We travel around the US with a team of men and women targeting places where we know we'll find sinners. We knew we would find some church going Christians but what we found was shocking. It wasn't the heathen at these wicked evil events. It was the entire church! Please pray for us as we go out to go find those that have gone astray.
Vera, I've been reading these articles. The authors do not find it odd that flightlessness might evolve multiple times among the ratites, but they seem to feel that evolution (a "chance" process, as they repeatedly insist) would converge, over and over, on the same basic body design (long neck, long legs, squat body, etc.).
At this point, I wish to insist, again, that natural selection is not a "chance" process. That's not my explanation for the convergence; it's just that the authors seem way more eager to associate "chance" with "natural selection" than is entirely honest.
Let's take a brief digression, from natural selection of birds, to artificial selection of mammals. Darwin noted, in the 19th century, that almost every domestic mammal species had, at least in some breeds, certain traits not found in their wild counterparts, like floppy ears and spotted coats. It does not seem like the sort of thing breeders would particularly want in, say, cows or pigs; it seems to be a side effect of domestication itself.
In the 20th century, the Russian scientist Dmitri Belyaev spent 50 years trying to breed a tame silver fox (the fur of these foxes is valuable; being able to ranch-breed them would be profitable for Russia). By selecting only for the animals that were most willing to be around humans, he ended up with foxes much tamer and friendlier than wild foxes, but he also ended up with foxes that were no longer silver-grey, but mottled black and white, with floppy ears and upturned tails like dogs.
This apparently is an effect of what is called paedomorphosis: selection for traits (in this case, curiosity and openness to other species) that are found in young animals. The color pattern, folded ears, and upright tail are likewise patterns of embryonic or baby mammals, preserved into adulthood in these tame foxes. Note that the same process (artificial selection for tameness) produced the same effects in species as distinct as dogs, foxes, cows, and pigs.
When we were arguing over whale evolution, I pointed out that turning a nose into a blowhole is basically just a matter of changing the rate of development of different parts of the skull. Many changes in anatomy are likewise the result of altering developmental rates of different parts of the body.
This seems to be the case in flightless ratites: the small, non-flying wings are an example of an embryonic or baby trait preserved into adulthood. The other changes to the body's shape are likewise effects of this change in developmental rates: many of the differences between flightless ratites and other birds are examples of juvenile body forms retained into adulthood.
The point is that these evolutionary changes are neither "chance" nor unrelated to one another: the change to flightlessness played a big part in causing, directly, the other changes.
At this point, I wish to insist, again, that natural selection is not a "chance" process. That's not my explanation for the convergence; it's just that the authors seem way more eager to associate "chance" with "natural selection" than is entirely honest.
In a naturalistic model, it is all chance. How you can deny this is beyond me. Do you believe that God Almighty is orchestrating and inventing these things or not?
This apparently is an effect of what is called paedomorphosis:
Floppy ears is hardy the same as a change in respiration, which I have gone over with you as well. Neonates are acclimating to a new environment. Micro changes in respiration are not easily rectified unless you place Someone behind the wheel of these events monitoring and changing those things DNA changes per His will. We, meaning myself and other Christians that hold to the truth per nature, are not discounting the facts or the obvious connection. It is clear that old designs were used and new coding was added to produce new species.
The entire point of the flightless bird is that this was repeated several times over oceans apart.
vera, I'd like to thank you for a thoughtful and informed answer to my post.
And as soon as you come up with one, I will.
I must confess that I'm not sure what you mean by "chance." I was assuming that it meant the same thing as "random," a term that is actually used in evolutionary theory. Natural selection is not "random."
As for respiration, I don't recall that we were discussing that: we were discussing why ratites that evolved flightlessness on different continents would converge on the same body plan. My answer to that was that flightlessness was accomplished by retaining juvenile features into adulthood in all these species, with similar effects on other aspects of body morphology. This is exactly on a par with floppy ears and spots as common changes in a host of domestic mammals.
Now, if you want to discuss changes in respiration, you will have to stop taking refuge in irrelevancies, such as the fact that many mutations will be detrimental. As I've pointed out many times, most offspring, in every species except our own (and many offspring even in our own) don't survive to have offspring of their own. Harmful mutations are disasters to the individual affected, but irrelevant to the species as a whole, as there are plenty of individuals without that harmful mutation to take up the slack and produce the next generation of (mostly) healthy individuals. Thus the fact that in each generation, only a few, mostly better-adapted, individuals produce the next generation will eliminate the multitude of harmful mutations and preserve a significant fraction of the much rarer beneficial mutations.
I cannot think of a way to make this clearer to you ... for which, perhaps, you will be grateful.
vera, I'd like to thank you for a thoughtful and informed answer to my post.
And as soon as you come up with one, I will.
Hardy hardy
Chance involved probability. What are the statistical odds that three different kinds of flightless birds would evolve on three different continents in three completely different ecosystems and natural parameters?
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Vera, I've been reading these articles. The authors do not find it odd that flightlessness might evolve multiple times among the ratites, but they seem to feel that evolution (a "chance" process, as they repeatedly insist) would converge, over and over, on the same basic body design (long neck, long legs, squat body, etc.).
At this point, I wish to insist, again, that natural selection is not a "chance" process. That's not my explanation for the convergence; it's just that the authors seem way more eager to associate "chance" with "natural selection" than is entirely honest.
Let's take a brief digression, from natural selection of birds, to artificial selection of mammals. Darwin noted, in the 19th century, that almost every domestic mammal species had, at least in some breeds, certain traits not found in their wild counterparts, like floppy ears and spotted coats. It does not seem like the sort of thing breeders would particularly want in, say, cows or pigs; it seems to be a side effect of domestication itself.
In the 20th century, the Russian scientist Dmitri Belyaev spent 50 years trying to breed a tame silver fox (the fur of these foxes is valuable; being able to ranch-breed them would be profitable for Russia). By selecting only for the animals that were most willing to be around humans, he ended up with foxes much tamer and friendlier than wild foxes, but he also ended up with foxes that were no longer silver-grey, but mottled black and white, with floppy ears and upturned tails like dogs.
This apparently is an effect of what is called paedomorphosis: selection for traits (in this case, curiosity and openness to other species) that are found in young animals. The color pattern, folded ears, and upright tail are likewise patterns of embryonic or baby mammals, preserved into adulthood in these tame foxes. Note that the same process (artificial selection for tameness) produced the same effects in species as distinct as dogs, foxes, cows, and pigs.
When we were arguing over whale evolution, I pointed out that turning a nose into a blowhole is basically just a matter of changing the rate of development of different parts of the skull. Many changes in anatomy are likewise the result of altering developmental rates of different parts of the body.
This seems to be the case in flightless ratites: the small, non-flying wings are an example of an embryonic or baby trait preserved into adulthood. The other changes to the body's shape are likewise effects of this change in developmental rates: many of the differences between flightless ratites and other birds are examples of juvenile body forms retained into adulthood.
The point is that these evolutionary changes are neither "chance" nor unrelated to one another: the change to flightlessness played a big part in causing, directly, the other changes.
At this point, I wish to insist, again, that natural selection is not a "chance" process. That's not my explanation for the convergence; it's just that the authors seem way more eager to associate "chance" with "natural selection" than is entirely honest.
In a naturalistic model, it is all chance. How you can deny this is beyond me. Do you believe that God Almighty is orchestrating and inventing these things or not?
This apparently is an effect of what is called paedomorphosis:
Floppy ears is hardy the same as a change in respiration, which I have gone over with you as well. Neonates are acclimating to a new environment. Micro changes in respiration are not easily rectified unless you place Someone behind the wheel of these events monitoring and changing those things DNA changes per His will. We, meaning myself and other Christians that hold to the truth per nature, are not discounting the facts or the obvious connection. It is clear that old designs were used and new coding was added to produce new species.
The entire point of the flightless bird is that this was repeated several times over oceans apart.
Vera
vera, I'd like to thank you for a thoughtful and informed answer to my post.
And as soon as you come up with one, I will.
I must confess that I'm not sure what you mean by "chance." I was assuming that it meant the same thing as "random," a term that is actually used in evolutionary theory. Natural selection is not "random."
As for respiration, I don't recall that we were discussing that: we were discussing why ratites that evolved flightlessness on different continents would converge on the same body plan. My answer to that was that flightlessness was accomplished by retaining juvenile features into adulthood in all these species, with similar effects on other aspects of body morphology. This is exactly on a par with floppy ears and spots as common changes in a host of domestic mammals.
Now, if you want to discuss changes in respiration, you will have to stop taking refuge in irrelevancies, such as the fact that many mutations will be detrimental. As I've pointed out many times, most offspring, in every species except our own (and many offspring even in our own) don't survive to have offspring of their own. Harmful mutations are disasters to the individual affected, but irrelevant to the species as a whole, as there are plenty of individuals without that harmful mutation to take up the slack and produce the next generation of (mostly) healthy individuals. Thus the fact that in each generation, only a few, mostly better-adapted, individuals produce the next generation will eliminate the multitude of harmful mutations and preserve a significant fraction of the much rarer beneficial mutations.
I cannot think of a way to make this clearer to you ... for which, perhaps, you will be grateful.
vera, I'd like to thank you for a thoughtful and informed answer to my post.
And as soon as you come up with one, I will.
Hardy hardy
Chance involved probability. What are the statistical odds that three different kinds of flightless birds would evolve on three different continents in three completely different ecosystems and natural parameters?
Vera
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