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Philip Cunningham: Darwinism vs biological form



How Do Organisms Achieve Their Basic Form? That is to ask, how does a single fertilized egg become a elephant, a tiger, a human, or any of the numerous other kinds of animals or plants we see around us?

“The earliest events leading from the first division of the egg cell to the blastula stage in amphibians, reptiles and mammals are illustrated in figure 5.4. Even to the untrained zoologist it is obvious that neither the blastula itself, nor the sequence of events that lead to its formation, is identical in any of the vertebrate classes shown. The differences become even more striking in the next major phase of in embryo formation – gastrulation. This involves a complex sequence of cell movements whereby the cells of the blastula rearrange themselves, eventually resulting in the transformation of the blastula into the intricate folded form of the early embryo, or gastrula, which consists of three basic germ cell layers: the ectoderm, which gives rise to the skin and the nervous system; the mesoderm, which gives rise to muscle and skeletal tissues; and the endoderm, which gives rise to the lining of the alimentary tract as well as to the liver and pancreas.,,, In some ways the egg cell, blastula, and gastrula stages in the different vertebrate classes are so dissimilar that, where it not for the close resemblance in the basic body plan of all adult vertebrates, it seems unlikely that they would have been classed as belonging to the same phylum. There is no question that, because of the great dissimilarity of the early stages of embryogenesis in the different vertebrate classes, organs and structures considered homologous in adult vertebrates cannot be traced back to homologous cells or regions in the earliest stages of embryogenesis. In other words, homologous structures are arrived at by different routes.” Michael Denton – Evolution: A Theory in Crisis – pg 145-146 More.

See also: Philip Cunningham on determinism vs free will

@kairosfocus Does your "There is a whole cell there in the zygote, which has room for Terabytes’ worth of info..." contradict anything I wrote? Are you saying anything beyond "we don't know"? Maybe you should read the whole thing: http://nonlin.org/dna-not-essence-of-life/ Nonlin.org
@5 ... indeed adequate! ayearningforpublius
From one of the articles quoted in the notes: What Do Organisms Mean? Stephen L. Talbott - Winter 2011
Harvard biologist Richard Lewontin once described how you can excise the developing limb bud from an amphibian embryo, shake the cells loose from each other, allow them to reaggregate into a random lump, and then replace the lump in the embryo. A normal leg develops. Somehow the form of the limb as a whole is the ruling factor, redefining the parts according to the larger pattern. Lewontin went on to remark:
Unlike a machine whose totality is created by the juxtaposition of bits and pieces with different functions and properties, the bits and pieces of a developing organism seem to come into existence as a consequence of their spatial position at critical moments in the embryo’s development. Such an object is less like a machine than it is like a language whose elements ... take unique meaning from their context.[3]
A context of meaning can be thought of in various terms. We can take it, for example, to be the organism’s unified form in the fullest sense — not only its bodily form (as a flexible, dynamic trajectory of development), but also the “shape” of its pattern of activity, its recognizable and irreducibly qualitative way of being, distinct for every species.[4] Every organic form is a gesturing, which is also to say, a kind of speaking or an expression of meaning. And we could just as well say that the organism’s gesturing manifests the character we recognize in the organism as a whole. Gesture, character, significant form, a tapestry of meaning — these terms all point to the “something more” that, as we found earlier, makes the language of physics and chemistry inadequate to describe the organism.
If the language of physics and chemistry is inadequate to describe the organism, which language is adequate to describe the organism? Perhaps the language used to say this, 3000 years ago is more than adequate.
For thou hast possessed my reins: thou hast covered me in my mother's womb. I will praise thee; for I am fearfully and wonderfully made: marvellous are thy works; and that my soul knoweth right well. My substance was not hid from thee, when I was made in secret, and curiously wrought in the lowest parts of the earth. Thine eyes did see my substance, yet being unperfect; and in thy book all my members were written, which in continuance were fashioned, when as yet there was none of them. How precious also are thy thoughts unto me, O God! how great is the sum of them! If I should count them, they are more in number than the sand: when I awake, I am still with thee. -- Psalm 139:13-18
Nonlin.org: By the way, my compliments for the site. It's very interesting! :) gpuccio
Nonlin.org: I absolutely agree. Unfortunately, I do agree also on this statement of yours: "If not in DNA, then where exactly is the actual human blueprint? We do not have any strong leads, but we do know that even genetic twins are somewhat different, that epigenetics play a role, that some information is encoded chemically (as in redox reactions and DNA PCR), and that environment and the maternal womb are critical. None of these is a sufficient explanation however. Chemistry is common to all organisms, the environment can vary drastically without affecting the outcome that much (homeostasis), and the maternal womb is itself an outcome of a previous development." You say it correctly: we do not have any strong leads. Your arguments are very similar to a question that I have been asking for many years here: what we know about genetics (and, I would add, epigenetics, which is actually a lot) tells us much about the effectors, and, with the help of epigenetics, also about specific cascades of effectors. But we still understand nothing about the controlling procedures. So the question is: where and how are the controlling procedures written? In 2003 the italian biologist Giuseppe Sermonti published a book whose English title is: "Why Is a Fly Not a Horse?" His question remains absolutely valid today. I think that some basic new understanding of living beings is necessary to start solving that problem. And, probably, some basic new understanding of biophysics, and even of physics. gpuccio
Non-lin: There is a whole cell there in the zygote, which has room for Terabytes' worth of info embedded in functionally specific organisation. regulatory networks, metabolic processes and more. DNA is patently only part of the story. KF kairosfocus
Fact 1: Making anything from scratch requires raw materials and information. Fact 2: Making the simplest products like pencils and tires requires many times more than 1 GB of data as manufacturers employ thousands of engineers that generate the information necessary in extracting and refining the raw materials, in making the building blocks, in making the tools and the tools that make the manufacturing tools. Fact 3: The human body is the most complex entity known; more complex than pencils, tires, computers, the whole of the internet (arguably). Fact 4: DNA in its linear form contains only 1GB of data. Fact 5: DNA is not particularly well compressed for information – 64 bits (3 nucleotides) encode 20 aminoacids; up to thousands of nucleotides encode a single protein. Assumption 1: DNA 3D structure and other chemical properties of cells add an unknown amount of information which is also not known how it differs from organism to organism. Until further research proves otherwise, assume this increased information offsets compression inefficiencies from Fact 5. Fact 6: Human DNA differs from chimp DNA by 1.2% and from banana DNA by 50% while human DNA differs from other humans by up to 0.5%. Fact 7: Humans differ from chimps in several dimensions including development, anatomy, intelligence, and behavior. Simply describing all these differences take a large volume of data. Conclusion 1: From Fact 1, 2, and 3 – it takes an unknown yet very large amount of data to store the information necessary to develop a human from zygote to birth. Conclusion 2: From Conclusion 1 and Fact 4 – the human DNA is grossly inadequate to store the information needed to develop a human from zygote to birth; DNA is not what makes us human! Conclusion 3: From Conclusion 2 and Facts 6, 7 – humans differ from chimps by orders of magnitude more than the 8 MB of data difference in the two DNAs; DNA fails to support the assertion that humans are apes! More: http://nonlin.org/dna-not-essence-of-life/ Nonlin.org

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