The Creationist Explanaton

[Anguspure]

Which is the question posed in the OP. Why are they different?

But the question "why" implies reason and reason implies intellect.

On evolution there need be no reason at all, just an alphabet soup type of accident that happened to have selective advantage in a given environment.

The beginning of answering "why" is to recognise that form follows function for a purpose, which is a top down process, that necessarily involves a designer.

 

[Occams Barber]

No human being, including creationists, knows the answers to all the mysteries in life. Someone who studies dolphins and sharks would better know what makes their tails useful.

I am frankly aghast that we can assemble the cream of our local Creationist intelligentsia (plus Dreadnought) and they are unable to answer a simple question.
OB

 

[Anguspure]

But that's the whole point. There already exists an explanation based on the respective evolutionary origins of the different groups of organisms: purely aquatic for sharks going back to Cambrian origins from primitive chordates and inheritance of side-to-side undulation for underwater movement, versus dolphins originating from terrestrial mammals and differing inherited spinal structures more easily allowing vertical undulation for movement.

This really isn't a mystery at all.

It doesn't supply the answer to the question "why?" either. It only shows me a supposed series of accidents that turned out to have selective advantage.
There is no goal or purpose in any of it, my inquisitive son would not be satisfied with such an answer.

 

[mark kennedy]

Or diversity is part of good design? Somebody mentioned that.

Well...yea...I've seen some bizarre arguments but this one takes the cake.

 

[mark kennedy]

I am frankly aghast that we can assemble the cream of our local Creationist intelligentsia (plus Dreadnought) and they are unable to answer a simple question.
OB

I'm aghast that you would take the question seriously.

 

[pitabread]

But the question "why" implies reason and reason implies intellect.

"Why" in this context simply relates to the underlying explanation for each organism's anatomy. There is no implication of anything beyond that.

If you want you could always rephrase it: What is the explanation for dolphins tails being horizontally-shaped while shark tails are vertically-shaped?

On evolution there need be no reason at all, just an alphabet soup type of accident that happened to have selective advantage in a given environment.

From an evolutionary point-of-view, the reason is the respective evolutionary lineage of each group of organisms. Specifically that sharks have a fully aquatic history going back to early chordates which used side-to-side undulation for movement underwater. Whereas dolphins had substantially different evolutionary path which included terrestrial mammalian origins.

The beginning of answering "why" is to recognise that form follows function for a purpose, which is a top down process, that necessarily involves a designer.

And I'm giving you the benefit of the doubt here to provide such an explanation. I'll admit I got a chuckle out of "less awkward dolphin sex" as a reason, but unfortunately it doesn't answer why sharks weren't given the same privilege.

 

[Occams Barber]

I'm aghast that you would take the question seriously.

'Tis no laughing matter Mr Kennedy. The collective 'stab in the dark' responses are however proving to be a source of some amusement.
OB

 

[pitabread]

It doesn't supply the answer to the question "why?" either. It only shows me a supposed series of accidents that turned out to have selective advantage.
There is no goal or purpose in any of it, my inquisitive son would not be satisfied with such an answer.

If you're looking for a broader metaphysical purpose or meaning behind everything, you're not necessarily going to find that answer in science. Science is about describing the universe and things in it as we see them and determining explanations for them within the scope of that universe.

In the context of biological diversity evolution is that explanation. You might not like that there is no broader purpose beyond reproductive success. But oh well. The purpose of science isn't personal comfort; it's simply to describe things as they are.

 

[dreadnought]

But that's the whole point. There already exists an explanation based on the respective evolutionary origins of the different groups of organisms: purely aquatic for sharks going back to Cambrian origins from primitive chordates and inheritance of side-to-side undulation for underwater movement, versus dolphins originating from terrestrial mammals and differing inherited spinal structures more easily allowing vertical undulation for movement.

This really isn't a mystery at all.

Clearly the sharks' method of propulsion is superior to the dolphins'. Why haven't the dolphins further evolved to develop tail structures like the sharks?

 

[dreadnought]

I am frankly aghast that we can assemble the cream of our local Creationist intelligentsia (plus Dreadnought) and they are unable to answer a simple question.
OB

I never called myself a creationist, since I don't know exactly what a creationist is, but I think I've answered every question posed to me in this thread, so far.

 

[Anguspure]

"Why" in this context simply relates to the underlying explanation for each organism's anatomy. There is no implication of anything beyond that.

Maybe the intellect of some is satisfied by such an interpretation of the question, I can tell you that the children I have asked why are not satisfied by the assertion "There is no implication of anything beyond that." especially when design is so self evident.

"Biologists and engineers who still want to believe that life's elegant complexity results from neo-Darwinian processes may find that the only way to do so is to keep repeating Francis Crick's mantra—"Biologists must constantly keep in mind that what they see was not designed, but rather evolved"—over and over to themselves." Casey Luskin

If you want you could always rephrase it: What is the explanation for dolphins tails being horizontally-shaped while shark tails are vertically-shaped?

You a right, you could twist the intent of the question any way you wish to limit the enquiry. But that would be a disservice to the person asking why.

From an evolutionary point-of-view, the reason is the respective evolutionary lineage of each group of organisms. Specifically that sharks have a fully aquatic history going back to early chordates which used side-to-side undulation for movement underwater. Whereas dolphins had substantially different evolutionary path which included terrestrial mammalian origins.

Still doesn't tell anybody why.

And I'm giving you the benefit of the doubt here to provide such an explanation. I'll admit I got a chuckle out of "less awkward dolphin sex" as a reason, but unfortunately it doesn't answer why sharks weren't given the same privilege.

This sort of puerility about basic sexual function, is not a sign of a well developed intellect.

 

[pitabread]

Clearly the sharks' method of propulsion is superior to the dolphins'.

How do you figure?

Why haven't the dolphins further evolved to develop tail structures like the sharks?

It has to do with the overall anatomy of the respective organisms and differences in how they propel themselves through the water, which in turn is owing to the evolutionary ancestry of each lineage: Undulatory Swimming

 

[Anguspure]

If you're looking for a broader metaphysical purpose or meaning behind everything, you're not necessarily going to find that answer in science. Science is about describing the universe and things in it as we see them and determining explanations for them within the scope of that universe.

How true. Once again however you are trying to second guess the one making the enquiry in an attempt to limit the converstion.
That this was the original purpose of methodological naturalism for scientific enquiry does not mean that everyone is obligated to follow suit, and certainly we do a great disservice to the young by shutting them down in this way.

In the context of biological diversity evolution is that explanation. You might not like that there is no broader purpose beyond reproductive success. But oh well. The purpose of science isn't personal comfort; it's simply to describe things as they are.

The purpose of science is enquiry, perhaps limited to methodological naturalism for the purpose of focus.
But a Scientist that demands that all legitimate enquiry make no reference to reality beyond the natural is a metaphysical claim (that no such possibility exists) and expresses a flawed ideaology.

 

[pitabread]

I can tell you that the children I have asked why are not satisfied by the assertion "There is no implication of anything beyond that." especially when design is so self evident.

Then give me an explanation for the differences between shark and dolphin tails based on design.

Simply repeating that design is "self-evidence" but not being able to proffer any sort of explanations based on it isn't useful.

 

[dreadnought]

How do you figure?



It has to do with the overall anatomy of the respective organisms and differences in how they propel themselves through the water, which in turn is owing to the evolutionary ancestry of each lineage: Undulatory Swimming

I assume, since the shark has always been a marine animal, that it's developed its tail to the fullest degree. Why, then, doesn't the dolphin evolve so that its tail resembles shark's?

 

[pitabread]

Once again however you are trying to second guess the one making the enquiry in an attempt to limit the converstion.

The question was simply: "Why do dolphin tails go side to side and shark tails go up and down? Why are they different?"

We have an evolutionary explanation. We currently don't have a "design" explanation (e.g. assuming the organisms were independently designed and created).

But a Scientist that demands that all legitimate enquiry make no reference to reality beyond the natural is as a metaphysical claim (that no such possibility exists) is expressing flawed ideaology.

The only way to have testable hypotheses (part of the basic scientific methodology) is to have an underlying framework with which to test them: in this case the framework is the universe itself and the assumption that the universe is objective.

Unless you have a way to objectively test things beyond the "natural", then your objection is moot.

 

[pitabread]

Why, then, doesn't the dolphin evolve so that its tail resembles shark's?

The dolphin's tail is shaped in relation to its overall movement. Its movement in turn is owing to its terrestrial origins from land mammals and spinal structures more geared towards mammalian movement (walking, running, etc) with the legs under the body.

You can see similar types of movement in other aquatic and semi-aquatic mammals like seals, otters, etc.

You can also see differences in movement in different terrestrial animals in a similar fashion.

For example, look at the gait of this Komodo Dragon. It has legs splayed out to the side and side-to-side spinal movement when it walks:

Conversely look at this tiger. It's fully upright (legs underneath its body) and there is slight vertical spinal movement as it moves:

 

[dreadnought]

The dolphins tail is shaped in relation to its overall movement. Its movement in turn is owing to its terrestrial origins from land mammals and spinal structures more geared towards mammalian movement (walking, running, etc) with the legs under the body.

You can see similar types of movement in other aquatic and semi-aquatic mammals like seals, otters, etc.

I now what the dolphin's tail stems from, but why hasn't it evolved further?

 

[pitabread]

I now what the dolphin's tail stems from, but why hasn't it evolved further?

"Further" how? I mean, it does what it needs to do which is propel the dolphin through the water. What else is it supposed to do?

 

[dreadnought]

"Further" how? I mean, it does what it needs to do which is propel the dolphin through the water. What else is it supposed to do?

The shark, which has always lived in the water, has developed the perfect tail for propelling itself through the water. The dolphin has the exact opposite tail. When will the dolphin's evolutionary process catch up to the shark's?