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Discussion of everything related to the Theory of Evolution.
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by gamila » Thu Aug 27, 2009 5:01 am
Do you have a better definition? If no, then please tell me you do not have one.
i dont have one You can quote mine all you like, it doesn't change that fact.
fact is as this site notes note it says heritable traits It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism.
Can parents that exhibit the traits of blood type A and blood type B produce offspring that have the trait of blood type o? If so, then you are wrong about the inheritance of traits. ns is about traits already being present being passed on as the quote above shows if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism.
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by GaryGaulin » Thu Aug 27, 2009 9:13 am
gamila wrote: Do you have a better definition? If no, then please tell me you do not have one.
i dont have one
Thanks Gamila for being so honest! I'm now wondering what you think of this explanation. With any definition being difficult to word I expect you might find something wrong with it too but your honest opinion of it would be helpful. SpeciationSpeciation is a process where a population so much changes from the population they once were that they have gone their separate ways. Where still able to have offspring the entire population no longer chooses to pair-up together. Or a population that became isolated from another can experience genetic drift that forces them forever apart. In some cases speciation happens very slowly by taking small learning steps, one gene or epigentic switching change at a time. In other cases it is immediate, with no transitional fossils possible. How long it would take an isolated genome to slowly speciate depends on its learning rate (how fast it gains or changes new information/genes). Sexual reproduction has a good amount of crossover exchange which greatly accelerates the ability to adapt and change. Asexual reproducers such as E. coli produce clones of itself which are identical to the parent. Fast responses to environment is then from exchanging plasmids but these are separate transient genomes, not the primary genome that accomplishes cell growth and reproduction. There are "living fossils" that have changed so little it seems to us that they should have become a new species by now or at least new morphology. But this change is relative to how fast our genome changes in comparison to theirs. So it is not time alone that matters, we must also consider the genome learning rate in our consideration of how long it takes for a given genome to speciate.
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by gamila » Thu Aug 27, 2009 11:10 am
Speciation is a process where a population so much changes from the population they once were that they have gone their separate ways. Where still able to have offspring the entire population no longer chooses to pair-up together. Or a population that became isolated from another can experience genetic drift that forces them forever apart.
Speciation is a process where a population so much changes from the population they once were that they have gone their separate ways. Where still able to have offspring the entire population no longer chooses to pair-up together.
1) so is the new population the same as or different to the antecendant population 2} if the populations can still breed fertile offspring what makes them different species Or a population that became isolated from another can experience genetic drift that forces them forever apart..
can the different populations have fertile offspring if yes then what makes them different species or if they cant what makes your definition different from those who say different species cant breed fertile of spring from the look of your definition you are saying two things 1_ different species can breed 2 the same species can breed we are left wondering just what a species is
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by robsabba » Thu Aug 27, 2009 2:48 pm
gamila wrote: You can quote mine all you like, it doesn't change that fact.
fact is as this site notes note it says heritable traits It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism.
Can parents that exhibit the traits of blood type A and blood type B produce offspring that have the trait of blood type o? If so, then you are wrong about the inheritance of traits. ns is about traits already being present being passed on as the quote above shows if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism.
OK, now I think I understand your problem with NS. First off, natural slection does not require all traits, or even all traits under selective pressure, to be one inheritable as a discret unit. Quantitative traits, (under multiple gene control, like height in humans) can be put under selective pressure, just as qualitative traits that are under the control of a single gene. Let's look at an example of how this works. I told you already about the fruit fly experiment, where after a number of generations, two populations were selected for that fell outside the original population's range for bristle hair number. This is a quanitative trait, determined by multiple genes. Another example which is from a natural situation is beak size in birds. In particular, Darwin's finches in the Galapagos islands. During a period of drought, small-seed plants began to dominate the flora and there was selective pressure for reduced beak size in the finches living there who depended on those seeds. As a result, the finches evolved to have smaller beaks. Keep in mind, that beak size is represented by a range of sizes. The result of evolution was that that range was shifted to the smaller end. Another example would be the peppered moths famous in England. Most were white because they could blend in with the lichens growing on the trees which camoflauged them from hunting birds. However, there were always a small number of dark colored moths. These moths were kept down in number due to the fact they were easier to hunt. With industrialization, the lichens died on the trees and smut covered the trees making them dark. Now, the dark colored moths had the advantage over the white ones, and the populations evolved to be mostly black. This inheritance is more stright foward, under the control of one or two genes. Thus, you are either white or black, but not inbetween (unlike beak size). Neither of these examples resulted in speciation. It normally takes multiple such events to make a population different enough from the mother population to stop mating with that mother population. The creation of a population that either cannot or will not bred with the original is the definition of speciation in species that unergo sexual reproduction. How can such changes result in reproductive isolation as I just defined it? One interesting example is changes in bird beak size brought on by changes in diet. In songbirds, the size of the beak affects the song that the birds sing. It has been documented that changes in beak size brought on by changes in diet can alter the song that birds sing to find mates. This can then result in the reproductive isolation of a population from its original population. Keep in mind this type of change is gradual, and that populations evolve, not indiviuals. That is just one example.
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by robsabba » Thu Aug 27, 2009 3:01 pm
gamila wrote: can the different populations have fertile offspring if yes then what makes them different species or if they cant what makes your definition different from those who say different species cant breed fertile of spring
from the look of your definition you are saying two things 1_ different species can breed 2 the same species can breed
we are left wondering just what a species is
Let's look at lions and tigers. Lions and tigers do not interbred in nature, yet can be made to under artificial (human controlled) conditions. Because they do not interbred under natural conditions, they are considered separate species. This does leave us with a question, however. If they do not have a common ancestor, why are they able to interbred under artificial situations?
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by gamila » Thu Aug 27, 2009 3:39 pm
OK, now I think I understand your problem with NS. First off, natural slection does not require all traits, or even all traits under selective pressure, to be one inheritable as a discret unit
as i said ns is about traits already being present being passed on as the quote above shows if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on
Because they do not interbred under natural conditions, they are considered separate species.
self contradiction you say they are different species but they can breed which means they are the same species just look at deans example of the bactrian and dromardy camels your qualification of artifical is just sophism fact is speciation shows ns is wrong to quote NS is all about the transmission of already acquired traits if evolution can take place by speciation i.e. a new species has new traits that are not present in the antecedent species thus NS is invalid as it cannot account for speciation
But invertebrate by definition means “not a vertebrate.” Evolve means to change, and a changed thing is not what it once was, by definition. Thus the example can be reduced to absurd and useless repetition: something evolved from what it was not. The end result of the phrase is merely an assumption, not a demonstration. Evolution in this way assumes itself, cloaked in logical fallacy.”
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by robsabba » Thu Aug 27, 2009 4:37 pm
gamila wrote: OK, now I think I understand your problem with NS. First off, natural slection does not require all traits, or even all traits under selective pressure, to be one inheritable as a discret unit
as i said ns is about traits already being present being passed on as the quote above shows if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on
Look. I put some effort into trying to explain how NS actually works, rather than your stawman version. You are just ignoring my previous post and repeating yourself. gamila wrote: Because they do not interbred under natural conditions, they are considered separate species.
self contradiction you say they are different species but they can breed which means they are the same species just look at deans example of the bactrian and dromardy camels your qualification of artifical is just sophism fact is speciation shows ns is wrong
There is no contradiction. I gave you the definition as it is actually used in the real world. You did not answer my question, which is why these different animals are able to interbred if they do not have a common ancestor. How about answering my question now? gamila wrote: to quote NS is all about the transmission of already acquired traits if evolution can take place by speciation i.e. a new species has new traits that are not present in the antecedent species thus NS is invalid as it cannot account for speciation
But invertebrate by definition means “not a vertebrate.” Evolve means to change, and a changed thing is not what it once was, by definition. Thus the example can be reduced to absurd and useless repetition: something evolved from what it was not. The end result of the phrase is merely an assumption, not a demonstration. Evolution in this way assumes itself, cloaked in logical fallacy.”
Now you are just repeating yourself and ignoring my responses. I think you are just wasting my time. Hopefully a few lurkers got something out of this, at least.. One last time: Populations Evolve Not Individuals!
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by gamila » Fri Aug 28, 2009 5:37 am
Look. I put some effort into trying to explain how NS actually works, rather than your stawman version. You are just ignoring my previous post and repeating yourself.
ignoring nothing your talk of moths and your blood example as has been pointed out shows ns is wrong if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on
you said Neither of these examples resulted in speciation.
but we are talking about speciation and as such speciation shows ns is wrong you have even said Yes, "something evolved from what it was not,
thus . Thus the example can be reduced to absurd and useless repetition: something evolved from what it was not. The end result of the phrase is merely an assumption, not a demonstration. Evolution in this way assumes itself, cloaked in logical fallacy.”
fact is ns is about the passing on of already present traits speciation show ns is wrong ns is It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism
as i have already said ns is about traits already being present being passed on as the quote above shows if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on
NS is all about the transmission of already acquired traits if evolution can take place by speciation i.e. a new species has new traits that are not present in the antecedent species thus NS is invalid as it cannot account for speciation
you say There is no contradiction.
i gave you the bactrian and dromadry camel example the bactrian and dromardry camels can breed which means they are the same species but they are different species thus a contradiction your qualification of artifical is just sophism . One last time: Populations Evolve Not Individuals!
perhaps you might like to reply to this thread the colin leslie dean species paradox about15986.html
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by robsabba » Fri Aug 28, 2009 2:22 pm
gamila wrote: Look. I put some effort into trying to explain how NS actually works, rather than your stawman version. You are just ignoring my previous post and repeating yourself.
ignoring nothing
I wrote three paragraphs, and you just repeated your previous posts. gamila wrote:your talk of moths and your blood example as has been pointed out shows ns is wrong if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on
Please listen. One more time. Populations Evolve Not Individuals. Evolution is a Change in Gene Frequency In A Population, not an individual and its offspring alone. gamila wrote:you said Neither of these examples resulted in speciation.
but we are talking about speciation and as such speciation shows ns is wrong you have even said
gamila wrote: Yes, "something evolved from what it was not,
thus . Thus the example can be reduced to absurd and useless repetition: something evolved from what it was not. The end result of the phrase is merely an assumption, not a demonstration. Evolution in this way assumes itself, cloaked in logical fallacy.”
I gave you an example of a reproductive isolation mechanism from the real world-- songbirds-- and you ignored it. gamila wrote:fact is ns is about the passing on of already present traits speciation show ns is wrong ns is It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism
Populations Evolve Not Individuals gamila wrote:as i have already said ns is about traits already being present being passed on as the quote above shows if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on
NS is all about the transmission of already acquired traits if evolution can take place by speciation i.e. a new species has new traits that are not present in the antecedent species thus NS is invalid as it cannot account for speciation
See above gamila wrote:you say There is no contradiction.
i gave you the bactrian and dromadry camel example the bactrian and dromardry camels can breed which means they are the same species but they are different species thus a contradiction
I asked you to explain why animals that are different can interbred. Can you answer my question now? gamila wrote:your qualification of artifical is just sophism .
No. The difference betweeen Artifical and Natural is real. Look them up in a dictionary. gamila wrote:One last time: Populations Evolve Not Individuals!
perhaps you might like to reply to this thread the colin leslie dean species paradox about15986.htm
Why would I reply to another thread where you are repeating yourself over and over and not paying attention to anyone's responses?
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by gamila » Fri Aug 28, 2009 2:37 pm
No. The difference betweeen Artifical and Natural is real. Look them up in a dictionary.
the fact is that the off spring from the bactrian and dromardy camels is real -they did mate in a natural setting the bactrian and dromardry camels can breed which means they are the same species but they are different species thus a contradiction
Populations Evolve Not Individuals
fact is populations are made up of individuals and if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on because ns is It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism
you say Populations Evolve Not Individuals
so lets try this tack- i am not happy with it if the new species population has traits that are not present in its parent population then this shows ns is wrong as ns is about the transmission of already present triats In other words the new species population has new triats not seen before so where did they come from, they could not have come from the parent population as they are new triats and thus not present in the parent population now if they did not come from the parent population they could not have happened due to natural selection as ns is about the parent population passing on already present ie not new triats I asked you to explain why animals that are different can interbred. Can you answer my question now?
no idea but the problem may not be with the animals but be with the classificatory system used which is based on an essentialism
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by robsabba » Fri Aug 28, 2009 5:29 pm
gamila wrote: [you say Populations Evolve Not Individuals
so lets try this tack- i am not happy with it if the new species population has traits that are not present in its parent population then this shows ns is wrong as ns is about the transmission of already present triats In other words the new species population has new triats not seen before so where did they come from, they could not have come from the parent population as they are new triats and thus not present in the parent population now if they did not come from the parent population they could not have happened due to natural selection as ns is about the parent population passing on already present ie not new triats
Let's look at how Darwin defined Natural Selection (paraphrasing) 1. There is variation among indiviuals in a popualtion. 2. That variation is inheritable3. More offspring are produced than can survive long enough to reproduce. 4. Those indivduals that are better adapted to their environment with preferentially survive to reproduce and pass their traits on. Notice anything? The explanation for (1) variation, is not mentioned. This is because Natural Selection does not explain where the variation it acts on comes from. This is where genetics comes in. One source is assortive mating, and another is mutation. Now, what happens during evolution, is there is a shift in the frequency of genes in a population (not individuals!). Individuals which survive to reproduce will pass on their genetic material to offspring, but the genetics of the population is what changes. In the peppered moth example, black moths survived to reproduce which in turn shifted the population from mostly white to mostly black. With the finch example, those birds with smaller beaks survived to reproduce which in turn shifted the population to a ditribution of beak sizes which were smaller. Over many generations, this can potentially shift the population to a size distribution outside the original range! If two populations undergo a different line of evolutionary change long enough, they will no longer be able (or willing) to interbred. Then they are considered different species. Normally, this requires a series of evolutionary changes over time, not just one or two. Often a specific change in reproduction or mating behavior will occur to result in what is called an isolating mechanism. The songbird example I gave is a case in point. gamila wrote: I asked you to explain why animals that are different can interbred. Can you answer my question now?
no idea but the problem may not be with the animals but be with the classificatory system used which is based on an essentialism
You mentioned bactrian and dromardry camels. Do they look different? Yes. What possible explanation is there for their ability to interbred? There is only one. They have a Common Ancestor. Why do they look different now? Evolution. Natural Selection is one mechanism of evolution, and others (such as genetic drift) could also be part of that mechanism for evolutionary change from their common ancestor.
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by gamila » Sat Aug 29, 2009 3:34 am
Let's look at how Darwin defined Natural Selection (paraphrasing)
the definition of ns is very clear it is very clear from this site It is the process by which heritable traits that increase an organism’s chances of survival and reproduction are favoured than less beneficial traits. Originally proposed by Charles Darwin, natural selection is the process that results in the evolution of organism
and as has been pointed out if a trait appears in an off spring which is not present in its parents then that shows ns is wrong as ns is about traits already present i being passed on because ns is
What possible explanation is there for their ability to interbred?
fact is they do interbreed which should mean they are the same speciies but they are not the same species thus a contradiction
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