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Embryology in the Quran: Difference between revisions
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Another area of mesoderm (lateral plate mesoderm) proliferates especially quickly in certain positions to form the limb buds. There, mesenchyme cells condense into distinct masses within the limb buds. These mesenchyme cells differentiate into chondrocytes, which secrete the cartilage matrix and are embedded in it. Thus cartilage models of the future limb bones gradually form ([[w:Chondrogenesis|chondrification]]). Once the cartilage models have formed and while they are still growing, the cartilage is literally replaced with actual bone by osteoblasts ([[w:Endochondral_ossification|ossification]]) working outwards from centres of the cartilage models. Osteoclasts remove the remnants of the mineralized cartilage. Ossification also starts in the axial skeleton some time after it has begun in the limbs, except for the upper and lower jaw, which start to ossify slightly earlier. | Another area of mesoderm (lateral plate mesoderm) proliferates especially quickly in certain positions to form the limb buds. There, mesenchyme cells condense into distinct masses within the limb buds. These mesenchyme cells differentiate into chondrocytes, which secrete the cartilage matrix and are embedded in it. Thus cartilage models of the future limb bones gradually form ([[w:Chondrogenesis|chondrification]]). Once the cartilage models have formed and while they are still growing, the cartilage is literally replaced with actual bone by osteoblasts ([[w:Endochondral_ossification|ossification]]) working outwards from centres of the cartilage models. Osteoclasts remove the remnants of the mineralized cartilage. Ossification also starts in the axial skeleton some time after it has begun in the limbs, except for the upper and lower jaw, which start to ossify slightly earlier. | ||
Meanwhile, the process of limb muscle formation begins as soon as the limb buds appear. Myoblast cells migrate from somites to populate the limb buds. They aggregate into distinct masses | Meanwhile, the process of limb muscle formation begins as soon as the limb buds appear. Myoblast cells migrate from somites to populate the limb buds. They aggregate into distinct masses as the condensing mesenchyme starts to chondrify, and before the resulting cartilage models begin to ossify. Over time the myoblasts in these masses differentiate into fused myotubes which form muscle fibres. | ||
====The Timing of These Processes==== | ====The Timing of These Processes==== | ||
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The scientific evidence shows that the development of cartilage/bone and muscles is contemporaneous. | The scientific evidence shows that the development of cartilage/bone and muscles is contemporaneous. | ||
A very detailed account of musculo-skeletal development in the human limb by clinical-geneticist Robert Jan Galjaard covers this subject.<ref>Galjaard, R.J.H. [http://repub.eur.nl/res/pub/10474/030924_Galjaard,%20Robert-Jan%20Harmen.pdf Mapping Studies of Congenital Limb Anomalies]. Ablasserdam: Haveka, B.V., 2003, page 16 [http://www.webcitation.org/6lFwBQq9z webcitation archive link]</ref> It details that muscle precursor cells migrate from the somites into the limb buds (ca. day 26) | A very detailed account of musculo-skeletal development in the human limb by clinical-geneticist Robert Jan Galjaard covers this subject.<ref>Galjaard, R.J.H. [http://repub.eur.nl/res/pub/10474/030924_Galjaard,%20Robert-Jan%20Harmen.pdf Mapping Studies of Congenital Limb Anomalies]. Ablasserdam: Haveka, B.V., 2003, page 16 [http://www.webcitation.org/6lFwBQq9z webcitation archive link]</ref> It details that muscle precursor cells migrate from the somites into the limb buds (ca. day 26). This is well before the condensing core of mesenchyme has started to chondrify into cartilage bone models in the upper part of the upper limb (ca. day 37), followed by the lower part (ca. day 41). The myoblasts have grouped into distinct dorsal and ventral masses by that stage (they do so in the upper limb by day 36 and the start of chondrification according to Sivakmur et. al<ref>Sivakumar, B. et. al. ''Congenital Hand Differences'' in Farhadieh, R. et. al. (ed.) Plastic and Reconstructive Surgery: Approaches and Techniques, Chichester: Wiley, 2015, p.660 [https://books.google.co.uk/books?id=tCq9BgAAQBAJ&pg=PA660#v=onepage&q&f=false Google books preview]</ref>). The upper limbs later start to ossify (ca. day 54). Chondrification of mesenchyme, the grouping of myogenic masses, and ossification all occur in a proximal-distal order (upper to lower part of each limb). The digits of the hands only start to chondrify ca. day 51. | ||
Professor Peter Law | Professor Peter Law concurs that myoblasts are found in the limb buds day 26.<ref>Law, Peter et al., ''Pioneering Human Myoblast Genome Therapy as a Platform Technology of Regenerative Medicine.'' In: Stem Cell Therapy. Erik Greer (Editor). Nova Science Publishers, Inc. 2006. Page 3.</ref> | ||
A detailed account by Walker and Miranda, including useful diagrams, confirms that after day 35, the premuscle regions of the limb containing myoblasts and fibroblasts become distinct, and by day 45 the myoblasts have started to fuse together to form the first myotubes (which continues for some weeks, forming the muscle fibres).<ref>Walker, U. A., and Miranda, A. F. ''Muscle Metabolism in the Fetus and Neonate'' in Cowett, R. M. (ed.) Principles of Perinatal-Neonatal Metabolism, 2nd Edition, Volume 1, New York: Springer, 1998, pp.642-643 [https://books.google.co.uk/books?id=eoy-BwAAQBAJ&pg=PA642#v=onepage&q&f=false Google Books preview]</ref> | |||
In the 10th edition (2016) of the Developing Human, Keith Moore says that ossification of the long bones begins in the 8th week, starting with the upper limbs, followed by the lower limbs and pelvis<ref>Keith L. Moore, Ph..D., FIAC, FRSM T.V.N. Persaud, M.D., Ph.D., D.Sc., FRCPath W.B., The Developing Human: Clinically Oriented Embryology, 10th Edition, Philadelphia: Elseiver, 2016, p. p.349 [https://books.google.co.uk/books?id=pmKGBwAAQBAJ&pg=PA349#v=onepage&q&f=false Google Books preview]</ref> (which concurs with Galjaard cited above). | |||
According to Rugh, Building blocks are present for 40 pairs of muscles, which are located from the base of the skull to the bottom of the spinal column by day 28<ref>Conception to Birth Roberts Rugh, Ph.D., Landrum B. Shettles, Ph.D., M.D. Harper & Row, (New York), 1971, p.35</ref> (these are the myotomes of the somites). Muscles appear in the pelvis day 31<ref>ibid. p.43</ref>. Movement of the muscles is being controlled by the nervous system by the 6th week <ref>ibid. p.34</ref>. All of the muscle blocks have appeared by day 36 after conception<ref>ibid. p.46</ref>. | With axial musculo-skeletal development, Walker and Miranda explain that myotomes have migrated (these form axial muscle) and sclerotomes have started to condense into mesenchyme (which will form cartilage) in the 5th week.<ref>Ibid.</ref> According to Rugh, Building blocks are present for 40 pairs of muscles, which are located from the base of the skull to the bottom of the spinal column by day 28<ref>Conception to Birth Roberts Rugh, Ph.D., Landrum B. Shettles, Ph.D., M.D. Harper & Row, (New York), 1971, p.35</ref> (these are the myotomes of the somites). Muscles appear in the pelvis day 31<ref>ibid. p.43</ref>. Movement of the muscles is being controlled by the nervous system by the 6th week <ref>ibid. p.34</ref>. All of the muscle blocks have appeared by day 36 after conception<ref>ibid. p.46</ref>. | ||
It is apparent from the above that muscle masses have started to form around the mesenchyme condensations around the same time as they begin to chondrify into cartilage models of the limb bones, and long before they have even begun to ossify. Similarly, the process of muscle and cartilage formation begins at the same time for the axoskeleton. Muscles and cartilage, and bone that replaces it, continue their formation in parallel with each other. | It is apparent from the above that muscle masses have started to form around the mesenchyme condensations around the same time as they begin to chondrify into cartilage models of the limb bones, and long before they have even begun to ossify. Similarly, the process of muscle and cartilage formation begins at the same time for the axoskeleton. Muscles and cartilage, and bone that replaces it, continue their formation in parallel with each other. | ||
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====Problems With The Quranic Description==== | ====Problems With The Quranic Description==== | ||
Firstly, it is clear that bone formation (ossification) begins long after muscle has begun to develop around its precursors. Therefore, there is no scientific basis for the Quranic claim of a stage in which bone is later covered with flesh after its own formation. The prefix fa before kasawna means "and then", indicating an uninterrupted sequence.<ref>فَ fa - [http://www.studyquran.org/LaneLexicon/Volume6/00000105.pdf Lane's Lexicon] Volume 6, page 2322</ref> | Firstly, it is clear that actual bone formation (ossification) begins long after the process of muscle formation has begun to develop around its precursors. Since the myoblasts have already migrated and aggregated into distinct masses, nor can their subsequent fusing into myotubes and muscle fibres be described as "clothing" the bones (which in any case ossify in parallel). Therefore, there is no scientific basis for the Quranic claim of a stage in which bone is later covered with flesh after its own formation. The prefix fa before kasawna means "and then", indicating an uninterrupted sequence.<ref>فَ fa - [http://www.studyquran.org/LaneLexicon/Volume6/00000105.pdf Lane's Lexicon] Volume 6, page 2322</ref> The whole verse conveys a sequential process. | ||
It is sometimes claimed that the Quran was only referring to precursor cartilage models of the bones and not bone itself. However, this does not explain why the author of the Quran mentioned not cartilage (ghudhroof)<ref name="LLghudtroof">غضروف ghudhroof, alternatively spelt غرضوف ghurdoof - [http://www.studyquran.org/LaneLexicon/Volume6/00000032.pdf Lane's Lexicon] Volume 6, page 2248</ref>) but only bone ('itham)<ref name="LLitham"></ref>, which literally replaces the cartilage and starts to form well after muscle building blocks are in place. | |||
In any case its embryology would still be wrong. We have seen that muscle and bone (or their precursors) develop contemporaneously, although the parallel processes start when | In any case its embryology would still be wrong. We have seen that muscle and bone (or their precursors) develop contemporaneously, although the parallel processes start when myoblasts migrate and form distinct masses around condensations of mesenchyme that have only just begun to differentiate into cartilage, as detailed above. | ||
For the same reason the Quran would still be wrong even | For the same reason the Quran would still be wrong even to suppose, with a further stretch, that it means only the very beginning of the formation of the cartilage (chondrification) before they are in any sense complete shapes. Going back earlier still, it can even be pointed out that the precursors of muscles (myoblasts) and precursors to the cartilage (mesenchyme) are present in the limb bud as soon as it arises. | ||
However, the natural reading of verse 23:14 is that the bones have some sort of meaningful shape, and can meaningfully be called bones. This is certainly not the case when the condensed mesenchyme has merely started to produce cartilage. Furthermore, the natural reading of verse 23:14 is that all the bones have some meaningful presence worthy of the label 'bones' before Allah clothes them with flesh. As noted in the evidence above, fingers only start to even chondrify after muscle formation is already well underway in the upper part of the limbs. | |||
We have more evidence that 23:14 refers to things already recognizable as bones being clothed with muscles or flesh elsewhere in the Quran. Verse 2:259 uses the same Arabic words as does 23:14 for 'bones', 'clothed' and 'flesh' to describe the resurrection of a donkey which had been dead for 100 years.<ref>[...]and look at your ass; and that We may make you a sign to men, and look at the bones, how We set them together, then clothed them with flesh[...] | We have more evidence that 23:14 refers to things already recognizable as bones being clothed with muscles or flesh elsewhere in the Quran. Verse 2:259 uses the same Arabic words as does 23:14 for 'bones', 'clothed' and 'flesh' to describe the resurrection of a donkey which had been dead for 100 years.<ref>[...]and look at your ass; and that We may make you a sign to men, and look at the bones, how We set them together, then clothed them with flesh[...] | ||