrote:When mutation does occur that does lead to the carrier being unable to interbreed with individuals not carrying the mutation, how does it not immediately die out? I can think of several plausible ways (including "you never get mutations like that"), but I'd be curious to hear some specifics.

It would immediately die out, and that sort of mutation would/has negatively impacted the fecundity of the individual. That said, mutations may gradually accumulate, may create recessive diseases, etc.
Last edited by Izawwlgood on Thu Apr 04, 2013 6:40 pm UTC, edited 1 time in total.
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26738
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Best proofs of evolution

Postby gmalivuk » Thu Apr 04, 2013 6:40 pm UTC

You could (in the sense that it's theoretically possible if not at all probable) also, for example, have a succession of two (are only two a "succession"?) mutations that lead to loss of interbreeding ability between two populations.

The first, where allele A becomes A', has no detrimental effect on its own, and perhaps conveys some benefits in certain situations, and eventually exists in a reasonably large portion of the population. Then a second mutation happens in one of the A' individuals, whereby B becomes B'. If B' individuals can't interbreed with A individuals, but have increased fecundity (or some other benefit) with A' individuals, then B' may not immediately vanish, but instead spread throughout the A' population until AB and A'B' could be considered separate species.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

qetzal
Posts: 861
Joined: Thu May 01, 2008 12:54 pm UTC

Re: Best proofs of evolution

Postby qetzal » Thu Apr 04, 2013 8:16 pm UTC

PossibleSloth wrote:The other issue is that mutations are cumulative. Even if a certain SNP doesn't confer an advantage or disadvantage to an individual, it still gets passed on to descendants and becomes part of the population. Each generation inherits the mutations from its parents and adds its own. In fact, the big advantage of sexual reproduction (from an evolutionary point of view) is that it allows far more combinations of these acquired mutations, and therefore greatly increasing diversity.


Indeed, IIRC Lenski's long-term E. coli study shows this very well. Evolving the ability to grow on citrate required at least two separate mutations. The first was apparently neutral by itself. Only after a second mutation could the cells use citrate. BUT, the second mutation only allowed citrate use if the first mutation was already present. Without the first mutation (which seems useless by itself), the second mutation gave no advantage.

User avatar
bouer
Posts: 262
Joined: Sat Jan 26, 2013 9:26 pm UTC

Re: Best proofs of evolution

Postby bouer » Fri Apr 05, 2013 2:59 am UTC

My favourite proof of evolution is:

If we accept that there is some variability of traits within species (undeniable)
And we accept that some of these traits are heritable (pretty much indisputable)
And we accept that some of these heritable, variable traits affect organisms chances of reproducing (also nearly indisputable)
And we accept more than 1 generation has passed (which everyone but Last Thursdayists do)
Then we accept evolution.

There is no logical way to accept the premises and reject the conclusion.

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Best proofs of evolution

Postby tomandlu » Fri Apr 05, 2013 6:04 am UTC

bouer wrote:My favourite proof of evolution is:

If we accept that there is some variability of traits within species (undeniable)
And we accept that some of these traits are heritable (pretty much indisputable)
And we accept that some of these heritable, variable traits affect organisms chances of reproducing (also nearly indisputable)
And we accept more than 1 generation has passed (which everyone but Last Thursdayists do)
Then we accept evolution.

There is no logical way to accept the premises and reject the conclusion.


Creationists/ID proponents will accept minor changes (because they have to), but reject speciation (because they can).
How can I think my way out of the problem when the problem is the way I think?

User avatar
yurell
Posts: 2924
Joined: Sat Nov 13, 2010 2:19 am UTC
Location: Australia!

Re: Best proofs of evolution

Postby yurell » Fri Apr 05, 2013 6:18 am UTC

tomandlu wrote:Creationists/ID proponents will accept minor changes (because they have to), but reject speciation (because they can).


Some of them accept speciation (e.g. Kent Hovind), but reject that it can cause the creation of new 'kind's (for suitably ambiguous definitions of the word).
cemper93 wrote:Dude, I just presented an elaborate multiple fraction in Comic Sans. Who are you to question me?


Pronouns: Feminine pronouns please!

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Best proofs of evolution

Postby tomandlu » Fri Apr 05, 2013 7:06 am UTC

yurell wrote:
tomandlu wrote:Creationists/ID proponents will accept minor changes (because they have to), but reject speciation (because they can).


Some of them accept speciation (e.g. Kent Hovind), but reject that it can cause the creation of new 'kind's (for suitably ambiguous definitions of the word).


Indeed. The logical contortions would make a yoga master jealous. The bottom line is that they will probably accept anything that doesn't require all modern apes to have a common ancestor. Can't think why...
How can I think my way out of the problem when the problem is the way I think?

User avatar
PolakoVoador
Posts: 1028
Joined: Fri Jun 10, 2011 11:11 pm UTC
Location: Brazil

Re: Best proofs of evolution

Postby PolakoVoador » Fri Apr 05, 2013 2:39 pm UTC

tomandlu wrote:
yurell wrote:
tomandlu wrote:Creationists/ID proponents will accept minor changes (because they have to), but reject speciation (because they can).


Some of them accept speciation (e.g. Kent Hovind), but reject that it can cause the creation of new 'kind's (for suitably ambiguous definitions of the word).


Indeed. The logical contortions would make a yoga master jealous. The bottom line is that they will probably accept anything that doesn't require all modern apes to have a common ancestor. Can't think why...


Because that would make us all just marginally smarter monkeys apes, and you can guess some implications of this...


PS.: in Portuguese we don't have two words for monkey/apes, only "macaco" which I usually translate to "monkey" because it sounds funnier :P

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Best proofs of evolution

Postby tomandlu » Fri Apr 05, 2013 4:13 pm UTC

PolakoVoador wrote:
tomandlu wrote:The bottom line is that they will probably accept anything that doesn't require all modern apes to have a common ancestor. Can't think why...


Because that would make us all just marginally smarter monkeys apes, and you can guess some implications of this...

PS.: in Portuguese we don't have two words for monkey/apes, only "macaco" which I usually translate to "monkey" because it sounds funnier :P


That's interesting - I'd always understood that taxonomic distinctions were fairly consistent across all cultures.

BTW I'm British, so "Can't think why?" generally means "Yes I can".
How can I think my way out of the problem when the problem is the way I think?

Technical Ben
Posts: 2986
Joined: Tue May 27, 2008 10:42 pm UTC

Re: Best proofs of evolution

Postby Technical Ben » Fri Apr 05, 2013 6:36 pm UTC

ahammel wrote:
Technical Ben wrote:Ok. So what happens if the ideal mutation rate is not met?
Extinction.


Thanks. So do I assume the ideal mutation rate is met? How do I confirm the lack of extinction of one species is due to adaptation, mutation and evolution, and the extinction of another is due to it's inability to adapt? I can see that the dinosaurs did not grow asteroid repelling armor (to take it to an extreme). How do I confirm those that did survive are "adapting" and not just "the pre-existing "outliners" of the sample? How do I confirm the mutations are "new" and not already in the population? Or that the mutation did not exist in the past?

You really need to let go of the idea that these 'examples' have anything to do with natural selection.

Sorry, if they do not, can I use them for the scale of the numbers involved? A 1.5mb floppy with random data is still something I can select for. Even if it's a bit obtuse for me to play the part of the "environment" and a magnet to play the part of mutations. I can perform natural selection and mutation on such an example, right? I can apply a genotype and phenotype to it? Or does it need to be something more physical, like a bag of cogs for making a watch?

Possibly in some cases. In which case the cure would be to learn that natural selection is decidedly non-random.

Thanks. Which is where we are making progress here. I know that natural selection is not a random process, hence we have to apply limits to it. Is it wrong to learn what it is limited by? To learn where it cannot provide answers (at this time, or at all if covered by other theories or subjects)?

What might 'survive temp' be?

If you continue to make up terms, we will continue to not know what they mean.

If an animal survives an environment, or dies from the environment. For example the environments temperature, as you suggested. Is the survival caused by it's genotype or by other circumstances? Is it caused by variation in it's genotype, or by variation by other factors (food available when it was younger, learned reflexes etc)? How do I filter out these effects to confirm I'm observing correlation with mutations?

This thought experiment has nothing whatever to do with genotypes, phenotypes, natural selection or evolution, so far as I can see. There's no analog of reproduction or mutation

Ok, so if I flip a coin, it's not similar to a spread of probability of a mutation? If I choose to keep or replicate the coins that meet a requirement, that's not similar to keeping and reproducing a population that meets and environment?

What? Where did you get the idea that natural selection requires independent, identical mutations in different organisms?

Sorry, I did not mean 2 packs of cards for 2 different organisms, but that getting a "match" in some circumstances is a very low probability. The probability of 1 mutation is rather high. The probability of 1 mutation followed by a second gives diminishing probabilities, does it not?

PossibleSloth wrote:I think the problem is that you're treating the outcome as the only "correct" solution. The idea that evolution needed to create life exactly as it is today for life to occur is simply not true.There are any number of combinations of mutations which could produce similar phenotypic changes in an organism.

The other issue is that mutations are cumulative. Even if a certain SNP doesn't confer an advantage or disadvantage to an individual, it still gets passed on to descendants and becomes part of the population. Each generation inherits the mutations from its parents and adds its own. In fact, the big advantage of sexual reproduction (from an evolutionary point of view) is that it allows far more combinations of these acquired mutations, and therefore greatly increasing diversity.

Thanks. It's that I am not sure how I can assume either way. So, how do I know it's accumulative and not a "correct (low probability hit)" result I need? I can deal a "snap" in cards easy. I cannot deal an entire deck of "snap" cards though. How do I confirm that the mutation are additive and incremental? For example, I cannot select from the noise on an untuned TV set for those that are "closer" to a football game. I can if I select each pixel at a time and wait for the next to match. So, how do I confirm the environment has enough selective pressure, and the mutation enough of a "signal (effect on phenotype)" to cause a change in the population?

Basically, if I sit in a card game and someone deals out 2 packs of matching cards, I'm a fool to believe they did so by "chance". If they say "I dealt the cards out randomly", but they selected each card sequentially via a rule of letting the matching cards survive, and dealing new cards each mismatch, I'm a fool to believe it was "chance". Both deal out random cards, both deal 2 matching decks (here the life and the environment). Neither match my understanding of "chance occurrence". Is that right?
Last edited by Technical Ben on Fri Apr 05, 2013 6:44 pm UTC, edited 1 time in total.
It's all physics and stamp collecting.
It's not a particle or a wave. It's just an exchange.

speising
Posts: 2350
Joined: Mon Sep 03, 2012 4:54 pm UTC
Location: wien

Re: Best proofs of evolution

Postby speising » Fri Apr 05, 2013 6:42 pm UTC

Technical Ben wrote:
ahammel wrote:
Technical Ben wrote:Ok. So what happens if the ideal mutation rate is not met?
Extinction.


Thanks. So do I assume the ideal mutation rate is met? How do I confirm the lack of extinction of one species is due to adaptation, mutation and evolution, and the extinction of another is due to it's inability to adapt? I can see that the dinosaurs did not grow asteroid repelling armor (to take it to an extreme). How do I confirm those that did survive are "adapting" and not just "the pre-existing "outliners" of the sample? How do I confirm the mutations are "new" and not already in the population? Or that the mutation did not exist in the past?


of course the survivors are the outliers. thats the "selection" part. the outliers were created by mutation/variation.

screen317
Posts: 252
Joined: Mon May 16, 2011 7:46 pm UTC

Re: Best proofs of evolution

Postby screen317 » Fri Apr 05, 2013 6:49 pm UTC

Technical Ben wrote:Thanks. So do I assume the ideal mutation rate is met?
This doesn't mean anything since different organisms have different mutation rates.

How do I confirm the lack of extinction of one species is due to adaptation, mutation and evolution, and the extinction of another is due to it's inability to adapt? I can see that the dinosaurs did not grow asteroid repelling armor (to take it to an extreme). How do I confirm those that did survive are "adapting" and not just "the pre-existing "outliners" of the sample? How do I confirm the mutations are "new" and not already in the population? Or that the mutation did not exist in the past?
Mutations often happen regardless of stimuli. There is an intrinsic inability for DNA (or RNA) to replicate perfectly. Also, the "dinosaur extinction" was not due directly to them getting hit by the asteroid itself.

Sorry, if they do not, can I use them for the scale of the numbers involved? A 1.5mb floppy with random data is still something I can select for. Even if it's a bit obtuse for me to play the part of the "environment" and a magnet to play the part of mutations. I can perform natural selection and mutation on such an example, right? I can apply a genotype and phenotype to it? Or does it need to be something more physical, like a bag of cogs for making a watch?
You don't seem to know what genotype and phenotype mean.

Thanks. Which is where we are making progress here. I know that natural selection is not a random process, hence we have to apply limits to it. Is it wrong to learn what it is limited by? To learn where it cannot provide answers (at this time, or at all if covered by other theories or subjects)?
Please use less verbose language. This makes almost no sense.

If an animal survives an environment, or dies from the environment. For example the environments temperature, as you suggested. Is the survival caused by it's genotype or by other circumstances? Is it caused by variation in it's genotype, or by variation by other factors (food available when it was younger, learned reflexes etc)? How do I filter out these effects to confirm I'm observing correlation with mutations?
Is the trait heritable? That's the difference.

Ok, so if I flip a coin, it's not similar to a spread of probability of a mutation? If I choose to keep or replicate the coins that meet a requirement, that's not similar to keeping and reproducing a population that meets and environment?
What does "keep or replicate the coins" mean??? Can you use a real world example?

Sorry, I did not mean 2 packs of cards for 2 different organisms, but that getting a "match" in some circumstances is a very low probability. The probability of 1 mutation is rather high. The probability of 1 mutation followed by a second gives diminishing probabilities, does it not?
No idea what you mean.


Thanks. It's that I am not sure how I can assume either way. So, how do I know it's accumulative and not a "correct (low probability hit)" result I need? I can deal a "snap" in cards easy. I cannot deal an entire deck of "snap" cards though. How do I confirm that the mutation are additive and incremental? For example, I cannot select from the noise on an untuned TV set for those that are "closer" to a football game. I can if I select each pixel at a time and wait for the next to match. So, how do I confirm the environment has enough selective pressure, and the mutation enough of a "signal (effect on phenotype)" to cause a change in the population?
Also no idea what you mean.


Try using less words to say what you mean.

Technical Ben
Posts: 2986
Joined: Tue May 27, 2008 10:42 pm UTC

Re: Best proofs of evolution

Postby Technical Ben » Fri Apr 05, 2013 6:54 pm UTC

Thanks. I can confirm in the past that survivors were outliners. How do I confirm that survivors in the past were 1) hereditary and 2) mutations?
It's all physics and stamp collecting.
It's not a particle or a wave. It's just an exchange.

screen317
Posts: 252
Joined: Mon May 16, 2011 7:46 pm UTC

Re: Best proofs of evolution

Postby screen317 » Fri Apr 05, 2013 6:58 pm UTC

Technical Ben wrote:Thanks. I can confirm in the past that survivors were outliners. How do I confirm that survivors in the past were 1) hereditary and 2) mutations?
Survivors "aren't" any of those things. They had mutations that were beneficial to reproduction in some way and passed those on as a result of being more successful.

Technical Ben
Posts: 2986
Joined: Tue May 27, 2008 10:42 pm UTC

Re: Best proofs of evolution

Postby Technical Ben » Fri Apr 05, 2013 7:08 pm UTC

How do I confirm their parents had 1) a mutation 2) a mutation that was passed on by inheritance? I can do this for current observations and living things. How do we apply it to now extinct animals? Are they not already extinct?

I can observe this in the current animals to the current extent available. How do I confirm that that can be scaled further if I cannot observe the gradual changes on longer scales?

As a simple real life example. E-coli and fruit flies. We have already been given the example of additive mutations in E-coli. Can I make the assumption that if I do the same with fruit flies, that mutations scale to new functionality in them? Can I assume, or observe, that fruit flies would attain photoluminescence or something if selected for?
It's all physics and stamp collecting.
It's not a particle or a wave. It's just an exchange.

screen317
Posts: 252
Joined: Mon May 16, 2011 7:46 pm UTC

Re: Best proofs of evolution

Postby screen317 » Fri Apr 05, 2013 7:11 pm UTC

Technical Ben wrote:How do I confirm their parents had 1) a mutation 2) a mutation that was passed on by inheritance? I can do this for current observations and living things. How do we apply it to now extinct animals? Are they not already extinct?

I can observe this in the current animals to the current extent available. How do I confirm that that can be scaled further if I cannot observe the gradual changes on longer scales?

As a simple real life example. E-coli and fruit flies. We have already been given the example of additive mutations in E-coli. Can I make the assumption that if I do the same with fruit flies, that mutations scale to new functionality in them? Can I assume, or observe, that fruit flies would attain photoluminescence or something if selected for?

We have been able to extract DNA from fossils of extinct species, though that is not always reliable. You sequence the DNA. What other way is a mutation passed on than inheritance??


You don't appear to understand what photoluminescence means:
http://en.wikipedia.org/wiki/Photoluminescence

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Best proofs of evolution

Postby Izawwlgood » Fri Apr 05, 2013 7:12 pm UTC

Ben, I think it would be really helpful for your own understanding if you stopped trying to force these poor fitting analogies into your concept of evolution, and instead started listening to the replies explaining your miscommunications.

Technical Ben wrote:So do I assume the ideal mutation rate is met? How do I confirm the lack of extinction of one species is due to adaptation, mutation and evolution, and the extinction of another is due to it's inability to adapt?

You asking this indicates you haven't been listening; adaptation is a process mediated by pressures selecting for traits which are produced by mutations and variation.

Extinction is caused when an organism cannot adapt to the pressures. Selection pressures are such because they change the reproductive potential of an individual; for example, if an organism survives best in 80 degree water, and suddenly finds itself in 60 degree water, what do you think will happen to it, and more importantly, what do you think will happen to subsequent generations of this organism if they remain in 60 degree waters?

Technical Ben wrote:How do I confirm their parents had 1) a mutation 2) a mutation that was passed on by inheritance? I can do this for current observations and living things. How do we apply it to now extinct animals? Are they not already extinct?

This has already been answered; not all mutations are heritable, so, the way you can confirm if a particular mutation is heritable is if it is found in a single pedigree. I.e., if a mutation is found in a given animal and is a heritable mutation, you will expect to find it in passed on in lineages. If it is a spontaneous mutation, you will find it occurring randomly.
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

User avatar
PolakoVoador
Posts: 1028
Joined: Fri Jun 10, 2011 11:11 pm UTC
Location: Brazil

Re: Best proofs of evolution

Postby PolakoVoador » Fri Apr 05, 2013 7:16 pm UTC

Technical Ben wrote:How do I confirm their parents had 1) a mutation 2) a mutation that was passed on by inheritance? I can do this for current observations and living things. How do we apply it to now extinct animals? Are they not already extinct?

I can observe this in the current animals to the current extent available. How do I confirm that that can be scaled further if I cannot observe the gradual changes on longer scales?

Yes you can. You know, fossil records are a thing. For example, evolution of mammalian auditory ossicles:

Wikipedia wrote:The evolution of mammalian auditory ossicles is one of the most well-documented[1] and important evolutionary events, demonstrating both numerous transitional forms as well as an excellent example of exaptation, the re-purposing of existing structures during evolution.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26738
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Best proofs of evolution

Postby gmalivuk » Fri Apr 05, 2013 7:29 pm UTC

Technical Ben wrote:As a simple real life example. E-coli and fruit flies. We have already been given the example of additive mutations in E-coli. Can I make the assumption that if I do the same with fruit flies, that mutations scale to new functionality in them?
Yes. Even if we had never observed the effects of mutations in fruit flies, that would be by far the most parsimonious explanation imaginable.

The alternative is that there is something that somehow prevents additive mutations in fruit flies from having any effects on phenotype, which is a rather extraordinary claim which lacks any evidence whatsoever.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Best proofs of evolution

Postby tomandlu » Fri Apr 05, 2013 7:40 pm UTC

TB I'm calling troll, but I'm willing to play along. I still have no idea whether or not you grasp the basic principles of the theory of evolution. You seem intent on obfuscation at every step. Do you understand the basic theory or not? variation -> selection -> inheritance?
How can I think my way out of the problem when the problem is the way I think?

User avatar
PM 2Ring
Posts: 3707
Joined: Mon Jan 26, 2009 3:19 pm UTC
Location: Sydney, Australia

Re: Best proofs of evolution

Postby PM 2Ring » Sat Apr 06, 2013 7:49 am UTC

I read the first few posts here when the thread was fresh, but I've only just finished reading it.

I get the idea that Ben wants to know what observations allow us to conclude that the theory of evolution via natural selection is a better explanation for the current diversity of species than the traditional religion-based picture of the biosphere simply starting out with a large variety of species, with some of the original species having since become extinct and others having undergone minor changes.

I guess the simple answer to this is that we see the diversity generally increasing over time, which is consistent with evolution, rather than decreasing as we'd expect with special creation.

Of course, comparing these two as if they were equally valid competing theories is misleading at best. The traditional picture doesn't give any mechanism to explain where all those original species came from; OTOH, modern science doesn't (yet) explain abiogenesis.

Science says that the complexity arose through evolution. (Some) religion says that the system was created in a complex state by a complex agent, since religion has difficulty in accepting that a non-directed process can lead to a complex system from simple beginnings.

But science isn't just speculating that complexity can evolve: we have evidence, not only in the form of the fossil record, but through using evolutionary algorithms on computers. So the scientific picture gives a simpler explanation, since it can explain the development of complex systems mechanistically, whereas the traditional picture has to import the complexity from a pre-existing source.

Technical Ben
Posts: 2986
Joined: Tue May 27, 2008 10:42 pm UTC

Re: Best proofs of evolution

Postby Technical Ben » Sat Apr 06, 2013 10:00 am UTC

Sorry, I mean Bioluminescence, not photoluminecence.

Izawwlgood wrote:
Spoiler:
Ben, I think it would be really helpful for your own understanding if you stopped trying to force these poor fitting analogies into your concept of evolution, and instead started listening to the replies explaining your miscommunications.

Technical Ben wrote:So do I assume the ideal mutation rate is met? How do I confirm the lack of extinction of one species is due to adaptation, mutation and evolution, and the extinction of another is due to it's inability to adapt?

You asking this indicates you haven't been listening; adaptation is a process mediated by pressures selecting for traits which are produced by mutations and variation.

Extinction is caused when an organism cannot adapt to the pressures. Selection pressures are such because they change the reproductive potential of an individual; for example, if an organism survives best in 80 degree water, and suddenly finds itself in 60 degree water, what do you think will happen to it, and more importantly, what do you think will happen to subsequent generations of this organism if they remain in 60 degree waters?

In 60 degrees water they reproduce slower. The population in 80 degree water reproduces quicker. This is an observation of population only. Not of mutations. How do I confirm my observation of the population difference, is related to mutations and not just environmental factors? If there are mutations, then how are the two populations observed to be different? Different numbers or speed of reproduction? How do I know this is a "difference" in mutation and not in environment (as applied to historic populations. As said, we can observe the DNA in current ones)? How do I confirm there is any change in their genotype, also that the change in population is correlated (to at least fall close to an observation) to effects in population growth? (I actually have 2 populations sitting beside my desk like this right now. Not quick enough reproduction rate to observe any changes though, other than the one we already agree exists, variation of cats and dogs, fish and birds etc. I can observe variety in these. How do I confirm I can make/select for/indirectly observe changes in mechanical functions and the entire spectrum of life?).

Technical Ben wrote:How do I confirm their parents had 1) a mutation 2) a mutation that was passed on by inheritance? I can do this for current observations and living things. How do we apply it to now extinct animals? Are they not already extinct?

This has already been answered; not all mutations are heritable, so, the way you can confirm if a particular mutation is heritable is if it is found in a single pedigree. I.e., if a mutation is found in a given animal and is a heritable mutation, you will expect to find it in passed on in lineages. If it is a spontaneous mutation, you will find it occurring randomly.

Ok. So to what degree is the statement "A cat produces cats" or "a dog produces dogs" wrong? See, I don't agree with creationists, their comments don't match observation (I observe the earth is not 6000 years old). But does that mean we disagree because I do make observations such as "a cat produces cats"? If I see the current description of evolution acting against such a statement, would I be concerned about how others are applying observations?

PolakoVoador, that requires me to assume similar phenotype is correlated to similar genotype, does it not?

gmalivuk wrote:Yes. Even if we had never observed the effects of mutations in fruit flies, that would be by far the most parsimonious explanation imaginable.

For some I agree. For others not so much. Or did no one consider aether theory the best fit? Or particles to be better than waves? As said, I can observe systems have limit, and some apply to all areas, others do not. Yet more require us to make more observations to get better understanding. I don't so far accept that evolution fits all the observations, though it does fir variation from what I've seen so far. It's more correct in these areas. I'd not make assumptions it fits the others until I've tested (indirectly, I'm not the scientist, I'd accept others tests that fit) out those assumptions. The prevention would be the same that prevents us from dealing 2 decks of cards that are the same. If I can see that the probabilities favor the mutations and the results, then that is fine (I'm rolling 6s with a 6 sided dice and 1000s of tries). If not, I'm stuck here dealing out decks of cards hoping. If the mechanism is complex, then what do we call such a complex system of selection?

Thanks Pm2Ring. At which point, is our conflict in what fits "variety" not similar to what fits "intelligence"? We both see the same thing, but use different words, being a we speak different "languages". Someone refusing to learn a new word, is not the same as someone having difficulty learning the new word. I would agree to through out a creationists theory but I'd not be keen on throwing the observations along with it. Hence any acceptance of a theory would be "this one fits the observation" to me, not "this one is better than the competing", because it's easy to find a worse theory, that does not make mine any better does it? :P

So sorry if it takes me a long time to go over these things. I'll try to concentrate on just one subject and not try to go over all of them, as that's rather too much in one go.
Last edited by Technical Ben on Sat Apr 06, 2013 10:11 am UTC, edited 1 time in total.
It's all physics and stamp collecting.
It's not a particle or a wave. It's just an exchange.

User avatar
yurell
Posts: 2924
Joined: Sat Nov 13, 2010 2:19 am UTC
Location: Australia!

Re: Best proofs of evolution

Postby yurell » Sat Apr 06, 2013 10:07 am UTC

Technical Ben wrote:Ok. So to what degree is the statement "A cat produces cats" or "a dog produces dogs" wrong? See, I don't agree with creationists, their comments don't match observation (I observe the earth is not 6000 years old). But does that mean we disagree because I do make observations such as "a cat produces cats"? If I see the current description of evolution acting against such a statement, would I be concerned about how others are applying observations?


The statement is 0% wrong. A dog produces a dog, and all its descendants will also be dogs. An ape produces apes, and so all its descendants will be apes — that's why we are apes, and why birds are dinosaurs.
I love this little interlude from AronRa:
Foundational Falsehoods of Creationism wrote:For example, “Primates” are collectively defined as any gill-less, organic RNA/DNA protein-based, metabolic, metazoic, nucleic, diploid, bilaterally-symmetrical, endothermic, digestive, tryploblast, opisthokont, deuterostome coelemate with a spinal chord and [twelve] cranial nerves connecting to a limbic system in an enlarged cerebral cortex with a reduced olfactory region inside a jawed-skull with specialized teeth including canines and premolars, forward-oriented fully-enclosed optical orbits, and a single temporal fenestra, -attached to a vertebrate hind-leg dominant tetrapoidal skeleton with a sacral pelvis, clavical, and wrist & ankle bones; and having lungs, tear ducts, body-wide hair follicles, lactal mammaries, opposable thumbs, and keratinized dermis with chitinous nails on all five digits on all four extremities, in addition to an embryonic development in amniotic fluid, leading to a placental birth and highly social lifestyle.

All the children of primates are primates, and so are we.
cemper93 wrote:Dude, I just presented an elaborate multiple fraction in Comic Sans. Who are you to question me?


Pronouns: Feminine pronouns please!

Technical Ben
Posts: 2986
Joined: Tue May 27, 2008 10:42 pm UTC

Re: Best proofs of evolution

Postby Technical Ben » Sat Apr 06, 2013 10:13 am UTC

Thanks. If it is a wrong statement, then is it a creationist who is wrong, or their source material that says "a bird produces birds"?
By all means show the wrong theories to be wrong. But don't throw out the observations.
It's all physics and stamp collecting.
It's not a particle or a wave. It's just an exchange.

User avatar
yurell
Posts: 2924
Joined: Sat Nov 13, 2010 2:19 am UTC
Location: Australia!

Re: Best proofs of evolution

Postby yurell » Sat Apr 06, 2013 10:39 am UTC

A bird produces birds is a true statement — the descendent of a bird will always be a bird. We may not end up recognising it as a bird (after all, many people don't immediately recognise a bird as a dinosaur or a human as an ape), but it's still a bird.

Edit: Ah, when I said '0% wrong', I meant '100% right'; that is, the statement is true.
cemper93 wrote:Dude, I just presented an elaborate multiple fraction in Comic Sans. Who are you to question me?


Pronouns: Feminine pronouns please!

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Best proofs of evolution

Postby Izawwlgood » Sat Apr 06, 2013 1:22 pm UTC

Technical Ben wrote:In 60 degrees water they reproduce slower.

No, they reproduce less successfully (which I acknowledged may be a product of 'reproduce slower', but the point is the change in fecundity, a word, by the way, you should know). Meaning, instead of having a fitness of 100% (that is, 'maximally able to reproduce')), they have a fitness of <100% (meaning 'less than maximally able to reproduce'). What will happen in this case is those individuals in the population that are best able to reproduce in 80 degrees reproduce less successfully (say, 50%), while those individuals in the population that are best able to reproduce in, say, 70 degrees will reproduce more successfully (say, 80%). The selection pressure of the cold, acting on the reproductive success of each generation, will produce a population that prefers the cold.

Organisms in equilibrium with their environment with produce exactly one offspring to replace them. Doesn't matter if they're salmon spawning thousands of fry, or elephants having one calf every 2 years that they have to care for until it's at least 5 years old; in a state of population equilibrium, each individual manages to successfully reproduce to replace itself.

I asked you this question because you were asking about 'mutation rates not being met'. So, tell me, what do you think will happen if a species finds itself in colder water, and is unable to adapt to it? Do you understand how if it fails to produce subsequent generations of adapted individuals, and can only produce offspring that have a fitness of 'not able to replace myself in the subsequent generation', that the species will die out in that environment? If that mutation rate does not produce sufficient variation in the population to get it to the point where it's fitness is 100%, it will decline and become extinct.

Technical Ben wrote:How do I know this is a "difference" in mutation and not in environment

You mean, like how do you know that the average height in humans is based on genetics not on 'sufficient caloric intake during puberty', if you were only looking at a fossil record of humans? My supposition is that with enough specimens you can get an average that eliminates samples that include those who endured starvation events, or more to the point, there are other markers that will indicate starvation events like bone ossification anomalies, etc.

Technical Ben wrote:How do I confirm there is any change in their genotype

Assuming you're talking about fossil records; if a change to genotype does not produce a change to phenotype, and don't have multiple generations to study, you cannot confirm any change occurred. Silent mutations are silent.

Technical Ben wrote:But does that mean we disagree because I do make observations such as "a cat produces cats"? If I see the current description of evolution acting against such a statement, would I be concerned about how others are applying observations?

I think your mistake here is not understanding that 'cats produce cats' means there could next be evolutionary pressures that could cause a proto-feline's lineage to 'become' the lynx and the lion. We're not talking about 'proto-cat doing it's thing, doing it's thing, has some kittens, BAM, mutations!, one of those kittens is a fucking puma! and one of those kittens a fucking house cat! and one of those kittens is a fucking tiger!'
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Best proofs of evolution

Postby tomandlu » Sat Apr 06, 2013 3:35 pm UTC

Technical Ben wrote:Thanks. If it is a wrong statement, then is it a creationist who is wrong, or their source material that says "a bird produces birds"?
By all means show the wrong theories to be wrong. But don't throw out the observations.


Note that something cannot really stop being what its ancestors were, but it can start being something they weren't. Birds are dinosaurs, but dinosaurs are not birds. Nor should you get hung up on looking for a boundary - there won't be one. This isn't a 'fault' of evolution or of our understanding:

Though no man can draw a stroke between the confines of day and night, yet light and darkness are upon the whole tolerably distinguishable.


Also, don't get to caught up on mutation - it's important, but morphological changes are driven more by the interaction between variation and selection (for the simple reason that such changes generally require a coordinated change in two or more features). Mutations can open up new territory, but they cannot easily explore it, so to speak. Are you expecting offspring to be wildly different from their parents? It can happen, but the chance of such offspring surviving is very remote.

I'm still genuinely struggling to work out what's causing you a problem - perhaps my sig. might help?
How can I think my way out of the problem when the problem is the way I think?

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26738
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Best proofs of evolution

Postby gmalivuk » Sat Apr 06, 2013 4:05 pm UTC

Technical Ben wrote:I observe the earth is not 6000 years old.
No, you don't.

You don't observe that the Earth is really old. You only observe that it exists now with a bunch of characteristics most easily explained by great age.
You don't observe that there's fusion going on in the Sun. You only observe that it's big and really hot and has a particular spectrum most easily explained by fusion at its core.
You don't observe that the planets orbit the way they do because gravity. You only observe that they move around in paths most easily explained by the theory of gravity.

The rest are all things you can deduce from the things you observe, much like the historical changes in biological life due to evolution by natural selection.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

Technical Ben
Posts: 2986
Joined: Tue May 27, 2008 10:42 pm UTC

Re: Best proofs of evolution

Postby Technical Ben » Sat Apr 06, 2013 5:24 pm UTC

lzawwlgood does "successful" suggest a goal? Life has no goal to reproduce under a scientific eye, does it? The speed of reproduction may cause variation in the population size (and thus size of a particular of genotype/phenotype in that population), but is that a more or less "success"?

I get a greater population of creatures that can reproduce in the cold. Ok. That follows. Population equilibriums are observed also. How do I add to this the variation? Or the addition of variation? I can see the reduction of variation. I can see the change in distribution or numbers of each variation. How do I observer or correlate it to new variations?

Define "unable to adapt". Is that unable to reproduce at all, or able to reproduce slower? Are we talking about animals able to respond to their environment (single generation, thus response is per animal)? Or are we only talking about adaptation over subsequent generations (which I can assume for mutation for the point of the discussion)? If the cold kills it, it dies. If it does not, it can either carry on until the cold is gone (change in the environment), or adapt to it as you say. How do I confirm what type of adaptation is applied to the creature? (I think we talked about e-coli adapting at one point?) If the fitness rate is not 100% and the environment does not change. Or are we assuming the 100% applies to a moving target of the environment (so we take a new 100% marker each measure of the environment?) If we assume the environment does not change, then we cannot apply evolution, because there is no change in selective pressure, there is no variance. Is that correct?

You mean, like how do you know that the average height in humans is based on genetics not on 'sufficient caloric intake during puberty'...
Yes. I would need to go over such things more so. As I'd have to confirm that, and that these are "new" specimens that were not there in the past. If there was a variation in the past I could consider both populations exist throughout. To add to that, I would also have to confirm that a "change in height" is not something available within the genome without mutation (chromosome inheritance? Or any mechanism that can be inherited for, but does not require mutations).

If silent mutations cannot be observed, to confirm a theory fits the observed fossil record, can I do so with other mutations or by other means?

Izawwlgood, I know that more than one generation is required. And that evolution considers gradual steps. We can confirm with good confidence if there is fusion in Jupiter or not. By looking at the figures, the mass, the composition, etc. I'd like to be able to do the same here. If I cannot, I cannot say with confidence if evolution fits the observation in all areas. So, the degree and speed of things such as mutations is important. If I can observe 1 or 2 mutations having a result, to be able to confirm the figures (population size, number of generations) matches the predictions and observations, then I can have confidence in it.

So I've seen life gets enough cards dealt to gain a hand (generation) that matches another hand (environment). Show that it gets enough hands to progress from there.

Gmalivuk. Then can we agree to both use the term that way? We do not "observe evolution" we "deduce evolution". I can accept that standpoint, but I may be free to wait until I can deduce the same. Is that fair? Can I for example observe fossils? What allows me to deduce their hereditary line?
It's all physics and stamp collecting.
It's not a particle or a wave. It's just an exchange.

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Best proofs of evolution

Postby Izawwlgood » Sat Apr 06, 2013 6:02 pm UTC

Technical Ben wrote:The speed of reproduction may cause variation in the population size (and thus size of a particular of genotype/phenotype in that population), but is that a more or less "success"?

Again, you shouldn't think of 'reduced reproductive success' to mean 'reproduces more slowly'. This is part of the issue with this conversation with you; we keep giving you answers, and you keep deliberately misunderstanding what we are saying.

The 'speed of reproduction' may be reduced in the cold water example, but whether reproduction is faster, slower, results in more/less, bigger/smaller, taller/shorter offspring isn't the point. The point is that in this example, reproduction is less successful, that the fecundity of individuals in their new environment is reduced. Again, I want you to look up that word.

Technical Ben wrote:I get a greater population of creatures that can reproduce in the cold. ... How do I observer or correlate it to new variations?

I don't understand what you are stating and then asking here. The bolded doesn't make sense to me. The italicized doesn't either. The bolded sounds like you're saying 'subsequent generations in this environment will produce a population that prefers reproducing in the cold'? Is that correct?
I provided this analogy to demonstrate what happens when 'mutation rates are insufficient to allow a species to adapt'. The analogy underlines that reducing the fecundity of maladapted individuals selects against them, and that unless fecundity is high enough to bring the population to a population equilibrium state, the species will die off. If reproductive success is less than 'able to replace self in subsequent populations', the population equilibrium will trend towards extinction.
To the italicized, it sounds like you're asking how you observe new variation? You examine a population and take data on it.

Technical Ben wrote:Define "unable to adapt". Is that unable to reproduce at all, or able to reproduce slower?

Again, not necessarily 'slower', but 'less successfully'. Successful here means 'being able to replace yourself in the next generation'. If a population has a lower fecundity in a given environment, the population will trend to extinction. If the population has a higher fecundity in a given environment, the population will increase. By 'unable to adapt', I mean, 'remain in a state of reduced fecundity'. Remember, we aren't talking about individuals here, but populations over generations.

Technical Ben wrote:If we assume the environment does not change, then we cannot apply evolution, because there is no change in selective pressure, there is no variance. Is that correct?

This is incorrect, and I truthfully have no idea how you came this any of the statements or conclusions in this statement.
For one, remember that populations of organisms are not static; I'm am quite sure you are familiar with the word 'migration'? Secondly, selective pressure does not cause variation. Thirdly, your use of the phrase 'apply evolution' seems very odd to me. Fourthly, 'change in selective pressure' is not a requirement for a pressure to be selective (although I suppose 'selection pressure' can be particularly in reference to something that is changing about an environment...)

Technical Ben wrote:If there was a variation in the past I could consider both populations exist throughout.

This is another example of why your lack of knowledge in the topic is preventing meaningful or informative dialog; you need to look up the term 'speciation' now.

Technical Ben wrote:Show that it gets enough hands to progress from there.

Sorry? You're asking me to prove that life as it exists in all it's diversity... exists in all it's diversity?
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

niky
Posts: 92
Joined: Fri Jul 09, 2010 6:34 am UTC

Re: Best proofs of evolution

Postby niky » Sat Apr 06, 2013 6:16 pm UTC

Technical Ben wrote:I'd like to be able to do the same here. If I cannot, I cannot say with confidence if evolution fits the observation in all areas.


This is the problem. You happily deduce that fusion is not happening in Jupiter because you have data on what signs to look for in fusion.

Yet, you cannot accept that evolution and speciation occurs in instances where you cannot directly observe because... why?

That's like asking whether the rest of the stars in the sky are lit by fusion and not some heretofore unknown effect.

The outward signs are already there, and have been pointed out. What you're asking for, instead, is direct observation of fusion happening firsthand (or something of the sort, your questions are very confusing because of the way you mangle the terminology) at a distant star... which is not going to happen.

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Best proofs of evolution

Postby Izawwlgood » Sat Apr 06, 2013 6:30 pm UTC

Yeah, to repeat what's been said a few times, Ben, you're inability to understand a theory that you have very little foundational comprehension of does not mean the theory is invalid. Nor do the gaps in your comprehension indicate gaps in the theory.
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

User avatar
jules.LT
Posts: 1539
Joined: Sun Jul 19, 2009 8:20 pm UTC
Location: Paris, France, Europe

Re: Best proofs of evolution

Postby jules.LT » Sat Apr 06, 2013 10:22 pm UTC

tomandlu wrote:TB I'm calling troll

Image
(Sorry, couldn't resist)
Bertrand Russell wrote:Not to be absolutely certain is, I think, one of the essential things in rationality.
Richard Feynman & many others wrote:Keep an open mind – but not so open that your brain falls out

User avatar
PolakoVoador
Posts: 1028
Joined: Fri Jun 10, 2011 11:11 pm UTC
Location: Brazil

Re: Best proofs of evolution

Postby PolakoVoador » Sat Apr 06, 2013 11:06 pm UTC

This is Steve Waterman all over again

User avatar
yurell
Posts: 2924
Joined: Sat Nov 13, 2010 2:19 am UTC
Location: Australia!

Re: Best proofs of evolution

Postby yurell » Sat Apr 06, 2013 11:37 pm UTC

Technical Ben wrote:lzawwlgood does "successful" suggest a goal? Life has no goal to reproduce under a scientific eye, does it?


TB, the organism doesn't define 'success', we do, and in the manner that Izawwlgood keeps explaining to you. We don't care if a species thinks dying out is the greatest thing ever, it's not how we define reproductive success. For example, I don't need to have a goal to be a successful dog owner, as defined by some other individual — I either will be or won't be based on what the result of my actions are, not my intent behind it. You can call me reproductively unsuccessful because I will never be able to have children, and it's true regardless of whether I ever intended to or not.
cemper93 wrote:Dude, I just presented an elaborate multiple fraction in Comic Sans. Who are you to question me?


Pronouns: Feminine pronouns please!

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Best proofs of evolution

Postby tomandlu » Sun Apr 07, 2013 7:54 am UTC

jules.LT wrote:
tomandlu wrote:TB I'm calling troll

Image
(Sorry, couldn't resist)


The bit I'm puzzling out is whether he's a conscious or unconscious troll.
How can I think my way out of the problem when the problem is the way I think?

Technical Ben
Posts: 2986
Joined: Tue May 27, 2008 10:42 pm UTC

Re: Best proofs of evolution

Postby Technical Ben » Thu Apr 11, 2013 11:44 am UTC

Izawwlgood. I'm happy to accept the two are different. But I need assistance in seeing how they are. So the speed of reproduction is different to the reproductive success. Sorry if I'm having difficulty grasping what the difference is.

The analogy underlines that reducing the fecundity of maladapted individuals selects against them.

How do I observe that these selections apply to the extent to either 1) remove all of the specific genotype from existence in all populations (thus I can confirm evolution is correct in describing how species disappear) and 2) add new genotypes that did not exist in the population already (so I can confirm evolution is correct in describing how new species appear)?

I can have a population with a variation. I give it a genotype which I represent with a number. We give it a value of 1 to 5. The variation can be added to or subtracted from as a mutation. I can add up to 5, or reduce to 1. I can have a population consisting only of genotype 1, or a population including all types (1 to 5). Now, I can let reproduction change the size of the populations, they can also inherit mutations etc. I can let the environment select from this population, with a requirement for a certain value or range of values. I get a selection against fitness here? I can visualize how the numbers, variations, populations, inheritance would progress here.

Is that a correct example? If I then consider each genotype above to be unable to interbreed, I end up with separate species. I end up with extinction if the genotype does not match the environment. However, what if I set up two experiments of the above, one with a starting point of one species only given the value 1, and the other where I start with 5 species (1 to 5)? How do I look back over the set of species, to tell which experiment started with the variation at the begging (then continued to meet the environment and selective pressure) and which started with no variation (then met the environment and selective pressure)?

That's not trolling. It's asking how I can measure the difference in a system that starts with variety and continues, and one that starts with none and increases it.

Again, not necessarily 'slower', but 'less successfully'.

Ok, this is where I'm not understanding. A value of the number of successful reproductions can also be taken as a total of the number of successful reproductions of the species over time, can it not? "Number of successful reproductions + time between reproduction = total success"? Or is it that a slower reproduction rate can be selected for, because some environments favor slower reproduction (cold or seasonal areas. an example being a 7 year arctic moth http://en.wikipedia.org/wiki/Gynaephora_groenlandica)? If that is where I've gone wrong, I'll be happy to change from "reproduction speed == reproduction success" to "any factor effecting reproduction success == reproduction success".

For one, remember that populations of organisms are not static; I'm am quite sure you are familiar with the word 'migration'? Secondly, selective pressure does not cause variation.

If I have a population with mutation only, and allow it to grow unrestricted (no selective pressure), then I get a larger population of types that reproduce the quickest? Would that be correct. Without selective pressure or environmental factors, the only thing to change the number of specimens in a population, is the speed they reproduce? If my environment is static, I only get 1 type of species that is "fittest", is that correct? As they reach the most efficient fitness, and then have nothing else to be selected for?

I know some of the definitions of speciation. But if speciation refers to evolution, does it help me know what evolution is? I'd have to ask what both are, as one requires the other in it's explination. How do I understand one or the other from a starting point? I can consider speciation, but under what observations? If speciation is not variation (I agree it's not), how do I confirm the observance of it in a population is new? How do I confirm that I have an origional population progressing to a new speciation, and not a mixed population of 2 species progressing to one species? As said, not to be argumentative, but to look at how to demonstrate, derive or observe the fact. Just as it's easy to state something is true, but to provide a proof requires more questions and more work.

Sorry? You're asking me to prove that life as it exists in all it's diversity... exists in all it's diversity?

No, how do I confirm how it got it's diversity. I observe it has diversity. I observe it has some "hands" in a card game. How do I know how many hands in the game it had previously? How do I know what rules it got them by? I can observe the current game (current diversity). I'm asking how we go about observing the past hands so as to say "we know the rules that the game is played by". I can conceive any number of theoretical ways to get to this hand (or deck). I consider evolution a possible way. How do I go about confirming this is the most fitting? Would I not check we had enough hands dealt, enough selections, enough cards etc? The numbers are very important, as some are too low a probability to consider possible, some are so high it's foolish to not consider them factual.
It's all physics and stamp collecting.
It's not a particle or a wave. It's just an exchange.

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Best proofs of evolution

Postby Izawwlgood » Thu Apr 11, 2013 12:50 pm UTC

Technical Ben wrote:Izawwlgood. I'm happy to accept the two are different. But I need assistance in seeing how they are. So the speed of reproduction is different to the reproductive success. Sorry if I'm having difficulty grasping what the difference is.

You need to look up the word 'fecundity'. I'm serious; this conversation cannot continue until you do so.
Technical Ben wrote:How do I observe that these selections apply to the extent to either 1) remove all of the specific genotype from existence in all populations (thus I can confirm evolution is correct in describing how species disappear) and 2) add new genotypes that did not exist in the population already (so I can confirm evolution is correct in describing how new species appear)?

By understanding the basics of Evolutionary Biology, and reading about all the examples of observation of evolution.
Again! You're mistaking 'selection' for 'mutation'. Selection does not make new genotypes, mutation makes new genotypes. Selection SELECTS for which genotypes are passed on.
Technical Ben wrote:I can have a population with a variation. I give it a genotype which I represent with a number. We give it a value of 1 to 5. The variation can be added to or subtracted from as a mutation. I can add up to 5, or reduce to 1. I can have a population consisting only of genotype 1, or a population including all types (1 to 5). Now, I can let reproduction change the size of the populations, they can also inherit mutations etc. I can let the environment select from this population, with a requirement for a certain value or range of values. I get a selection against fitness here? I can visualize how the numbers, variations, populations, inheritance would progress here.

Is that a correct example? If I then consider each genotype above to be unable to interbreed, I end up with separate species. I end up with extinction if the genotype does not match the environment. However, what if I set up two experiments of the above, one with a starting point of one species only given the value 1, and the other where I start with 5 species (1 to 5)? How do I look back over the set of species, to tell which experiment started with the variation at the begging (then continued to meet the environment and selective pressure) and which started with no variation (then met the environment and selective pressure)?

This analogy is weirdly wrong in a way I'm having trouble looking at. Please look up 'Punnett Square' to get on board with how we talk about genotypic variation and inheritance, maybe? I'm not really sure what your mutations are doing, other than turning genotypes into other genotypes, which they don't really do, as you have it. But yes, assuming genotype 1, 2, 3, 4, and 5 have known fitness functions, you can indeed model them.
The problem with this analogy is the way you think mutation works, but yes, you could track the population over time then.

Technical Ben wrote:It's asking how I can measure the difference in a system that starts with variety and continues, and one that starts with none and increases it.

By looking at the fossil record. We've said this to you numerous times. Or by looking at how prevalent a given gene sequence is in a given population; if it's in everyone, it's probably older! If it's only a few people, it's probably younger, or spontaneous!

Technical Ben wrote:Ok, this is where I'm not understanding. A value of the number of successful reproductions can also be taken as a total of the number of successful reproductions of the species over time, can it not? "Number of successful reproductions + time between reproduction = total success"? Or is it that a slower reproduction rate can be selected for, because some environments favor slower reproduction (cold or seasonal areas. an example being a 7 year arctic moth http://en.wikipedia.org/wiki/Gynaephora_groenlandica)? If that is where I've gone wrong, I'll be happy to change from "reproduction speed == reproduction success" to "any factor effecting reproduction success == reproduction success".

Fecundity. Look it up, and reread my previous posts response to your confusion. Reproduction success is the definition you want (as this is basically the definition of fecundity)
Technical Ben wrote:I know some of the definitions of speciation. But if speciation refers to evolution, does it help me know what evolution is? I'd have to ask what both are, as one requires the other in it's explination. How do I understand one or the other from a starting point? I can consider speciation, but under what observations? If speciation is not variation (I agree it's not), how do I confirm the observance of it in a population is new? How do I confirm that I have an origional population progressing to a new speciation, and not a mixed population of 2 species progressing to one species? As said, not to be argumentative, but to look at how to demonstrate, derive or observe the fact. Just as it's easy to state something is true, but to provide a proof requires more questions and more work.

Respectfully, you do not seem to understand the definitions. And your lack of understanding does not indicate that the problem is a lack of proof.
You seem to be very caught up in how YOU can observe something. Lets get something straight; it doesn't matter if you go into the field and start looking for these things, because you don't know what you're looking for. You can't come into a lab, be shown some sequencing data, and expect to understand how selection pressure on mutations in a given environment give rise to citrate consumption. You are a layman, and until you understand the field, you WILL have to accept some of these statement sans nuanced data backing them up. Because this whole discussion, we've been explaining things to you, and our explanations are based on conclusions that have been reached from observation.
But sure; you can observe speciation by either observing that two populations no longer breed, or by finding mutations in one population that are not found in another. For example, Alu transposon insertion at locus ### (I can't remember what locus it is) has been used to track human populations, because it is a fairly recent insertion.
Technical Ben wrote:No, how do I confirm how it got it's diversity. I observe it has diversity. I observe it has some "hands" in a card game. How do I know how many hands in the game it had previously? How do I know what rules it got them by? I can observe the current game (current diversity). I'm asking how we go about observing the past hands so as to say "we know the rules that the game is played by". I can conceive any number of theoretical ways to get to this hand (or deck). I consider evolution a possible way. How do I go about confirming this is the most fitting? Would I not check we had enough hands dealt, enough selections, enough cards etc? The numbers are very important, as some are too low a probability to consider possible, some are so high it's foolish to not consider them factual.

You should really ditch this analogy.
So, you've been made aware of a theory that explains how the hand size can become diverse, and you are aware of methods for that diversity to occur. Show me where the numbers are 'too low a probability to consider possible'.
Basically, you've set up a poor analogy, that you've been told isn't terribly representative, and you posit that in your analogy some things don't fit, and now you think it's the theories job to explain away the inconsistencies in your analogy?
Last edited by Izawwlgood on Thu Apr 11, 2013 2:19 pm UTC, edited 1 time in total.
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26738
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Best proofs of evolution

Postby gmalivuk » Thu Apr 11, 2013 1:36 pm UTC

Ben, how about you just stop talking about cards and hands entirely. Everyone is trying to help you understand by talking about actual biological things, and the least you could do is start talking about actual biological things along with them. Which of course also requires you to actually make an effort to understand the terminology involved.

If you are unwilling or unable to do that, then you should stop posting in this thread.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)


Return to “Science”

Who is online

Users browsing this forum: No registered users and 20 guests