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Discovery: Cancer with teeth coated with "enamel" similar to the enamel in human teeth

Convergent evolution: Researchers have found an enamel-like layer in the tooth of a freshwater crab. The new structure has a surprising similarity to the enamel layer in the teeth of vertebrates, including humans

The crab protects its teeth from wear by creating a hard protective layer like the vertebrates, convergent evolution. Photo: Ben-Gurion University
The crab protects its teeth from wear by creating a hard protective layer like the vertebrates, convergent evolution. Photo: Ben-Gurion University

A joint research team with Ben-Gurion University of the Negev and the Max Planck Institute for Colloids and Surfaces in Potsdam, Germany, found an enamel-like layer in the tooth of a freshwater crab. The new structure has a surprising similarity to the enamel layer in the teeth of vertebrates, including humans.

Tooth enamel is the hardest tissue in the human body. The hard tissues in humans and vertebrates in general, bones and teeth, get their strength and hardness as a result of using minerals made of calcium-phosphate (calcium phosphate). On the other hand, crustaceans, like most invertebrates, use minerals with a different composition made of calcium carbonate (calcium carbonate, chalk). The researchers from Ben-Gurion University, Prof. Amir Berman from the Department of Biotechnological Engineering and Prof. Amir Sagi from the Department of Life Sciences and the National Institute of Biotechnology in the Negev, in collaboration with Barbara Eichmeier and her partners from the Max Planck Institute in Potsdam, studied the jaws of the Australian freshwater crab, Cherax quadricarinthus quadricarinatus).

Dr. Shmuel Bentov from the Ben-Gurion University research group discovered that this crab, unlike other crabs, protects its teeth from wear by creating a hard protective layer made of calcium phosphate, which is surprisingly similar in its microscopic organization to the enamel layer in vertebrates.

"Enamel is the best solution for covering chewing organs. We assume that during the evolution of vertebrates and this cancer, a similar solution to similar needs has evolved independently in both groups. Unlike vertebrates, crabs are able to replace an old tooth with a new one many times during their lifetime, quickly and regularly during their growth," says Dr. Bentov.

It should be noted that the crab's jaws are part of the exoskeleton that the crab sheds from time to time in order to allow its growth. To harden its exoskeleton, the crab uses a mineral made of calcium carbonate (chalk). In crayfish, the deposited mineral is non-crystalline (amorphous) chalk. This phenomenon has a great significance for the life course of cancer. The amorphous mineral is more soluble and allows it to be absorbed from the cuticle in the previous step to remove it, store it, and use it to build the new exoskeleton. However, at the same time as its high solubility, the hardness of the amorphous mineral is also lower, and therefore its suitability for building teeth is poor. Hence the need to produce a hard layer on the surface of the tooth. The solution that developed in cancer and was discovered at Ben-Gurion University is the coating of the tooth with a layer of elongated calcium phosphate crystals, which are arranged in a direction perpendicular to the surface of the tooth and create an organized and dense structure that is remarkably similar to the structure of enamel, the existence of which was unknown in invertebrates.

As a result, the mechanical properties of the outer layer in the cancer tooth are also surprisingly similar to those of enamel. The crystalline structure, the uniform orientation, and the dense packing of the crystals give these layers the high hardness and strength required for function. Therefore, the enamel layer is considered a "masterpiece" of biological mineralization.

It is worth emphasizing that the "enamel" in the crab tooth serves as a hard protective layer on the soft tooth structure underneath which is made like the rest of the exoskeleton, non-crystalline chalk. The team at Ben-Gurion University is currently investigating the creation mechanism of this material and its meanings.


Link to the original article

Enamel-like apatite crown covering amorphous mineral in a crayfish mandible, Shmuel Bentov, Paul Zaslansky, Ali Al-Sawalmih, Admir Masic, Peter Fratzl, Amir Sagi, Amir Berman, Barbara Aichmayer, Nature Communications, DOI: 10.1038/ncomms1839

32 תגובות

  1. "After all, every time something new is discovered, we have to keep something
    First, on the perfection of the Torah, as with the religious person"

    serious
    What is this obsession with evolution? Every scientific theory is a consensus explanation of a collection of facts.. There is no way to understand anything if you don't stick to a consistent explanation.
    To this day, the scientific method succeeds in the test of time, on the other hand 'intelligence' is a substance to fill holes which mainly creates stagnation and stagnation..
    You have a consistent positive explanation, okay.. You don't: live your life and believe what you want only without disinformation, pseudo-scientific nonsense, etc..

  2. Eran,
    A little late, but for your response:
    http://en.wikipedia.org/wiki/Horizontal_gene_transfer, http://scholar.google.co.uk/scholar_url?hl=en&q=http://www.ias.ac.in/jgenet/Vol75No2/219.pdf&sa=X&scisig=AAGBfm1p6gxUCeaYQZ03kcOTR3JDK3iE9A&oi=scholarr&ei=07HAT_TlGa2k0AXe89SkCg&ved=0CBEQgAMoAjAA, and there are many others, just Google it.
    The sentence you cut from the promo for Dr. Debbie Lindel's lecture is out of context and especially since the words were not said precisely but were intended to attract the eye: the intention is that the activity of the viruses causes parts of the genome of some of the affected bacteria to change, and those whose change (rare) is beneficial to their survival and especially in the encounter with said viruses, survive and continue to exist. There is no engineering here - setting a goal, planning in advance, intention, and planned execution of changes - all the things that mean engineering.
    There is no connection between the article in the link you provided and the archaea's exceptions to the "rule" you are trying to imply. The word archaea appears in the article but is unrelated.
    As already written by Zvi, there is no possibility to rule out a hypothesis that has no legs, evidence or logic or even refer to it. The "recipe" you are trying to hypothesize the imaginary existence of is not related at all to horizontal-horizontal transfer and transfer in the direction perpendicular to the horizontal, vertical, is simply normal inheritance, so the reticular effect is explained without any need for a "recipe".
    A method is a way to organize ideas and pass them between people, it is not an enemy of freedom of thought. The use of imaginary concepts without a common basis with the interlocutor is the enemy of freedom of thought because it imprisons it in the first stage of the dialogue, the stage where a common basis is created for such a dialogue.

  3. Yigal
    Send a link to the article on the proofs and evidence for horizontal transfer

    The viruses are definitely genetic engineers,
    "These mutations include changes in gene sequences and even loss of genes from the genome. In this way, viruses affect the gene content and the genetic variation in the genome of their hosts"
    http://www.technion-alumni.org/.upload/natalie/Debbie%20Lindell.pdf

    Ericha is not a phenomenon that goes beyond the properties of nature, but a theory
    "An evolutionary network where there are horizontal connections between the different branches. Another pictorial image used by the two is a potato. The "potato" is the common body with a large volume where lateral gene transfer can take place, and from which multiple and different sprouts emerge - evolutionary branches with a more classical structure."
    https://www.hayadan.org.il/can-you-please-pass-me-this-gene-0607103/

    What I wrote as a hypothesis only, "In my opinion, the totality of the relationships between all the inhabitants of the organism should be understood in regards to traits and genes," I am not opposed to lateral transfer because it does not create anything new, and it is not contradictory
    My guess about "an existing recipe". Maybe even strengthens her. In my opinion, it is more correct to call it "retinal effect"
    This means that the effects can come from any direction from any situation from any creature.

  4. Ernest,
    The horizontal transfer of genes has evidence and evidence, it is not a theory. On the other hand, the imaginary recipe you propose has no evidence, perhaps because such directions have not been tested, although the logic behind such a mechanism is far from what is known in biology.
    There are types of life that have gone beyond what exists according to your definition, for example super-kingdom archaea (http://he.wikipedia.org/wiki/%D7%97%D7%99%D7%99%D7%93%D7%A7%D7%99%D7%9D_%D7%A7%D7%93%D7%95%D7%9E%D7%99%D7%9D), a fact that contradicts your claim that there is a fixed (internal) recipe.
    No one has determined that it is possible to discover all the reasons for the changes that occur in the genome, but only that the principle, which says that changes in genes lead to changes in living things, is consistent.
    The viruses are not "engineers" they use mechanisms that exist inside living cells.

  5. Zvi Z.

    On the subject of the snail, you generally bring a theory that has not a single wife behind it, more than the theory I bring, a theory of horizontal transfer, versus a theory of an existing plan/recipe.

    There is a reality in nature, billions of creatures live together, are created, become extinct, eat, breathe, touch, connect with each other, inside each other, part of each other. In short, a tremendous interrelationship of a dynamic system changes endlessly. With endless influences forms and situations.
    The theory of evolution is right in my opinion that if a component in that vast system, does not fit, does not get along, it is extinct/destroyed, it also could not be defined otherwise.
    But to think that it is possible to discover all the reasons for the changes that apply in the garden, is naive. I will just point out that the viruses are known as genetic engineers by virtue of their ability to influence the activity of the gene, if you add to that the instability of substances including proteins and other types of substances related to the genome. And of course more reasons that we haven't discovered yet. I hope you agree how ridiculous it is to think that you know why and how.

    Since the phenomena in nature with all those billion creatures, which are known at this point, did not deviate from the existing, but only changed, I claim that there is some fixed recipe, otherwise. A variety of very strange phenomena and forms would arise, but this is not the case.

  6. Ernest,

    You wrote that convergent evolution does not convince you enough (why?) but in the case of the snail it is horizontal transfer. Doesn't that convince you either?

    I didn't understand what you mean by the "recipe of ingredients or properties". All possible proteins that can be produced?

    In any case, I cannot refute any claim about the existence of an unknown mechanism that contains information. But I also see no reason to believe him.

  7. Zvi Z

    A. It is strange that after all the many times in the history of science, that teachings and knowledge have flourished and risen and fallen and been changed
    And solid conclusions, you continue to refer to what is currently known as the end of a verse as Urim and Tomm, too bad.

    B. The recipe means that there is a database where there are formulas for the production of various materials, probably using an array. . The genes - a factory to create substances in the organism..

    . I am familiar with the subject of horizontal transfer, after all, every time something new is discovered, we must keep something
    First, about the perfection of the Torah, as with the religious person, in any case, if you think that the idea I brought is not true, simply bring examples, findings or studies, which negate it,

  8. Ernest,

    I don't think that the photosynthetic snail is explained by convergent evolution. The snail does not synthesize the chloroplast by itself, and the genes that support photosynthesis are explained by the horizontal transfer of genes.

    Regarding the horizontal transfer, see: http://www.pnas.org/content/105/46/17867.abstract

  9. A. Since molecules lose their ability to retain their properties when they are "broken" into molecular parts, the smallest units that can retain properties are molecules, in this case nucleotides.
    B. It's hard to understand what you mean by "existing recipe".
    third. You call the phenomena you know not strange - in fact, maybe they are strange? Phenomena that can definitely be called strange are often discovered - such as cancer with enamel teeth - and yet all of them (so far) agree with the theory of evolution.

  10. Yigal

    I certainly appreciate both your knowledge and ability to analyze and explain
    Just try to focus on the points of contention only, we have no debate about the rest of the details.
    A. I claim that the term "smallest in nature" should not be used because it is only an estimate.
    B. You claim adaptation, I claim an existing recipe, the photosynthetic snail, the "bat" people are just that. An expression of the same recipe.
    third. We were supposed to see strange phenomena, after all, the process of extinction also occurs during adult life
    . And not just in the first moments it was created.

  11. Ernest,
    The building blocks of DNA (the nucleotides) are small enough and their quantity in the genetic units is large enough for them to be "the smallest mechanism in nature (without quotation marks!!)" that contains genetic information, that is, one that passes from generation to generation. In this mechanism yes (!) new recipes are created that can also explain your examples. I will not go into the details of specific examples with you, the principle is important - can the mechanism of evolution lead to the diversity of flora and fauna that we see on Earth? In my opinion (and in the opinion of the vast majority of scientists dealing with the subject) the answer is yes. This explanation may not convince you, however, it is possible that you need additional knowledge or study to be convinced - go out and learn!
    By the way, the example of people (I know of one such) who are able to navigate their way using sounds, does not belong to the other examples you gave, they do not constitute a separate species of animals, but phenomena of brain adaptation to limiting conditions.
    The nucleotides in the hereditary structure are exactly the same memory units that you claim are unknown to science: the genetic changes, the mutations that managed to survive both preserve in the genetic "memory" the events that led to their success and are exactly the traits, information and "instructions" for the creation of those organisms that survive and pass on those genes, these memory units, for future generations.
    And finally: in the last paragraph you refer to only one mechanism that participates in the evolutionary process - the random creation of mutations. Without the second mechanism - natural selection - we would really see an infinite number of different forms. But these forms must be viable, we would have the ability to live and the ability to survive, and that's where the process converges through natural selection to those creatures we know. Beyond that, during the billions of years that life has existed on Earth, there is no doubt that various and strange creatures have appeared (and disappeared).

  12. Yigal

    It's simple, I read the "strange" phenomena that are explained by convergent evolution, if I'm not mistaken,
    An explanation that is certainly interesting and convincing, but it is also permissible to think otherwise, I do not believe in some hidden and spiritual soul,
    I'm just presenting a hypothesis, I'd be happy to meet with the facts that disprove or specialize in it, it doesn't matter at all.

    You have already presented the particles or phenomena that we know, but what we don't know is the mechanism
    The smallest "in nature" capable of containing information. So it is possible, (I repeat my words a bit) that random things are indeed called, in the kingdom of genes, but new recipes of materials are not created, only the existing ones are activated.

    For example, it could be that a certain virus knows how to trigger a certain recipe to create a substance using the gene,
    I gave several examples that you can refer to for the claim that the recipe for the ingredients or properties has always existed, for example:
    A marine snail that knows how to carry out photosynthesis like in the plant world.
    People who see/hear through sound waves like in the bat world.
    The sochi, a bird that knows how to choose colors to design and paint literally paint the walls of the nest like humans.
    A crab that grows human-like teeth.
    To me, the existing explanation through convergent evolution, regarding such situations, is not convincing enough.

    Note that all animals are born with prior information, they know how to build a nest, find food, water, court
    raise babies and more. You can find hundreds of behaviors in the animal and plant world that indicate the existence of a past memory
    The genetic traits, which are known as far as I know, the memory traits or the information or the instructions passed between the generations are unknown to science, at this stage. I claim that the recipes for creating substances in the organism also exist in the memory.

    If the concept in the theory of evolution is correct that the change in traits results from disruption or a completely random change in the gene, we should see endless forms, of animals and plants, extremely different. But this is not so, even if there is a random change, it does not break the boundaries of the existing.

  13. Ernest,
    What do you mean by much smaller than a molecule? Atom? electron? Hadron?
    And maybe the awl is out of the bag and you're looking for the "spirit inside the machine"?
    What do you mean by "that the factor is much smaller than a molecule, and is found in every organism without any change, it already contains the recipes for the creation of all the substances that exist in that world. So that any property or substance can appear for no apparent reason in any organism.”?

  14. Yigal

    Here we differ in our opinions, I claim that the factor is much smaller than a molecule, and is found in every organism without any change, it already contains the recipes for the creation of all the substances that exist in that world. So that any property or material can appear for no apparent reason, look at any organism.

    Regarding the "inhabitants of the organism", it is not clear who is actually responsible or in control of that organism, among all the hundreds and even thousands of types of creatures, some of which are recognized as having the ability to influence the genes and their function in other creatures - genetic engineering

  15. Ernest,
    First the factor you are referring to is perhaps the replicating molecules whose most important feature is the ability to replicate. From the moment one such molecule appeared, it took advantage of the environment to replicate itself over and over. From here it is just history: the theory of evolution (and since it is scientific it is only a theory - it can be disproved and in time there will be a better one than it, and this is in contrast to the religious teachings which are frozen, do not change and preserve themselves according to the conditions that were correct hundreds and thousands of years ago), well, the theory of evolution , with natural selection as a sorting tool and with the replication that has errors, gives a reasonable and good explanation for the changes that have taken place during the 3.5 billion years that have passed since the appearance of organisms (the known ones! There may have been replications even before that!). The ability to reproduce, the essence of the existence of these molecules, is the one that brought us this far: every advantage, even the smallest, was translated into replication and this served as a platform for variations that brought the next advantage in environmental conditions.
    Secondly, since there are many trillions of "inhabitants of the organism" as you say, and since the set of relationships mentioned differs from individual to individual, I don't think it is possible to understand the set of relationships - perhaps a part of it, such as with probiotic bacteria or with the flora of the intestines, and that too only in general And not individual.

  16. my father

    I myself treat evolution as a fact, for example I claim that the need for faith arises from the life of the herd in the course
    The millions of years.- The faith reflex.

    First of all, I was only impressed, and this is allowed, that there is a factor originating from the first creature that continues to exist, in all creatures without change, and passes from generation to generation. A reason I don't know what it is, brings one of the possibilities that lies in the same factor to activate a trait or change it through the genome. And so during evolution, traits of plants will be applied in the animal world, of bats in humans, of humans in birds, and so on.

    Secondly, in my opinion, one must understand the entirety of the relationship between all the inhabitants of the organism in regards to traits and genes,
    It seems that each of the inhabitants or some of them has a significant part in the changes that organism goes through, if it is a body at all (according to science, for every "human" cell there are 10 bacterial cells in our body, and there are about 1,400 types of them).

    Maybe try to refer to both sections.

  17. Seriously, that's what the religious preachers made people like you think.
    It is enough for one experiment that predicts something according to evolution (for example bacterial resistance to antibiotics) to show a different result than what was predicted in advance to cancel evolution. The argument that it is within the context of evolution does not hold. If you find in archeology the remains of a rabbit from the time when there were only single-celled animals (the Precambrian period) and you have already succeeded in disproving evolution. This is not a religious dogma and not a default. This is a proven theory just like the theory of gravity.

  18. my father
    You are absolutely right, just a small correction is difficult in experiments to imitate what nature did in those millions of years
    In hundreds of climate types in thousands of different situations.

    It is clear to me that those who are not suitable to live in a certain environment, climate or physical condition without air conditioning, shelters and the health system are extinct. You can't actually define it differently, it's black or white. And it is clear that it is the features of that raogenism that determine its ability to survive or not. Again, this is also clear here, it cannot be defined otherwise.

    What is less clear to me, of course based on reading and listening to lectures, is: what information, memory, plan,
    accompany the whole organism in the same way since the existence of the first, if indeed it started from a single one.
    And what is the "division of roles" within the organism in relation to the changes that apply to it, for each of the partners,
    Viruses, bacteria and species of unicellular and multicellular organisms, each of which has genes, which also pass
    Changes, and any change that one of the partners undergoes, may affect another type of partner and the functioning of the entire organism.

    One of the reasons that the theory of evolution stands "in its entirety" for decades, even though it has opponents, is the difficulty of disproving it in a laboratory experiment, as they have disproved important and famous theories and concepts, in the field of jurisprudence, chemistry and more.

    .

  19. Let's say that 153 years (and maybe another 20 years of Darwin's experiments) in which billions of experiments were conducted, each of which could have disproved evolution and did not, is a sign that it somehow manages to stand the test.

  20. דניאל

    Undoubtedly, the theory of evolution has quite deep roots in consciousness, and it is also possible to explain phenomena in nature through it.
    But I would not be in a hurry and so absolute, to make it as perfect as possible. We have already learned in the past how dozens of old and new concepts and teachings that seemed perfect, disappeared and others arose in their place.

    A situation similar to religious belief is created, every phenomenon that is discovered in nature is immediately explained within the framework
    Evolution, it may indeed be true, and thus many, many questions, thoughts and ideas are locked away.
    The audacity to deny it is immediately associated with the uncomprehending and the creationists.

    Maybe one day we will learn from the mistakes of the past and listen to those deceiving opponents - the talkers of nonsense.

  21. Yigal c.

    It seems that what you said is true, I am referring to a different, lower, more basic factor than the gene
    And the same factor was created for the first time in the first organism, "software" containing a large number of
    functions to create different materials.

    The creation itself is carried out by activating a certain function on the proteins or perhaps on
    Something more basic.

    A number of phenomena in nature made me think this way, here are some of them:
    A marine snail that knows how to carry out photosynthesis.
    The qualities that a male bird named Sochi has.
    Humans with the ability to see/navigate using sound waves.

  22. Ernest,
    It is clear that some genes are found in all organisms - they all have a common origin, and it is clear that some (even extensive) have common genes (for example, all vertebrates). However, it is important to emphasize that there are certain traits (including certain genes) that have evolved separately several times, so even though the traits look the same or similar, they are based on different genes (convergent evolution).

  23. Sometimes gives the impression, only an impression of course without proof or reading material on the matter, that there is a certain genetic factor that is the same and is found in every organism - in everything capable of developing, dividing or growing. That factor contains within it the whole range of possibilities that exist in nature, therefore any phenomenon or even the strangest feature can appear
    In any organism (within fiscal limits) something that does not conflict with the evolutionary concept.

    .

  24. An excellent example of "convergent" evolution is similar to the wings of bats analogous to the wings of birds.

  25. Yair,
    No matter how hard you work and get tired, you will not find (God)! How will you believe? Since you haven't found it, and you won't find it - don't believe it!

  26. Lair:
    Evolution is not random!!!

    At most it can be said that there are random mutations and that's not entirely accurate either.

    No biological technologies. has biological properties.

    Those who seriously study evolution do not try to "convince" but to prove based on facts.

    and most importantly:
    In science unlike in faith: if there is a theory that will correct the existing theory or even contradict it completely then the new theory will be accepted and the previous unsuitable theory will be canceled.
    All that is needed for this purpose is proof!

  27. The theory of evolution as a convincing explanation for the random development of all the biological technologies that exist in life as we know it is intolerable stupidity... (even as an atheist the theory was annoying and unsatisfying) how much can one believe in such stupidity,
    Evolutionists, keep looking for the riddle of life, look for where your failure is! Search
    "You touched and found, believe me,
    You came and did not find, do not believe" (Rashi on the spot - "Do not believe" you are crazy)
    Former atheist

  28. I am amazed by the people who still deny the theory of evolution despite all the evidence that repeatedly since the invention of the theory has continued to prove its correctness by saying that it fits with all the new scientific results and discoveries.

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