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Tuesday, November 18, 2014

Whale evolution


Evidence for the evolutionary development of whales will be tougher for the creationist to handle. He will probably say that God may have used a similar design plan for aquatic mammals as for terrestrial mammals, and that their similarity therefore does not show evolutionary connection. We might think, however, that these similarities are more plausibly explained as due to evolutionary development of one from the other. Even then, that would at most show that the primal “kinds” were broader than at first envisioned by the Young Earther.  
Read more: http://www.reasonablefaith.org/evolution-without-god#ixzz3JU0nO9s5

I'm not a marine biologist, much less a cetacean biologist, but I'll venture a few comments:

i) Craig's comparison is misleading inasmuch as whale evolution isn't simply an alternative to young-earth creationism, but old-earth creationism as well. 

ii) Darwinians typically allege that the only reason Christians would deny whale evolution is owing to their precommitment to Scripture.  Even if that were true, I don't think that's a damning indictment. 

That said, let's bracket Scripture for a moment. The evolution of marine mammals would be more plausible if marine mammals were poorly adapted to their aquatic environment compared to fish.

Indeed, if evolution is true, shouldn't we expect marine mammals to be poorly adapted compared to fish? If you begin with the bodyplan of a land mammal, you're starting with something that's fundamentally ill-suited to a completely different medium. Like trying to convert a Ferrari to a submarine. 

By contrast, if evolution is true, fish evolved in a marine environment from scratch. Or at least from microbes with precious little specialization. So they were very malleable at that stage.

Since that's their element from the outset, they ought to be perfectly adapted to their environment. Or at least as well-adapted as any trial-and-error process can be.

Yet, to my knowledge, marine mammals are exceptionally well-adapted to their environment. Marine animals are fully competitive with fish. Just as efficient as fish. To use theological terminology, they are wonderfully designed or engineered for their environment. 

In fact, if we were just judging them on their own terms, if there were no land mammals to compare them to, how would we arrive at the conclusion that they were ever anything other than marine creatures? 

iii) Apropos (ii), how could intermediate marine mammalian species become competitive with fish? If evolution is true, fish had a huge head start. Presumably, fish were well-developed, well-adapted to aquatic existence at a time when some mammals were first attempting to make the very awkward, very time-consuming transition from one medium to another. 

How could mammals which were initially ill-adapted to an aquatic existence have the opportunity to become well-adapted when they had to compete with fish–which were already fully acclimated to that medium? Fish were always in their element. 

iv) Finally, why would God create marine mammals as well as land mammals? One reason is to demonstrate his versatility and ingenuity. 

6 comments:

  1. Another aspect of phenotype similarities that tends to be overlooked are the more fundamental levels, such as protein folding. There are only a relatively few finite number of ways to get any protein to fold in a manner that will be useful for the continuance of life. In that regard, it's a simple math problem (simple meaning in conception, not in calculation).

    Suppose that there are X number of ways to do task A, and you attempt to do it Y times. If X is far greater than Y, then you might expect there to be no duplicates. On the other hand, if X is far smaller than Y, then duplicates are necessary. Some practical examples of this could be such things as houses. In order for a house to be livable, it has to at least have some way of protecting the occupants from the elements. There are only a few ways to accomplish this, falling into such patterns as having walls and a roof. Therefore, no matter how ornate an architect might be, the basic pattern of a house will have walls and a roof. Exceptions to these rules require either a specific environment where the occupant will not be discomforted (such as living on an exotic beach with no hurricanes), or else a building that is more artistic than practical (in which case, it's not so much a house as it is an art project).

    In the same way, if there are only a certain number of ways that proteins can fold, there are only a certain number of higher-order "blocks" that can be formed from those proteins, and those higher-order "blocks" can only become a certain number of structures used by organisms. If you have a large number of organisms attempting to do the same basic tasks in life, the limitations of protein folding is going to necessitate a vast amount of overlapping higher-order structures. This is to be expected whether Darwinism is true or false or whether Creationism is true or false, and therefore it constitutes no proof one way or the other in the debate.

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  2. Very well reasoned. Thanks for the contribution.

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  3. Peter,

    I enjoy reading analyses like that but it raises other questions for me:

    You say:

    "There are only a relatively few finite number of ways to get any protein to fold in a manner that will be useful for the continuance of life"

    - and -

    "if there are only a certain number of ways that proteins can fold, there are only a certain number of higher-order "blocks" that can be formed from those proteins, and those higher-order "blocks" can only become a certain number of structures used by organisms"

    What would explain these limitations in the first place? Isn't it God who originally gives chemicals their properties? Isn't it God who decides that a certain configuration of atoms behaves one way rather than another? If that is so, I am interested to know why there would be a restriction (particularly an extreme restriction) in ways to get proteins to fold.

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  4. Hello AMC,
    You asked:
    ---
    What would explain these limitations in the first place? Isn't it God who originally gives chemicals their properties?
    ---

    Yes, they are limitations on how God set up the parameters of creation. I think those limitations are in place for the same reason that a novelist might limit the point of view to a certain set of characters, or even to write in the first person. Creation is something that was completely voluntary of God (and I really think the writing motif fits for that reason, and many others). God could have done any number of things, but He decided to do certain things instead.

    Now, can people question why God did such things? Yes, obviously they can do so. And I think probing those questions helps us to see just how delicate of a balance God has achieved in what He's done. God wants to show His creation that He is consistent and steadfast, and therefore creates with a set of rules. He also demonstrates that He is above the restrictions of those rules by performing occasional miracles when He wishes. If we think of each of God's actions as Him revealing some aspect of Himself, of His nature, of who He is when He creates, then I think it makes sense (your results may vary).

    In any case, the ultimate response to why He decided to create using protein folds as restrictions is up to Him. Perhaps He was like a writer who might pen a short story without using the letter "e" just to show that He could do it. There are many hypothetical responses we can give to that, but the Scripture doesn't really delve into it past the broad "God is in charge" view.

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  5. I would also add that there are necessarily logical tradeoffs when you decide to do certain things and put them in action. For instance, if I'm playing a chess game and I decide to move pawn the e4, I cannot simultaneously decide to move pawn to a4. And we can go meta--if I decide that chess is a game that only allows one move per turn I cannot simultaneously and consistently say it allows two moves per turn, etc.

    So in that sense, certain pathways become necessary once the beginning of the path is chosen. This isn't to say that creation itself becomes necessary in its exact features, but rather that when God decided that He wanted to create a particular kind of Earth, then that particular kind of Earth logically entailed the impossibility of anything contradictory to that particular kind of Earth. Thus, the rules for folding proteins may be a second order--or even five billionth order--decision that, were God to change it, would trickle up and make it impossible for Him to have the overall universe He wished to create.

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  6. Just to reinforce what Peter already pointed out about proteins and protein folding:

    I sometimes like the think of proteins as tools. Like a hammer or saw or whatever. There are tons of different proteins, just like there are tons of different tools. But one protein can't necessarily do the job of another protein, just like if we need to hammer a nail into a 4x4, we can't use a saw. But we could use a saw to cut the 4x4 in half. Maybe in a pinch some proteins could do the job of another protein, like using a boot with a metal tip to hammer in a nail. But of course that'd be far from ideal, and there could be adverse consequences down the line.

    However, proteins have to be built well in order to function properly. It'd be like if a hammer is missing its head, then it'd just be a big stick or something. Or if the head of the hammer was made of glass, then it'd immediately shatter on contact with a nail or surface. Or if the head of the hammer was attached upside-down, then it'd be pretty hard to use as a hammer.

    So proteins have to be organized in a certain way in order to work properly in the job they are supposed to do. Just like the parts of a hammer have to be arranged in a certain way for the hammer to work as a hammer, so too proteins have to be arranged in a certain way for a particular protein to work as that particular protein. Protein folding is part of what constitutes this correct arrangement.

    Yet this protein folding (among many other things) is likewise what limits the protein in what it's able to do or not do as a protein. For example, if a protein is folded in such a way so it operates as a hammer, then it can't also simultaneously be folded to operate as a screwdriver. I'm totally simplifying, but hopefully the point goes through.

    What's perhaps interesting is there is a sense in which proteins can build themselves. Proteins building other proteins, ultimately based on the original DNA blueprint. If we imagine the dream tool box: it would contain both an all-purpose instruction manual (DNA) which can build almost anything and everything in a given environment as well as all sorts of tools (proteins) including tools which can build other tools. Likewise proteins can build almost anything and everything that makes up the human body.

    If this analogy is more or less on target, then in this respect God has also embedded in the system a certain amount of flexibility. I mean, of course, the medium is still physically limited, and God can only operate via this physically limited medium of proteins and their structures and folding and so on. But at the same time, there's a sense in which the medium could change itself or adapt itself, at least to a certain degree. Then again, this flexibility or adaptability or whatever we wish to term it is itself part of the medium, and as such it's part of the divinely predetermined limitations inherent in the system.

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