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shropshire

Origin of the species, where do you stand?

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>a fish with gills to a land animal with functional lungs . . .

One misconception about evolution is that, at some point, a fish just "got lungs" somehow and started walking. Evolution doesn't work like that. Lungs were never 'created' - they were adapted from something else.

In the case of fish, it was likely that lungs came from a part of its stomach. Early fish had pretty simple GI tracts - just heavily-vascularized passages with pouches for the stomach and intestinal areas. Worked OK but was not ideal.

Now, when these fish got caught in stagnant pools they normally just died; there's not enough oxygen in that sort of water to sustain them. But some fish figured out that "gulping" air through their gills let them live a little longer. (This likely started when a fish with poor aim tried to eat algae off the surface.) They survived a bit longer than their companions, and the gulping behavior became part of the fish's inherited behavior. (BTW many fish still do this today.)

Well, that gulping also resulted in air into its GI tract, which was a problem - it made the fish float, which is suboptimal for a creature that has to dive to escape predators. But not asphyxiating made up for the problem.

Then a chance mutation provided a pouch in the top of the stomach. Nothing new; the GI tract already had a few pouches in it. But the fish could now swallow air and it would just stay in the pouch. Since it could keep a small bubble in that pouch, its bouyancy wouldn't change with time; it could stay submerged. At the same time, keeping a little pocket of air inside that pouch (which, like the stomach, was heavily vascularized) helped keep the fish from asphyxiating. This was huge, and soon all fish had that mutation.

Thus the lung was born. No radically new genetic information, just a change in one instruction that said "make 1 2 pouches right here." The first lungs sucked; the fish surely relied on its gills 99% of the time. But that 1% of the time meant life or death for those fish, so the trait was kept.

As the years went by, random mutations tweaked the lung a bit more. It got a better opening into it, so the fish could eat and swallow air and not mix the two as often. Blood vessel concentration increased. Musculature changed so the fish could more easily get air into the pouch. Since these fish survived better than their less-adapted companions, the traits were selected for.

Then another remarkable thing happened - some fish started re-using the primitive lung for something else! Fish that did NOT need to breathe air (i.e. ocean and lake fish) started closing off the new pouch, and using those blood vessels to both absorb and emit gas into the pouch. This let the fish regulate its buoyancy without gulping air. This was another huge benefit for fish - they could expend much less effort swimming, and thus save their calories for things like mating and reproduction. And again, no new structures. No sudden appearance of a swim bladder. Just an adaptation of existing structures.

At the same time, some fish started sticking to the stagnant puddles because now they could breathe air. Like mudskippers, they realized they could use their fins to hop around. And at that time there were NO other animals on land! No predators! They were safe! There was food the other fish couldn't get to! That was such a huge advantage that the fish that could survive on land for longer periods survived far more readily than the ones who couldn't.

And again, with no new creations of legs or lungs, you now had fish and land animals.

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What new information is added? The basic life processes are the same. The DNA components are the same. They each live in an environment to which they are adapted.



There's more to it than that. Speciation driven by natural selection is not the same nor can it lead to macro-level evolution. All of the instructions to form a living thing the way it is and to gradually change in different directions (e.g. grow longer/shorter hair or lighter/darker skin) due to environmental input is included in its DNA. In order for it to change (even gradually) into something completely different (e.g. fish to the next random level ultimately leading to man) there must be instruction to do so.



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There are fish now that can breathe air, and frogs go from being water-breathing tadpoles to air-breathing frogs.



Whatever design features they have came from information which was already included in their genes. Evolution cannot be built on a loss of specificity which is what occurs over time.

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>Whatever design features they have came from information
>which was already included in their genes.

. . . or in a slightly modified (i.e. mutated) version of their genes. That's all that's required for evolution - very small changes over billions of years. It only takes one mutation of one genetic instruction to give a fish a very, very primitive lung, using instructions that are already there for making stomachs. The next mutation might take a thousand years - now you have a very slightly better lung. After a thousand of these thousand-year periods you have a basic lung - and you still have a thousand more chances to make that lung.

Yet none of those fish ever got the "here's how to make a lung" gene sequence. They just adapted the stuff that's already there in their genome to new purposes.

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There's more to it than that. Speciation driven by natural selection is not the same nor can it lead to macro-level evolution. All of the instructions to form a living thing the way it is and to gradually change in different directions (e.g. grow longer/shorter hair or lighter/darker skin) due to environmental input is included in its DNA. In order for it to change (even gradually) into something completely different (e.g. fish to the next random level ultimately leading to man) there must be instruction to do so.

Why not? Because you believe that? If so, well, then we'll have to disagree. If other people agree that "God must have done it because we just don't believe it would have happened on its own" then I'll have to disagree with them as well.

Are the horse and the donkey different or the same species to you?

Wendy W.
There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)

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I see. Since you (general reference to creationists, not you specifically) don't understand it, it can't possibly be true.



You're starting to sound like kallend... Everyone else has to prove their points, but all of your's are self evident?



It's a trick I learned from mnealtx and rushmc;)
...

The only sure way to survive a canopy collision is not to have one.

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Are the horse and the donkey different or the same species to you?



Donkeys, horses, and zebras readily hybridize with each other. They and their offspring (mule, hinny, zorse, zeedonk, zonkey, zebras) would appear to come from a common ancestor (variation within a kind).

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So is it the abilitiy to hybridize or just the general appearance that makes them "variation within a kind" as opposed to species?

Wendy W.
There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)

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They go back to Eohippus

http://www.talkorigins.org/faqs/horses/eohippus_equus.html

In their attacks on evolution, creationists sometimes claim that the evolutionary family tree of the horse is flawed. And while this statement is hardly surprising given the source, some creationists also claim that the remains of Hyracotherium, the animal at the base of the horse sequence and more popularly known as eohippus, have been found along side the remains of modern horses. This is hardly a problem for any modern theory of evolution, which allow ancestor and descendant species to exist side by side, but I have never heard the assertion from other than creationist or new age sources.

No where is there found a fossil of Hyracotherium found along side Equus nevadensis, and so it would seem that my first guess about Rimmer's claim was correct. Because fossil Equus had been found, he felt that they had to have lived along side Hyracotherium. But Rimmer was unaware that this shows nothing of the kind, and instead here veals a profound misunderstanding of geology. Later writers who used him as a source assumed that Hyracotherium and Equus had been found in the same strata.



BUT
Then you have people like this website that still maintain the falshood that Rimmer put out in 1935


Horses have not evolved, they were created by God on Day 6.

http://www.angelfire.com/mi/dinosaurs/horse.html


But remember when they do hybridize many end up sterile and they can no longer pass on their DNA

Is that gods plan??

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>Donkeys, horses, and zebras readily hybridize with each other. They
>and their offspring (mule, hinny, zorse, zeedonk, zonkey, zebras) would
>appear to come from a common ancestor . . .

Yes, right! They have diverged far enough that their offspring is no longer fertile (mules are sterile) but can still usually produce offspring. However, we know that genetic drift is continuing in horses/donkeys/zebras, and eventually these species will no longer be able to hybridize.

So here we have similar species which are diverging from a common ancestor. The equine fossil trail is one of the most complete around, and we can see this trend continuing back for several million years. We can even see the same sort of divergence happening in the fossil record:

Ancestor:

Hyracotherium (55 million years ago)
|-Pachynolophus
|-Propalaeotherium
|-Orohippus
....|-Epihippus
.........|-Mesohippus
............|-Miohippus
...............|-Anchitherium
...............|-Archeohippus
...............|-Parahippus
...................|-Pseudhipparion
...................|-Calippus
...................|-Dinohippus
.......................|-Hippidion
.......................|-Equus (modern horse species)

(sorry about the cruddy chart)

What's cool about the horse fossil progression is how complete it is. There are multiple examples of most of the above, with strong correlation between comparative anatomy and age.

One thing I've never understood about traditional creationism is - where do fossil lineages like this fit in? Is God really trying to mess with people by planting such a rich and consistent history of fake fossils? Did he create Epihippus, let it exist a few million years, then kill it off and create Mesohippus, which is remarkably similar? Seems like odd behavior.

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I don't know about anyone else, but for me the last few pages of posts from Billvon are exactly what make this forum worth reading.

The patience to address all opposing points with elegant answers that are clear, concise, brilliantly illustrated and obviously backed up with a strong body of knowledge.

Me, I'm just an antagonistic bastard - Billvon is a class act and we are lucky to have him:)
Do you want to have an ideagasm?

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A few transitional fossils that show the transition from reptile to mammal:

All of your following names and ages tell me nothing, and honestly, I doubt if they mean anything to you.

So now, you are telling me that I evolved from a reptile.

I thought that it was stated earlier that we didn't even evolve from apes. We only had a common ancestor. Was that a hairy crocidile?

Do you believe that any species had held the line against radical change through the eons?

If there is one, there must be others. Some things are what they are.

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All of your following names and ages tell me nothing,




Uh have you ever thought about taking a class in paleontology....some of that MIGHT just make sence...:D



And genetics and molecular biology and animal husbandry.

It truly amazes me that the naysayers believe that there's some kind of grand conspiracy among scientists in so many different fields to promote evolutionary biology.

WHEAT is an example of a species that first appears within the human timeframe.

If an "intelligent designer" created humans, why do we have spinal columns better adapted for going on all fours, why do we have an appendix, why are we susceptible to cancer...?
...

The only sure way to survive a canopy collision is not to have one.

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I don't know about anyone else, but for me the last few pages of posts from Billvon are exactly what make this forum worth reading.

The patience to address all opposing points with elegant answers that are clear, concise, brilliantly illustrated and obviously backed up with a strong body of knowledge.

Maybe I'm not so easily impressed.

I've heard that a mouse can become an elephant, and a reptile can become a mammal.

Sorry, but I should be able to look out my door and see animals in all stages of transition from one species to another, and from one genus to another. After all, nature, or would that be mother nature, has had millions, or is it billions of years to put the whole thing into motion.

It just ain't happenin'.

I want to see proof in hand, kind of like atheists want to see proof of God.

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I don't know about anyone else, but for me the last few pages of posts from Billvon are exactly what make this forum worth reading.

The patience to address all opposing points with elegant answers that are clear, concise, brilliantly illustrated and obviously backed up with a strong body of knowledge.

Maybe I'm not so easily impressed.

I've heard that a mouse can become an elephant, and a reptile can become a mammal.

Sorry, but I should be able to look out my door and see animals in all stages of transition from one species to another, and from one genus to another. After all, nature, or would that be mother nature, has had millions, or is it billions of years to put the whole thing into motion.

It just ain't happenin'.

I want to see proof in hand, kind of like atheists want to see proof of God.



You look out of your door and see animals and plants. How do YOU know if they're in transition or not? There's no possible way YOU can conclude that they are not in transition.
...

The only sure way to survive a canopy collision is not to have one.

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Sorry, but I should be able to look out my door and see animals in all stages of transition from one species to another, and from one genus to another. After all, nature, or would that be mother nature, has had millions, or is it billions of years to put the whole thing into motion.



Oh for Fu... You can!!! (And have been told so before)

Obviously the reason you aren't impressed by Billvon's posts is because you haven't bothered to read them. Flying squirrels, mudskippers, flightless birds, hippopotamii - all in transition from one stage to the next. And these are just the obvious ones.

If you're thinking one day you should be able to see a flying squirrel give birth to offspring that are birds then you are still a long way from understanding the basics of the theory.
Do you want to have an ideagasm?

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Well, actually, we _all_ have a common ancestor, from humans to chimpanzees to chickens to oak trees. We know this because we all use the same basic life processes - expression of genetic traits through DNA conservation and recombination, basic respiration, cell membrane construction, basic cell structure similarity etc. And the differences between each organism are directly linked to how much time they've spent apart from each other.

So, are you stating that all life began at a moment in time. If so , obviously there was a catalyst of sorts. For lack of a better word, shall we call it creation?

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Sorry, but I should be able to look out my door and see animals in all stages of transition from one species to another, and from one genus to another.

I think you ARE seeing animals in various stages of transition from one species to another. It's just infrequent that changes occur fast enough for you to see them in one lifetime. Of course there were those moths back in early industrial times that changed from white to black to white again....remember those?

linz
--
A conservative is just a liberal who's been mugged. A liberal is just a conservative who's been to jail

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Obviously the reason you aren't impressed by Billvon's posts is because you haven't bothered to read them. Flying squirrels,

First off, flying squirrel is only a name. They are actually gliding squirrels.

Now, let me take that mentality to its logical conclusion.

If I jump out of an airplane without a shirt on enough times then the skin under my arms should become loose and floppy, and if I breed a bunch of women, one my offspring should come out with very loose skin under his or her arms.


After several generations wing suits will not be needed.
From there, by the logic of Billvon's evolutionary theory, eventually feathers will begin to develop. Soon, my offspring wouldn't even need a parachute.

Am I on the right track. Go evolution!!

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You look out of your door and see animals and plants. How do YOU know if they're in transition or not? There's no possible way YOU can conclude that they are not in transition.

And, you can't prove that they are. Sounds like and impasse to me.

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You look out of your door and see animals and plants. How do YOU know if they're in transition or not? There's no possible way YOU can conclude that they are not in transition.

And, you can't prove that they are. Sounds like and impasse to me.



YOU choose not to look at the evidence which is why YOU don't see it. YOU choose to misinterpret the science, over and over, even when the patient Billvon explains it to you. Your arguments are just silly and ignorant, not scientific rebuttals.
...

The only sure way to survive a canopy collision is not to have one.

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