Posted on 04/02/2009 4:46:24 PM PDT by GodGunsGuts
Envying the Tooth of the Sea Urchin
March 31, 2009 — Did you know the lowly sea urchin has a tooth? It’s not just any tooth: it’s “a remarkable grinding tool,” according to a team of international scientists. They even used the word “exquisite”
in the title of their paper in PNAS.1 Humans might benefit from knowing more about this tool. “The improved understanding of these structural features,” they said, “could lead to the design of better mechanical grinding and cutting tools.”
The sea urchin “tooth” is not really a tooth, but a hard rod with a serrated edge used for crushing the animal’s food (see description at Univ. of Wisconsin about the work of Pupa Gilbert, one of the co-authors). The urchin tooth, which grinds down hard limestone, has the hardness of teeth in higher animals. “Even though the tooth is composed almost entirely of calcite, it is used to grind holes into a rocky substrate itself often composed of calcite,” the abstract from the paper reads. It continues—
Here, we use 3 complementary high-resolution tools to probe aspects of the structure of the grinding tip: X-ray photoelectron emission spectromicroscopy (X-PEEM), X-ray microdiffraction, and NanoSIMS. We confirm that the needles and plates are aligned and show here that even the high Mg [magnesium] polycrystalline matrix constituents are aligned with the other 2 structural elements when imaged at 20-nm resolution. Furthermore, we show that the entire tooth is composed of 2 cooriented polycrystalline blocks that differ in their orientations by only a few degrees.The slight misalignment and interdigitation appears to provide a functional advantage, they found. It provides a corrugated edge that fractures along its cleavage planes so as not to fracture the tooth but actually sharpen it as it cuts. “We also note that in this model, the edges of the individual plates would remain anatomically sharp due to cleavage along the {104} planes, and the cleavage would probably not propagate through the whole tooth tip because of the small misalignment between neighboring plates.” In other words, even the apparent misalignment has a function. They said, in conclusion,A unique feature of the grinding tip is that the structural elements from each coaligned block interdigitate. This interdigitation may influence the fracture process by creating a corrugated grinding surface. We also show that the overall Mg content of the tooth structural elements increases toward the grinding tip. This probably contributes to the increasing hardness of the tooth from the periphery to the tip. Clearly the formation of the tooth, and the tooth tip in particular, is amazingly well controlled.
The mature sea urchin tooth possesses incredible structural and compositional complexity. Here, we show the presence of crystalline blocks composed of 3 different coaligned elements: needles, plates, and polycrystalline matrix. We also show that the tip, and presumably the whole tooth, is composed essentially of 2 such coaligned blocks that differ in their orientations by [less than] 6°.The blocks are also interdigitated in the tip. Furthermore, the Mg concentrations increase toward the center of the tooth tip. We propose that all of these features contribute to the grinding capability of the tooth. A deep understanding of the structural
design features of the tooth tip sheds light on the manner in which one crystalline phase, calcite, can be tailored to fulfill grinding and self-sharpening functions that enable the tooth to be used to grind holes into a substrate that is also composed only of calcite. Much can be learned from the sea urchin tooth that can be applied to the development of improved grinding and cutting tools.
USA, published online before print March 30, 2009, doi: 10.1073/pnas.0810300106.
All together, everyone: how much was said about evolution in this paper? ZILCH! Instead, they used the D word design: they wanted to gain a “deep understanding of the structural design features” of this “exquisite” grinding tool to learn how we might tailor our own bottom-up nanofabrication of crystals to fulfill functions useful to us. This paper had intelligent design all over it – in the research, in the understanding, and in the application.Show this to your biology teacher and tell him or her that “Nothing in biology makes sense except in the light of design.”
“Sorry Fichori, I was being sarcastic.” [excerpt]LOL!
“My silly point was that just because we (men) can think of a scenario to explain an observation it is still only an observation. Since Adam all that man has done is to record the intricacies of what God has made. In describing their observations, they have believed themselves to be possessors of knowledge and wisdom beyond the Creator. Yet they remain journalists recording observations which they had no part.” [excerpt]Interesting take.
“The reason I didn’t notice is because other people have said basically the same thing, except they were serious!”
I was serious in HS also! Our biology teacher spent a couple of days explaining how God and evolution were compatible. (In a Catholic HS no less.) His reasoning was pretty much that God simply set the world in motion and then allowed evolution to run its course. (I’m not sure at what point he felt that God needed to get involved. After all, if God could have waited patiently for a fish to form Halle Berry, he could have waited for a spontaneous “big bang” to occur.)
I wasn’t satisfied with his take so, being convinced of macro-evolution at the time I simply devised a method whereby God could get involved while keeping a bit of Genesis intact; not a bunch of Genesis, just a bit. It was the absence of transitionals in the fossil record that caused me to reconsider my earlier training.
Thanks for the rundown of the Hebrew in your previous post. I haven’t studied these things in many years so it’s good to get a refresher.
Alright, prove god exists and then I’ll do your little experiment.
You changed the subject again by the way. Now you are talking about the creation of life from organic reactions which is an entirely different field of study.
But evolution is a testable theory. Take anything that reproduces rapidly and expose it to an event which causes death to them. For example an ant being exposed to pesticides. After generations the ants with an immune system that can fight the pesticides will be naturally selected and the genetic coding of the ants will change. Happens all the time. If you don’t want to trust science and instead want to believe in a young Earth, that is fine. But realize that it is your faith and nothing else which is your reasoning for believing. There is no scientific proof that favors a young earth. There is scientific proof that suggests a creator exists, but nothing that agrees with the Christian bible. I’m Christian myself by the way, I just don’t spend my day turning people off from my religion.
How dare you ask that! Off with your head! :-)
See there! Whatever happened to drawing and quartering, or keelhauling, or even good old-fashioned crucifiction?
Tap the brakes, ciwwaf. There is no “god”. There is a God. The proof for Him does not fit in the petrie dish.
But, I didn’t change the subject. You made the comment that a “membrane” fit the definition of a “simple” transportation device. With that in view, I asked you to give rise to anything which comes close to this “mutation”. We haven’t moved to the environment preferring one over the other, because the mutations must be in place first for the selection to begin. You want to move it along and show selection at work. Not so fast.
If a membrane did arise randomly, the great puzzler is that a bicycle chain or a cucumber did not also “arise” as a possible mutation for the organism to present to the environment for selection. How many mutations arose while the “right” one was waiting to be rolled out? And, what aided the organism with survival until that arose? You speak as though, “Okay, the membrane is here for propulsion. Check.” But, wait a moment. Evolutionists admit that there is no “driver” to cause mutations. They are random events, then the environment prefers one over the other. My concern is twofold before we get to selection: 1. Why are the mutations that you are claiming arise by random events useful to the organism? Given that there are an infinite number of possiblities, why is the useful one even appearing, at all? And, 2. what provides for the incredibly complex support systems that sustain the mutations in the first place? Again, this is assumed as axiomatic. Don’t ask, thank you.
And evolution is not the same thing as common descent. Your ant example is peculiar, because it is almost as if something is directing the fight against the pesticide. Why would random mutationst give rise to this useful survival mechanism?
I don’t hold to a young earth. A very old earth and universe is completely compatible with the text of the Bible. And, you may not be spending all day doing it, but, clearly you are spending sometime turning folks off about your religion. Randomness is the basis upon which your world operates.
Membranes are usually a bi layer of lipid fats with a hydrophobic tail that allows the creation of a channel between the two layers. Lipids are used for storing energy and are naturally hydrophobic because of their molecular structure. Any life that stored the lipids in a shell around itself would better survive, these lipids would slowly be naturally selected to better serve their purpose of protecting the cell and the hydrophobic string would naturally be naturally selected to grow longer.
This is exactly the response I expected. You argue that mutations are “simple”, such as a membrane for transportation. I rebut that if they are so simple to arise as a random mutation, then build one for us. You say, here is how a membrane is constructed and how it works.
The challenge was, if you are so sure these are “simple” and require no complex support systems to stay “alive”, then MAKE ONE for us, don’t tell us how they are made. You are the one that says “science” is about testable hypothesis. Test it and let us know.
I am getting new dentures next week, I wonder if I could get teeth like this?
I was going to go titanium but apparently some guy in a James Bond movie gave it a bad rep.
I have not personally made one but i use them all the time for organic chemistry and if i was given the materials I could. They don’t have to be alive and can be made from organic or inorganic materials. Their molecular structure is what causes them to be semi-permiable and osmotic pressure is what causes movement of fluid.
They believe that there were dinosaurs walking around with people! Just a few thousand years ago!
Are you all trying to reason with them?!
I’m sitting here reading your post and who it is to...
...And totally getting a kick out of it.
LOL!
I just noticed that myself. Is it really that hard to figure out where I’m coming from?...LOL
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