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Evolution is a FACT!!!!

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gluadys

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Maybe it's my own faith that is blinding me to what is supposed to be factual evidence here, but just because animals have similar traits or bone structures doesn't mean that you can piece together this tree of how they evolved. That may be a starting point if you were going to investigate, because for the theory to be true you would expect the similarities. But I expect similarities also due to a common designer (I know you've heard that one a million times).

I would say it is your own misconceptions of what to expect from evolution that is more of a problem than your faith.

When do you expect similarities? You claim common design as a source of similarities. Actually, there is no obligation on a common designer to re-use similar elements of design. So this is not a scientific prediction. You cannot predict that because the same designer created animal A and animal B that they will have any common elements. They could be entirely novel and different.

Of course, a designer may choose to re-use common motifs, so design does not eliminate similarities either. But the main point is that since re-use of common elements in design is optional, the pattern of similarity is unpredictable.

Is there another source of similarity? Yes, genetic inheritance. I expect you will agree that children are more genetically similar (and often more visibly similar) to their parents and their siblings than to those to whom they are not so directly related.

Now, what is the principle difference between similarity through design and similarity through genetic inheritance? Similarity through genetic inheritance is predictable on a statistical basis. You may not be able to predict which children will have blue eyes in a family where Mum has blue eyes and Dad has brown eyes. But you can predict the probability that each child will have blue eyes. And on a population-wide basis, you can predict the proportion of blue-to-brown eyes.

Design permits similarities, but does not require them. Nor does it require similarities to fall into a predictable pattern. Genetic inheritance requires similarities and requires that the similarities fall into the pattern we associate with a geneology or family tree.

Which pattern of similarity do we find in nature? Do we find the modular pattern of similarities which can be organized in multiple ways as we would expect from design, or a single pattern of similarities organized on the principle of genetic inheritance?

It would seem that if God chose to design each species (or each group of species), he chose a pattern of design that is identical to the pattern required of and predicted by genetic inheritance. Can you then blame scientists for finding that pattern and attributing it to genetic inheritance?

There are just so many systems, body plans, mechanisms and so forth that need to change from one kind to another (say fish to reptile to bird) that you can't just look at one similar bone structure and expect that all the other things just happened.

And this is what makes the phylogenetic tree such a powerful support for the theory of evolution. Because it doesn't matter whether you are looking at leg bones, ear bones, nerve arrangements, hearts, viral insertions or mutations: they all point to the same genetic tree. If design were the principal reason for similarity, it would be feasible to have one pattern of similarity for jawbones and an entirely different pattern of similarity for limb arrangements and a different one again for blood types. We would expect to get different organizational trees for each module. But we don't. We get basically the same tree no matter what characteristic we begin with. Evolution explains why we do. Common design does not.

Each stage would have to be strong enough to survive for quite a while until the next little beneficial thing happened, that a perfectly species would have to get to a failing state before becoming something that works again.

A species that is going to survive through a transition stage that takes many generations to complete cannot be in a "failing state" at any point in the transition. This is a version of the "what good is half a wing?" argument. In fact, half a wing can be an advantage over no wing. It may not be capable of supporting powered flight yet, but it can be useful for other purposes. In evolution a "failing state" is not a possible state for a transitional species.

Those in-between stages are what I have not seen. The freaks if you will.

This is why I said it is your expectations of evolution that seem to be the problem. Freaks are generally individuals outside the normal range of species variation. Evolution depends on more subtle variations becoming established through a large segment of the population as freakish characteristics seldom do. There is no reason transitional species should be obvious freaks.

At whatever point you look at these creatures along the evolutionary tree, they appear to be fully functional and formed, and yes, may look like other creatures but are perfect in their own species.

And that is what evolution is supposed to look like.

I just don't see everything changing at the same pace in sync with every other change to the point where you wouldn't notice that it was a freak

Why not? Suppose a change in environmental conditions or female sexual preference favors a particular animal having a longer neck. So generation after generation, the average neck length becomes longer. Now, suppose the longer neck works better with longer legs. Then the longer-necked animals with longer legs have an advantage over longer-necked animals with shorter legs.

IOW, when looking at the two sets of characteristics, you get four groups in the population.

1. short necks and short legs (not favoured)
2. short necks and longer legs (same as above, as leg length is irrelevant when the neck is short)
3. longer necks and short legs (favored over 1 & 2)
4. longer necks and longer legs (favored over 1, 2 & 3)

Similarly, if a change in the formation of a jaw bone also favours a change in its muscle attachment, both will evolve together. There is no need for evolution to depend on freakish arrangements.
 
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kevin36

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The word "evolution" can be used in 2 way, and there should really be 2 different words to avoid the confusion. Evolution is both a fact and a theory depending on how you use the word.

First I must clarify what a theory is. Many ppl think that theory is somewhat less then a fact, that once a theory is proven it becomes a fact. This couldn't be farther from the truth. Facts are observable things around us, and a theory is how we explain those things. Like the fact that gravity exists, that's an observable fact. But what causes it? The theory of relativity is the best explanation thus far for gravity. A theory can be even more important then the fact. We know that we are affected by gravity (fact), but it's understanding how and why (theory) that really helps us learn.

In reguards to evolution, it is a fact that life on earth has evolved. As we go deeper and deeper into the layers of strata within the earth, we see changes in the life forms that existed. Entirely new sets of ecosystems existed in the past. It is a fact that we evolved.

The theory of evolution is how we try to explain that fact. Darwin had the idea of phyletic gradualism. (Although it may have been he expected more our current models, but that's another topic). Currently our understanding of evolution leads us to believe in punctuated equilibrium. All the mechanisms for this to have happened are observed in nature today, and they happen even faster then the fossil record requires.

I saw some threads about the use of the word "theory" so I hope this clears some things up.


No, it's a fact that life on Earth has, and continues to, adapt- it adjusts according to it's environment (except for man, who adapts his environment to suit his own needs). By most people's understanding, "evolution" means that one species has progressed into another, no matter the semantics of what "theory" and "evolution" mean according to the dictionary.

Evolution as it is commonly understood hasn't happened, nor has science been able to prove it- thus the term "theory", and unproven hypothesis, being applied to the notion.

The Bible states that each animal was created after it's own kind. If that's true, there's no need for evolution, which implies that God's creation is imperfect or incomplete.

Oh, and as far as the theory of relativity... Einstein was the most foolish smart guy to come around in a long time.

Kevin
 
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kevin36

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Unlike most creationists, God is NOT simple.


Wow.

Hey, I know I'm new here, but I thought I was in a Christian part of this site... guess I was wrong.

I've never liked name-calling and stuborn refusals to even listen to the other guys point of view, so maybe I'll stop trying to read and discuss logically on this string and go somewhere else.

God Bless you all anyway...
Kevin
 
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random_guy

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No, it's a fact that life on Earth has, and continues to, adapt- it adjusts according to it's environment (except for man, who adapts his environment to suit his own needs). By most people's understanding, "evolution" means that one species has progressed into another, no matter the semantics of what "theory" and "evolution" mean according to the dictionary.

I don't know about you, but I don't use layman's terms and definitions when discussing science, I use the science version and terms. As such, evolution is a fact, and the theory explains why it happens. Of course, you're free to use the dictionary, but don't expect any scientist to take you seriously.
Evolution as it is commonly understood hasn't happened, nor has science been able to prove it- thus the term "theory", and unproven hypothesis, being applied to the notion.

And here, you show how you misunderstand science. You can't prove things in science, proofs are for math and alcohol. Evolution has happened, as evidenced through observation in the lab, the wild, and throughout the fossil record. It doesn't matter how loudly you may deny it, I would definitely trust the consensus of scientists that spend their lives studying to some one that doesn't understand the scientific method.
The Bible states that each animal was created after it's own kind. If that's true, there's no need for evolution, which implies that God's creation is imperfect or incomplete.

That's your interpretation. Also, whether you like it or not, Creationists require evolution, also. And not just any evolution, but a hyper-evolution to account for the diversity of life after a global flood.
Oh, and as far as the theory of relativity... Einstein was the most foolish smart guy to come around in a long time.

Kevin

Yeah, I can guarentee Einstein understand science, unlike most Creationists. He showed that the current Law of Gravity was incorrect through the scientific method, not through politics like Creationists do.
 
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kevin36

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Scientists love to use the scientific method, which is fine for talking and relating to other scientists, but what I said (and I think that you missed this) is how you need to understand how the other people you talk to understand what you say.

It's like reading the Bible- you have to understand the society of both the writer and his audience to truely understand what is being said. Languages change, and to read the bible with only 21st century understanding of the wording, you loose much of the meaning, or misunderstand it completely.

Likewise, you can go on all day long about what "theory" and "evolution" actually mean, but what you need to consider is what that means to the person that you are talking to- what HE understands you to be saying. Unless you do that, you might as well be talking to the wall, because neithe one of you is understanding the other.

By the commonly understood meaning of the word "evolution", your science has not yet proved that it has happened, nor will it. On the other hand, adaptation is easily witnessed.

Show me one species that you can empirically prove has descended from a seperate species, and I'll leave you alone, but as of yet no body has ever been able to do it. Al they can do is say we "think" this has happened, or that they're "pretty sure", or "evidence suggests". Scientists love proofs, but here they're strangely absent.

Hense... theory.

Kevin
 
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Jase

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Scientists love to use the scientific method, which is fine for talking and relating to other scientists, but what I said (and I think that you missed this) is how you need to understand how the other people you talk to understand what you say.

It's like reading the Bible- you have to understand the society of both the writer and his audience to truely understand what is being said. Languages change, and to read the bible with only 21st century understanding of the wording, you loose much of the meaning, or misunderstand it completely.

Likewise, you can go on all day long about what "theory" and "evolution" actually mean, but what you need to consider is what that means to the person that you are talking to- what HE understands you to be saying. Unless you do that, you might as well be talking to the wall, because neithe one of you is understanding the other.

By the commonly understood meaning of the word "evolution", your science has not yet proved that it has happened, nor will it. On the other hand, adaptation is easily witnessed.

Show me one species that you can empirically prove has descended from a seperate species, and I'll leave you alone, but as of yet no body has ever been able to do it. Al they can do is say we "think" this has happened, or that they're "pretty sure", or "evidence suggests". Scientists love proofs, but here they're strangely absent.

Hense... theory.

Kevin
Hmm, one of the arguments creationists shouldn't use. Something being a theory doesn't mean it's wrong. Did you know that Gravity is "just a theory"? But you are quite confident that that is true when you drop a hammer on your foot.
 
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Smidlee

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Facts are observable things around us, and a theory is how we explain those things. Like the fact that gravity exists, that's an observable fact.
If you mean by gravity the force that pulls you to the ground then yes , gravity is a fact just like if all you mean by evolution is things change then no doubt things change rather for good or bad.

Yet gravity is a sorry comparison to evolution as it shows just how bad evolution theory is. Gravity is extremely predictable with very little surprises compare to the total unpredictability to living things. It's very common in the last years to find articles where scientist were totally surprise of the results found in their biology studies.

If what you mean by evolution is "mutation creation" then this is far from being fact. This is a belief which I have no faith in.
 
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gluadys

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By the commonly understood meaning of the word "evolution", your science has not yet proved that it has happened, nor will it. On the other hand, adaptation is easily witnessed.

Yes, adaptation is easily witnessed. But a scientist will want to explain how it happens. The theory of evolution explains adaptation. Without evolution, what explains adaptation? How do species adapt to new situations without evolving?

Show me one species that you can empirically prove has descended from a seperate species, and I'll leave you alone, but as of yet no body has ever been able to do it. Al they can do is say we "think" this has happened, or that they're "pretty sure", or "evidence suggests". Scientists love proofs, but here they're strangely absent.

Hense... theory.

Kevin

Check out this report of an experiment in raising fruit flies in different environments. (Note that this is not about radiating them to produce mutations. Nothing was done to the fruit flies except give them different habitats to live in.)

G Kilias, SN Alahiotis, and M Pelecanos. A multifactorial genetic investigation of speciation theory using drosophila melanogaster Evolution 34:730-737, 1980.

http://links.jstor.org/sici?sici=0014-3820(198007)34:4<730:AMGIOS>2.0.CO;2-J

The result of this experiment was the production of new species, some more radically different from the parent population than humans are from chimpanzees.

In nature we see a similar situation in the Faroe house mice, first introduced to the islands from Europe about 250 years ago. As they spread to different habitats on the islands they developed into six different species.
 
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kevin36

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Yes, adaptation is easily witnessed. But a scientist will want to explain how it happens. The theory of evolution explains adaptation. Without evolution, what explains adaptation? How do species adapt to new situations without evolving?



Check out this report of an experiment in raising fruit flies in different environments. (Note that this is not about radiating them to produce mutations. Nothing was done to the fruit flies except give them different habitats to live in.)

G Kilias, SN Alahiotis, and M Pelecanos. A multifactorial genetic investigation of speciation theory using drosophila melanogaster Evolution 34:730-737, 1980.

http://links.jstor.org/sici?sici=0014-3820(198007)34:4<730:AMGIOS>2.0.CO;2-J

The result of this experiment was the production of new species, some more radically different from the parent population than humans are from chimpanzees.

In nature we see a similar situation in the Faroe house mice, first introduced to the islands from Europe about 250 years ago. As they spread to different habitats on the islands they developed into six different species.

Adaptation- to me, anyway- is a change within a species to better conform to it's (possibly new or changing) environment. The fruit fly example you gave is excellent proof of this, and I will never argue against it.

What I do argue against, and what is the primary problem of the theory of evolution, is not that it takes adaptation into account, but that it takes it so far as to say that one species or type of animal slowly becomes another over time.

Your fruit fly is still a fruit fly. It has adapted, not evolved (in the full theory of evolution sense).

God Bless
Kevin
 
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EnemyPartyII

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Adaptation- to me, anyway- is a change within a species to better conform to it's (possibly new or changing) environment. The fruit fly example you gave is excellent proof of this, and I will never argue against it.

What I do argue against, and what is the primary problem of the theory of evolution, is not that it takes adaptation into account, but that it takes it so far as to say that one species or type of animal slowly becomes another over time.

Your fruit fly is still a fruit fly. It has adapted, not evolved (in the full theory of evolution sense).

God Bless
Kevin
Kevin, are you familiar with "ring species"?

Cases where evolution and what you call adaption are pretty clearly shown to be the same thing
 
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EnemyPartyII

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A classic example of ring species is the Larus gulls circumpolar species "ring". The range of these gulls forms a ring around the North Pole. The Herring Gull, which lives primarily in Great Britain, can hybridize with the American Herring Gull (living in North America), which can also interbreed with the Vega or East Siberian Herring Gull, the western subspecies of which, Birula's Gull, can hybridize with Heuglin's gull, which in turn can interbreed with the Siberian Lesser Black-backed Gull (all four of these live across the north of Siberia). The last is the eastern representative of the Lesser Black-backed Gulls back in north-western Europe, including Great Britain. However, the Lesser Black-backed Gulls and Herring Gull are sufficiently different that they cannot interbreed; thus the group of gulls forms a continuum except in Europe where the two lineages meet. A recent genetic study has shown that this example is far more complicated than presented here (Liebers et al, 2004).

 
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kevin36

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Kevin, are you familiar with "ring species"?

Cases where evolution and what you call adaption are pretty clearly shown to be the same thing


No, I can't say that I'm that up on my terminology on this subject... It's more of a pet-peeve that anything else, really. :)

To me, and no offense intended here, the two terms just sound like an unnecessary muddying of the waters; a blurring of the lines, so to speak. That's just an opinion of a definate non-expert, so take it for what it;s worth... :)

So is a ring species a sort of sub-species, but still the same basic critter?

God Bless
Kevin
 
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random_guy

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Adaptation- to me, anyway- is a change within a species to better conform to it's (possibly new or changing) environment. The fruit fly example you gave is excellent proof of this, and I will never argue against it.

What I do argue against, and what is the primary problem of the theory of evolution, is not that it takes adaptation into account, but that it takes it so far as to say that one species or type of animal slowly becomes another over time.

Your fruit fly is still a fruit fly. It has adapted, not evolved (in the full theory of evolution sense).


God Bless
Kevin

I don't think you understand evolution. In evolution, you don't stop being your original group. That's why we're still apes, mammals, and tetrapods. How much biology have you actually studied, as in from courses and not Creationist websites?
 
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kevin36

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I don't think you understand evolution. In evolution, you don't stop being your original group. That's why we're still apes, mammals, and tetrapods. How much biology have you actually studied, as in from courses and not Creationist websites?


I'm not a biologist, but I don't consider myself an ape, no matter what anybody says.

God made Man seperate from the animals, and for any Christian to say that it took thousands or millions of years for God's "very good" creation- made in His own image- to finally become what He wanted to have a relationship with is both intelectually and morally reprehensible.

So when you speak of evolution, you speak of the process, and not the idea that every animal came from a single original source?

I guess I'm learning that evolution as a process is possibly the same as what I've always known as adaptation, but I'll never swallow the idea that one seperate species is descended or derived from another, or that Man has ever been anything but as He was made by God.

Help me out if I'm wrong...

God Bless
Kevin
 
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Citanul

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I'm not a biologist, but I don't consider myself an ape, no matter what anybody says.

Define what an ape is then. If you go purely by physical characteristics, you'll find that pretty much whatever definition you can come up with, humans also fit that definition.
 
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gluadys

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Adaptation- to me, anyway- is a change within a species to better conform to it's (possibly new or changing) environment.

And the mechanism which produces such adaptation is evolution, right? Or do you know of any other way for a species to adapt.

What I am getting at here is the tendency of some anti-evolutionists to speak of adaptation as excluding evolution. Some will say "I believe species adapt; but I don't believe they evolve."

The point I am keying in on here is that without evolution there is no way for species to adapt. It appears you agree with this. Correct me if I am wrong.

What I do argue against, and what is the primary problem of the theory of evolution, is not that it takes adaptation into account, but that it takes it so far as to say that one species or type of animal slowly becomes another over time.

It is not a problem for evolution at all. It is a problem for those who try to explain the emergence of new species and the relatedness of species while rejecting evolution.

Your fruit fly is still a fruit fly. It has adapted, not evolved (in the full theory of evolution sense).

Did you think "fruit fly" is the designation of a species? Apparently you are unaware that there are hundreds of different species of fruit flies, as different from each other as different species of fish are from each other. They live in separate populations, in different habitats, on different diets, and breed within their own species, but not with others. They have distinctively different DNA patterns. (As I mentioned, one of the new species produced in the experiment showed more divergence from its parent population than humans do from chimpanzees.) A trained entomologist would no more mistake one species of fruit fly for another than a mammalian zoologist would mistake a cheetah for a snow leopard.

Yes the fruit fly is still a fruit fly, but that is equivalent to saying that a human is still an ape.


Your request was:
Show me one species that you can empirically prove has descended from a seperate species,

I have done so, and those more knowledgeable in evolutionary biology can give you hundreds of other examples.

So now you want to claim that you really didn't mean "species", you really meant some larger group such as family (the Linnean rank of "fruit fly"). That's called shifting the goal posts.
 
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gluadys

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So when you speak of evolution, you speak of the process, and not the idea that every animal came from a single original source?

Yes, when biologists speak of the theory of evolution they are referring to the process and the mechanisms (such as mutation and natural selection) by which species change and adapt, whether or not they become new species. So the adaptation of the pepper moth to industrialization (and later its re-adaptation to a cleaner environment) is an example of evolution by natural selection even though there was no species change.

In some situations, when evolution continues over many generations, the accumulation of such changes produces new species.

The proper terminology for the concept that all of today's species came from one or a very few original sources of early life is "universal common descent". It is part of the overall concept of evolution, but only one part of it. It is improper to limit the meaning of evolution to universal common descent.

Some anti-evolution "educational" sources do this to avoid using the term evolution in its more ordinary meaning i.e. species change. A common tactic is to say "adaptation" instead of "evolution" as if they were different processes. But evolution is the process by which species adapt. They can't be separated, so using non-standard terminology is merely a tactic of obfuscation and confusion.

It is probably best to think of evolution as including three aspects: fact, process (or theory) and history.

The fact is that species do change over time. That is the fact of evolution.

The process describes how such change comes about and involves such things as mutation, variation, environmental challenges, differential reproductive success, etc. This whole complex explaining the mechanism or process of species change is the basic theory of evolution. Normally, when scientists refer to "evolution" this is what they are talking about.

Naturally, once we have grasped that species are related to each other much as individuals in a family are related to each other, we become interested in figuring out who is related to whom, in what way, and how far back you can trace the ancestry.

Evolution does not pre-suppose a single origin of life. Theoretically, life could have had several separate origins in special creations (what creationists call the Genesis "kinds"). If this is the case, we should be able to divide species into related groups and show that the groups each exist independently of each other.

But what we get instead is groups within larger groups within still larger groups inside still larger groups, just as a "family reunion" would include a larger and larger group depending on whether you drew the line at all descendants of your grand-father, all descendants of your great-great-grandfather, or all descendants of an ancestor back in the 15th century. And we get no end to it.

All evidence points to a single common origin of all things living on earth today (not just animals, but everything from bacteria to yeast to oak trees to zebras and including humans as part of the great family of living things). We are obviously more closely related to animals than to carrots, but we are related to carrots. And we are more closely related to some animals than to other. Butterflies are more distant relatives than elephants and elephants more distant relatives than gibbons. Our nearest relatives are chimpanzees which are more closely related to us than to other apes such as gorillas or orangutans.

But the consistent pattern of the evidence gathered in tracing species change is that every life form, past as well as present, is related to every other life form. As noted, this pattern was not pre-supposed. It was found to be true by observation. So common descent is not an assumption, but a conclusion from the evidence.

A great web-site for learning about the web of relationships is the Tree of Life project:

http://tolweb.org/tree

To re-cap, common descent is certainly part of what we mean by "evolution". But it is improper to limit the meaning of "evolution" to only common descent. In particular scientific references to evolution usually refer to documentation of species change (the fact of evolution) and/or to the processes which bring about the change (theory of evolution).
 
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EnemyPartyII

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No, I can't say that I'm that up on my terminology on this subject... It's more of a pet-peeve that anything else, really. :)

To me, and no offense intended here, the two terms just sound like an unnecessary muddying of the waters; a blurring of the lines, so to speak. That's just an opinion of a definate non-expert, so take it for what it;s worth... :)

So is a ring species a sort of sub-species, but still the same basic critter?

God Bless
Kevin
No. Thats why the species at the far end of the ring can't breed with its precursor species at the start of the ring... *bump*

A classic example of ring species is the Larus gulls circumpolar species "ring". The range of these gulls forms a ring around the North Pole. The Herring Gull, which lives primarily in Great Britain, can hybridize with the American Herring Gull (living in North America), which can also interbreed with the Vega or East Siberian Herring Gull, the western subspecies of which, Birula's Gull, can hybridize with Heuglin's gull, which in turn can interbreed with the Siberian Lesser Black-backed Gull (all four of these live across the north of Siberia). The last is the eastern representative of the Lesser Black-backed Gulls back in north-western Europe, including Great Britain. However, the Lesser Black-backed Gulls and Herring Gull are sufficiently different that they cannot interbreed; thus the group of gulls forms a continuum except in Europe where the two lineages meet. A recent genetic study has shown that this example is far more complicated than presented here (Liebers et al, 2004).

 
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