The argument of vestigiality is a hard one to make. Anything can be found to have a function. The little toes, wisdom teeth, the appendix, the whale pelvis, snake arms, etc.
The real argument against the appendix comes with bad design. It is obvious that we don’t need it to live, and it certainly has killed its share of people.
Much better arguments for vestiigality come from pseudogenes. Most mammals can synthesize vitamin C. Primates can’t, because the gene coding for the enzyme necessary for making vitamin C is broken. Obviously we evolved in an environment where lack of dietary vitamin C was not a huge factor. So the remnants of this gene (which are quite easily identified) in primates is vestigial. Serves no function, there is no reason for it to be there and broken in humans, the fact that it is there and broken in other primates but not other mammals implies common descent. You get the picture.
Ed: I am sensing a fellow biologist here. I feel a really strong argument for evolution could be made based on symbiotic (really, symbiogenesis of) internal organelles.
What do you think?
OTOH, if people are going to throw up their hands and plead willful ignorance when confronted with fossil evidence, a long discussion about electron transport and eukaryotic vs. prokaryotic membranes isn’t gunna help.
One using your argument would have to explain why common components are used in some cases, and not in others, and the cases where they are reused correspond to DNA evidence for common descent. If the design of the eye for the squid and the human were the same, then the argument for the reuse of components would be good.
As for the OP, I would ask for evidence of when evolution started, if it is working now but not at some time in the past.
Again, as I’ve pointed out, the whole concept of “junk” DNA is under dispute.
Moreover, while a designer might not specifically “re-use” non-working components, it’s hardly inconceivable that a designer would allow certain flaws to remain and be propagated – especially in a world like this, where disease and genetic infirmities are allowed to exist. The designer wouldn’t be re-using these flaws, but he could certainly permit their continued existence.
And as I’ve pointed out, the existence of DNA isn’t a compelling argument either way. It is consistent with evolution, but it is also consistent with deliberate design. To say that this is “evidence” is a foolish argument, as it does not truly support either side.
As TVAA and I have pointed out, that’s in dispute, which is why I wouldn’t use this as an argument in this situation.
First of all, even spaghetti code needs a designer, so I think it’s foolish to say that it requires no intelligence. Even a flawed wristwatch still exhibits signs of deliberate design.
Second, every competent engineer knows that design decisions are based on trade-offs – balancing one requirement against another. While DNA may result in spaghetti code, it has other redeeming features – self-replication and vast recombinatorial ability, for example. When it comes to biological systems, I daresay that those are far more important features!
Spaghetti code is a nightmare for systems that continually require reverse-engineering and manual maintenance. Those simply are not compelling requirements for biological systems, since organisms do not (and should not!) require continuous software upgrades.
Darwin’s Finch argued that reusability isn’t a requirement for an omnipotent creator – rightfully so, as I stated earlier. By the same token though, this omnipotent being is under no obligation to avoid spaghetti code. After all, it’s not as though the Creator would have to re-examine his work, and figure out what He did a thousand millenia ago!
With all due respect, I think you’re missing the obvious. Competent engineers know that you should use common design components whenever possible. This does not mean that you should always use common components, especially when tacking different design problems. (For example, I like TTL circuits, and I use them whenever possible – but I would never claim that they should be used in all applications!)
Squid eyes and human eyes are different, and for good reason. Squids live in aqueous environments, whereas humans do not. This alone suggests that squids and humans need not employ the same ocular design.
Remember how I said that competent engineering design requires making trade-offs? In a human eye, the light which impacts the retina has to pass through a layer of blood vessels. This partially obscures the light, but it also provides added protection against UV rays. In contrast, a squid requires no such protection, since it lives deep within the ocean.
So why are there some differences between the bodily components of the squid and the human body? Because they are different organisms, occupying different habitats.
I see that you are moving the goal posts, but I am glad that you are conceding that if there is one, it is not a good designer.
There intelligence, but for the creature that avoided being eaten to then procreate.
And repeating my point helps yours how?
The upgrade is evolution, as the medical researches found in the malaria case.
Seeing the medical biologists, having to deal with evolving genes, I say it is our job to do so! Especially since there is no creator re-examining that.
But it does support evolution. Just because it is consistent with creationism, that doesn’t mean that it isn’t evidence for evolution. What do you think this, a game of Boggle [sup]TM[/sup]?!? “You’ve got ‘DNA’ on your list of supporting evidence? Sorry, I’ve got that on my list, too. Guess we both have to cross it out.”
I don’t understand how, in your world, anyone can come up with evidence of anything. I mean, if I have video of someone shooting someone, his fingerprints on the gun, 20 eyewitnesses, and a signed confession, that’s consistent with the theory that he did. But it’s also consistent with the theory that God really has it out for the guy. How can we choose between the two theories?
As for the OP, saying “I agree that evolution has been observed, but what proof do we have that humans are result of it?” seems a bit like seeing a watermelon splattered across the groung and saying “Well, I agree that gravity is capable of accelerating objects to high speeds, but what evidence do we have that the watermelon hit the ground at a high speed because of gravity?” Once we have a perfectly adequate explanation, it seems to me that that should be the default.
Clearly, the reference to “spaghetti code” must be taken in context, which is, eh, “Intelligent Design.”
The whole point of calling DNA “spaghetti code” is to point out how badly mangled it is, nothing a good human designer will do, let alone what supposely a omnipotent being.
If you use it as an argument for ID, you are misconstruing it.
That’s because we know watches are designed. Show a watch to a member of a primitive tribe who has absolutely no knowledge of watches. He will not see any “signs of deliberate design.”
Could you come up with a better analogy next time? This one has been refuted completely.
Unlike humans, the Chistian god is not bound by trade-offs.
Why are these important features if evolution is not to be considered? These features are only important in light of evolution.
But this omnipotent being is perfect! I must assume He has the highest degree of asthetics, rendering spaghetti code totally unacceptable to Him.
You may think that the issue of junk DNA is under dispute. I work every day with noncoding DNA. My thesis project involves determining what pieces are under functional constraint (i.e. which parts are not junk DNA). Not to sound too cocky, but unless you can give me some peer reviewed research, I am the authority on junk DNA here. If I say its junk, its junk unless you can give me the primary research. I’ll take statements from the other biologists on the board, but I am not going to take popular press articles and assume that the guy who wrote it has a working knowledge of nonfunctional DNA that is superior to mine.
This patently makes no sense. You say that the designer is free to keep totally worthless pieces of DNA which are broken copies of working genes in other organisms. The working copies have a function which would be useful for us, for instance in preventing scurvy.
You are in effect making an argument for a trickster God: a god who created us and the world to look like we evolved. That all of the evidence available (except the Bible) points to evolution. That at every level, there is a beautiful and consistent theory that reflects the paths that life took in forming complexity and eventual sentience. But He expects us not to believe it or research it. This is philosophically unsettling to me, and I can’t imagine you will win many converts if you put it like that.
possum stalkerMy experise is in genetics, which means that I am weak on anything that happens outside of the nucleus. I think the endosymbiotic hypothesis certainly is a lovely example of how life finds novel and creative ways to survive. I have two arguments against using it to demonstrate evolution in general, though. The first is that even amongst the rare events which push along natural selection, complete symbiosis and evolution into one life form is something that has not often been repeated. It is not really an exception, but it is not really something that demonstrates selection and descent, which accounts for the vast majority of evolutionary events. Second, the complexity of the interplay between organelles and the rest of the cell is still very poorly understood. We have little idea what the original bacteria incorporated into eukaryotic cells looked like. Nobody can get near to finding culture conditions for mitochondria and the like. Unfortunately, this can be used as ammunition by people like the intelligent design crowd, who can claim that our lack of data in the area makes it “irreducibly complex” and therefore a system which was unlikely to have evolved by itself.
But, again, the whole concept of “standardization” was concocted by humans as an aid in design. It’s a lot easier for us to work with one or a few designs; again, an omnipotent creator is not so constrained.
Ah, but there’s no reason He should, either. Similarity of design is explained quite well via Darwin’s “descent with modification” (and, indeed, is required by such an argument). It is not explained adequately, nor even required, for creationist arguments. A divine designer could have designed any way he chose, without even considering such concepts as efficiency or standardization. So, creationism (or an argument from design) provides no answers at all with respect to the topic of similarity of design: God could have done so, but he certainly didn’t need to do so. So why did He? Without a means to read the Mind of God, we have no way of knowing.
Right, but that the distribution of the flaws strongly corroborates the phylogenetic tree as laid out by other methods, is significant. The ‘similar features require similar DNA’ argument is a shallow one and is a gross misrepresentation of the way that DNA works - because there are numerous examples of remarkably similar features that don’t arise from the same coding and there are numerous examples of the same DNA performing different function in different organisms.
This is called “special pleading”, aka “grasping at straws”. Ultimately, it is always possible to construct an argument that cannot even theoretically be refuted. However, that also means that the argument also has nothing at all to do with science.
You could respond with: “How can you prove that you are talking to somebody else and are not actually a drooling maniac in a rubber room suffering from an immersive delusionary hallucination?”
I wonder what you are doing that TTL is good for. I haven’t used them since my undergraduate labs a long time ago. I used early ECL for my bachelor’s thesis.
Certainly the squid eye is expected to be different from the human eye in some respects, but it is also different in ways not explainable directly by the environment. (Blind spot, for instance.) If you could show the eye of the whale is closer to the eye of the squid than it is to the eye of the human, you might have something.
Does light pass through these blood vessels in whales?
And if every characteristic were explainable in this way, you might have something. But many are better explained from evolutionary history, such as, most obviously, lungs on a whale. (Unless the designer did this in order to allow a whale to swallowJonah.)
If the designer really reused components, we would expect to see minimal differences between components for different environments, which is not what we see. If an organization has a library of hardware or software modules, you take a module from the library, and modify it as necessary for the application. The next person takes the module from the library, not from you, since your modifications may not be useful. This is especially true if both applications are being written at the same time. If there is no library of common components, and all coding is done by modifying things already there, then you get the kind of mess we see in biological systems.
I’m not a biologist but I am a computer scientist, so a note on spaghetti code. First, it is an obsolete term, since we used to see spaghetti code back when people wrote Fortran II and used lots of gotos. Second, spaghetti code arose not from incompetence but from lack of planning or having to deal with unexpected changes to code. An omniscient designer should be able to anticipate everything, and thus write perfect code in some sense. Spaghetti code is exactly what you expect to see if an existing code base gets modified to deal with unexpected requirements.
Say we have a problem to be solved by a programmer and by a genetic algorithm that writes code. Want to guess which one will result in code that looks more like DNA?
Except that the problem is broader than that; fish, turtles, cetaceans, newts, salamanders have a vertebrate-type eye, yet they live in water; snails live on land and the configuration of their eye is more similar to that of a squid. Your argument doesn’t hold water.
I wouldn’t call it an obsolete term. It’s still used widely, and pejoritavely, to mean “inelegant/convoluted” source code, whatever the term’s original use was. In this regard it shares a similar history with the word “bug”, which once referred to actual insects — moths I think — infesting someone’s vacuum-tube computer. You’ll notice too that dropping GOTO from modern programming languages doesn’t seem to have prevented convoluted code from being written, not that we should be surprised.
Otherwise, I agree with everything else Voyager said.
A question just occurred to me: Are there any genetic diseases that are known to result from bits of junk DNA being activated by mistake? If so, isn’t that another nail in the coffin of the idea that DNA was intelligently designed?
I think the endosymbiotic hypothesis certainly is a lovely example of how life finds novel and creative ways to survive. I have two arguments against using it to demonstrate evolution in general, though. The first is that even amongst the rare events which push along natural selection, complete symbiosis and evolution into one life form is something that has not often been repeated. It is not really an exception, but it is not really something that demonstrates selection and descent, which accounts for the vast majority of evolutionary events. Second, the complexity of the interplay between organelles and the rest of the cell is still very poorly understood. We have little idea what the original bacteria incorporated into eukaryotic cells looked like. Nobody can get near to finding culture conditions for mitochondria and the like. Unfortunately, this can be used as ammunition by people like the intelligent design crowd, who can claim that our lack of data in the area makes it “irreducibly complex” and therefore a system which was unlikely to have evolved by itself.