A recent article on the Aeon web site is entitled "Building Embryos." It is written by a molecular biologist (John Wallingford) who is the past president of the Society for Developmental Biology. The story includes misleading suggestions that developmental biologists are making big progress in understanding how the human body develops in a human womb. The subtitle of the article says, "Now there is a revolution underway." We hear that "influential biologists are making huge strides," and we have a claim of "truly explosive advances in human embryology." The boasts are not substantiated by any facts discussed in the article. Far from getting a portrait of developmental biologists starting to understand how a human body develops, we get an article that suggests developmental biologists still have no credible tale to tell of how such a thing occurs.
The first tale Wallingford offers of how his body got here is a silly boast. He states this:
"Fifty-four years ago, I did something extraordinary. I built myself. I was a single, round cell with not the slightest hint of my final form. Yet the shape of my body now – the same body – is dazzlingly complex. I am comprised of trillions of cells. And hundreds of different kinds of cells; I have brain cells, muscle cells, kidney cells."
No, a person does not build himself. For one thing, the development of a human body within a womb requires the mother, so it is not a do-it-yourself affair in which you "build yourself." And since "you" as a functional human being capable of building things does not arise until late in the process of human development, it is not correct to say that you built yourself. Tiny-clump-you (nine months before your birth) didn't know how to make full-baby-you, so you can hardly boast that you made yourself. What Wallingford should have said is that the enormously organized hierarchical structure of the human body arises through some marvel of coordinated construction that biologists still don't understand. But rather than such honest humility, Wallingford has gone all super-boastful by crowing that he built himself.
Wallingford then states this self-contradictory statement which gives a misleading analogy:
"Our construction proceeds with no architects, no contractors, no builders; it is our own cells that build our bodies. Watching an embryo, then, is rather like watching a pile of bricks somehow make themselves into a house, to paraphrase the biologist Jamie Davies in Life Unfolding (2014)."
It seems we have here someone who is not writing very carefully, as he states in the same sentence both that when a body is constructed there are "no builders" and also that the cells are the builders, which is like someone saying, "I never smoke, and when I do smoke it's in the evening." You do not explain the marvel of the origin of a human body by claiming that cells did it. Half of the marvel of the origin of a human body is the marvel of how there arises about two hundred types of cells used by the human body, none of them specified by DNA or its genes, which do not even specify how to make the organelles from which cells are made. Most type of cells are so complex they have been compared to factories or cities in their complexity. Cells don't have any instructions on how to build things bigger than themselves (or even how to make or reproduce a cell), so you don't explain all the levels of organization higher than cells by just saying that cells built such levels.
As for the analogy about a pile of bricks assembling into a house, it is profoundly misleading, for two reasons. The first is that while a brick is an unorganized thing (a mere block of clay), a cell is a fantastically organized component typically capable of the marvel of self-reproduction, which (given the cell's complexity) is a marvel as astonishing as an automobile splitting into two working automobiles. So it is extremely misleading to compare cells to bricks. Secondly, the organization of a human body is a state of vast organization requiring almost infinitely more coordinated organization than the amount of organization needed to make a house from bricks.
The walls of a house can be built with about 10,000 bricks. An adult human requires about 37 trillion cells of about 200 types, most of which must be placed in the right places in the body. Most of these cells are gigantically more organized than a brick wall, with the average cell requiring a special arrangement of about 100 trillion atoms. Given such a reality, the progression from a speck-sized zygote to the full organization of the human body is not like a pile of bricks progressing to become a house, but something more like a million piles of bricks, wires, doors, glass panes, pipes, floor boards and electrical wires gradually progressing to become a city as organized as New York City, without any visible builders being around.
Wallingford then goes into repeating a silly old fiction that biologists have been telling for decades, even though many other biologists have been scolding them for doing that, and saying that the story is just plain false. The fiction is the false claim that genes control development. As soon as DNA and the genetic code was discovered, biologists started telling us the lie that DNA or it genes have some kind of blueprint, recipe or program for making a human body. We were told this lie for 70 years. The claim was groundless, because DNA does not have any specification at all of how to make a human body or any of its organs or any of its cells or any of the organelles that make up such cells. DNA and its genes do not even specify how to make the protein complexes that make up organelles. Indeed, DNA does not even fully specify how to make the protein molecules in the human body. DNA and its genes merely specify low-level chemical information such as the sequence of amino acids that is the starting point of a DNA molecule.
Wallingford states this big fiction about genes by stating this: "This process of body sculpting is called embryonic development, and it is a symphony of cells and tissues conducted by genetics, biochemistry and mechanics." He later states the same fiction by claiming that all animals have a "genetic toolkit to guide development," and the equally false claim that "genes direct the inheritance of traits from one generation to the next." Genes are mindless inert chemicals that don't have any specification about how to make either cells or anything bigger than cells, so it is untrue to claim that morphogenesis occurs because genes act like symphony conductors or like agents that are guiding development or directing inheritance. Wallingford could have spoken carefully and truthfully by stating that organisms have a genetic toolkit that is used in the enormously complex process of development, and by stating that genes affect the inheritance of traits. But by claiming that a genetic toolkit guides development, he stated something as false as claiming that the toolbox of a construction crew guides the construction of an apartment building.
By the use of the phrase "body sculpting" Wallingford was guilty of an extremely misleading phrase tending to make you think that the arising of a human body is a billion times simpler affair than it is. Given the human body's vast organization with so many different levels of hierarchical organization, everywhere requiring the most careful arrangement of trillions of atoms, calling the arising of a human body from a zygote an act of "sculpting" is as misleading as claiming that at a shipyard the construction of a nuclear-powered aircraft carrier is an example of mere metal sculpting.
Wallingford has a long article to fill up about human development, the arising of a full human body from a speck-sized zygote. But he has no credible tale to tell of how that happens, other than the old wives' tale fiction that genes guide development. So he fills up his article with mostly digressions. He goes into a long discussion of the history of human thinking about human development.
Later he discusses some weird experiments involving scientists fiddling with stem cells and developing organisms. He tries to insinuate that such fiddling sheds some light on how the human form originates, but fails to substantiate such an insinuation.
Are the experiments of developmental biologists this lame?
Developmental biologists such as Wallingford typically try to fool us into thinking that the human body is something vastly simpler than it is. So, for example, Wallingford gives us this extremely misleading language: "We’ve pondered embryos for thousands of years, in part because they spark our inherent wonder; theirs is the ultimate emergent property." An embryo is a very high state of living and growing organization, not a property. A property is something simple that can be expressed as a single number (something like mass, length, width, height and depth).
Wallingford misleads us some more by stating this:
"Science can tell us how the human embryo develops, and it is an undisputed certainty that embryos develop progressively, building complexity and identity only over time. But there is no scientific consensus on when during that progression ‘life’ begins."
No, scientists do not understand how the human embryo develops (in the sense of being able to explain adequate physical causes of such a thing); and almost every biologist agrees that life exists at the very earliest stage of development, as soon as a zygote starts splitting up into multiple cells. Cell reproduction very obviously requires life. An embryo is very complex from the beginning, so rather than it being an "undisputed certainty" that an embryo becomes complex "only over time," such a claim is a falsehood that Wallingford is teaching.
The progression from a speck-sized zygote to the vast organization of the human body is a miracle of coordinated construction a thousand miles over the heads of biologists. Wallingford has no credible tale to tell of how the process of development occurs, his misleading claims about genes "guiding" and "conducting" and "directing" such a process being no credible tale at all. Lacking any truthful story of how the marvel of human development can occur, all that Wallingford can do is to distract us with digressions, and try to make a developing human body sound like something a billion times less impressive than it is. So he has engaged in shadow-speaking, trying to make something sound like the mere slightest shadow of itself. He tries to suggest an embryo is a mere "property" or something that isn't complex at its beginning or something like a mere arrangement of bricks, or maybe something that is not even alive, or maybe just some shape that can be achieved by a little "sculpting." Rather than engaging in language so very misleading, our biologists should start properly educating us about the vast degree of hierarchical organization in our own bodies, and why every human body is a state of enormously dynamic physical organization far more impressive than any object humans have constructed. There's a corporation that knew how to make the 747 jet from raw materials, but there is not a nation or corporation in the world that could come anywhere close to constructing a viable human being from mere chemical raw materials.
The public will have been properly educated about biology when you can tell the average person "you have more than 20,000 types of complex inventions in your body," and that person responds by saying, "yes, of course, you mean all the different types of protein molecules in my body" rather than saying, "what are you talking about -- that can't be right." The public will have been properly educated when the average man may hear someone claiming that genes direct the construction of a human body, and that person replies by saying something like "that is as ridiculous as claiming that my shopping list directs the US government."
The correct relation between DNA and the different levels of organization in a human body is illustrated in the diagram below. The black bar makes it clear that none of the seven most complex levels of organization is specified by DNA or genes.
The amount of organization in the human body can be compared to the amount of organization in a book series such as the seven books in the best-selling Harry Potter series of children's books. Here is the hierarchical organization needed to make that book series: pixels are organized into characters or letters, and letters are organized into words, and words are organized into sentences, and sentences are organized into paragraphs, and paragraphs are organized into chapters, and chapters are organized into books, and books can be organized into a book series such as the Harry Potter series. That's seven levels of organization higher than mere pixels. In the human body there are eight levels of purposeful organization higher than the mere polypeptide sequences (chains of amino acids) specified by DNA. These are the eight levels:
- Polypeptide sequences are organized into folded 3D protein molecule shapes not specified in DNA.
- Protein molecules are organized into protein complexes.
- Protein complexes are organized into organelles.
- Organelles are organized into cells.
- Cells are organized into tissues.
- Tissues are organized into organs.
- Organs are organized into organ systems.
- Organ systems and a skeletal system are organized into a human body.
Now imagine if someone tried to explain the origin of the Harry Potter series by imagining someone merely using an ink sprayer, something that only explains the appearance of ink pixel dots, not the seven additional levels of purposeful organization needed to make that book series. That would be very ridiculous. Spraying with an ink sprayer bottle does not author a new book series. It's even more ridiculous to try and explain a human body by appealing to DNA and its genes. To make a book series you need seven levels of purposeful organization above mere pixel dots, but to make a human body you need eight levels of purposeful organization above the mere polypeptide sequences specified by DNA. "DNA makes your body" claims are therefore more ridiculous than someone trying to convince you that the Harry Potter series of books originated by a blindfolded spraying with an ink sprayer.
Appendix; Since the lie that DNA is a blueprint or program or recipe for building bodies has so often been told, I will need to cite again a list I have compiled of distinguished scientists and other PhD's or MD's who have told us such an idea is untrue.
- On page 26 of the recent book The Developing Genome, Professor David S. Moore states, "The common belief that there are things inside of us that constitute a set of instructions for building bodies and minds -- things that are analogous to 'blueprints' or 'recipes' -- is undoubtedly false."
- Biologist Rupert Sheldrake says this "DNA only codes for the materials from which the body is constructed: the enzymes, the structural proteins, and so forth," and "There is no evidence that it also codes for the plan, the form, the morphology of the body."
- Describing conclusions of biologist Brian Goodwin, the New York Times says, "While genes may help produce the proteins that make the skeleton or the glue, they do not determine the shape and form of an embryo or an organism."
- Professor Massimo Pigliucci (mainstream author of numerous scientific papers on evolution) has stated that "old-fashioned metaphors like genetic blueprint and genetic programme are not only woefully inadequate but positively misleading."
- Neuroscientist Romain Brette states, "The genome does not encode much except for amino acids."
- In a 2016 scientific paper, three scientists state the following: "It is now clear that the genome does not directly program the organism; the computer program metaphor has misled us...The genome does not function as a master plan or computer program for controlling the organism; the genome is the organism's servant, not its master.
- In the book Mind in Life by Evan Thompson (published by the Belknap Press of Harvard University Press) we read the following on page 180: "The plain truth is that DNA is not a program for building organisms, as several authors have shown in detail (Keller 2000, Lewontin 1993, Moss 2003)."
- Developmental biologist C/H. Waddington stated, "The DNA is not a program or sequentially accessed control over the behavior of the cell."
- Scientists Walker and Davies state this in a scientific paper: "DNA is not a blueprint for an organism; no information is actively processed by DNA alone...DNA is a passive repository for transcription of stored data into RNA, some (but by no means all) of which goes on to be translated into proteins."
- Geneticist Adam Rutherford states that "DNA is not a blueprint," a statement also made by biochemistry professor Keith Fox.
- "The genome is not a blueprint," says Kevin Mitchell, a geneticist and neuroscientist at Trinity College Dublin, noting "it doesn't encode some specific outcome."
- "DNA cannot be seen as the 'blueprint' for life," says Antony Jose, associate professor of cell biology and molecular genetics at the University of Maryland, who says, "It is at best an overlapping and potentially scrambled list of ingredients that is used differently by different cells at different times."
- Sergio Pistoi (a science writer with a PhD in molecular biology) tells us, "DNA is not a blueprint," and tells us, "We do not inherit specific instructions on how to build a cell or an organ."
- Michael Levin (director of a large biology research lab) states that "genomes are not a blueprint for anatomy," and after referring to a "deep puzzle" of how biological forms arise, he gives this example: "Scientists really don’t know what determines the intricate shape and structure of the flatworm’s head."
- Ian Stevenson M.D. stated "Genes alone - which provide instructions for the production of amino acids and proteins -- cannot explain how the proteins produced by their instructions come to have the shape they develop and, ultimately, determine the form of the organisms where they are," and noted that "biologists who have drawn attention to this important gap in our knowledge of form have not been a grouping of mediocrities (Denton, 1986; Goldschmidt, 1952; B. C. Goodwin, 1985, 1988, 1989, 1994; Gottlieb, 1992; Grasse, 1973; E. S. Russell...Sheldrake, 1981; Tauber and Sarkar, 1992; Thompson, 1917/1942)."
- Biologist B.C. Goodwin stated this in 1989: "Since genes make molecules, genetics...does not tell us how the molecules are organized into the dynamic, organized process that is the living organism."
- An article in the journal Nature states this: "The manner in which bodies and tissues take form remains 'one of the most important, and still poorly understood, questions of our time', says developmental biologist Amy Shyer, who studies morphogenesis at the Rockefeller University in New York City."
- Timothy Saunders, a developmental biologist at the National University of Singapore says, "Fundamentally, we have a poor understanding of how any internal organ forms.”
- On the web site of the well-known biologist Denis Noble, we read that "the whole idea that genes contain the recipe or the program of life is absurd, according to Noble," and that we should understand DNA "not so much as a recipe or a program, but rather as a database that is used by the tissues and organs in order to make the proteins which they need."
- A paper by Stuart A. Newman (a professor of cell biology and anatomy) discussing at length the work of scientists trying to evoke "self-organization" as an explanation for morphogenesis states that "public lectures by principals of the field contain confidently asserted, but similarly oversimplified or misleading treatments," and says that "these analogies...give the false impression that there has been more progress in understanding embryonic development than there truly has been." Referring to scientists moving from one bunk explanation of morphogenesis to another bunk explanation, the paper concludes by stating, "It would be unfortunate if we find ourselves having emerged from a period of misconceived genetic program metaphors only to land in a brave new world captivated by equally misguided ones about self-organization."
- Referring to claims there is a program for building organisms in DNA, biochemist F. M. Harold stated "reflection on the findings with morphologically aberrant mutants suggests that the metaphor of a genetic program is misleading." Referring to self-organization (a vague phrase sometimes used to try to explain morphogenesis), he says, "self-organization remains nearly as mysterious as it was a century ago, a subject in search of a paradigm."
- Writing in the leading journal Cell, biologists Marc Kirschner, John Gerhart and Tim Mitchison stated, "The genotype, however deeply we analyze it, cannot be predictive of the actual phenotype, but can only provide knowledge of the universe of possible phenotypes." That's equivalent to saying that DNA does not specify visible biological structures, but merely limits what structures an organism can have (just as a building parts list merely limits what structures can be made from the set of parts).
- At the Stack Exchange expert answers site, someone posted a question asking which parts of a genome specify how to make a cell (he wanted to write a program that would sketch out a cell based on DNA inputs). An unidentified expert stated that it is "not correct" that DNA is a blueprint that describes an organism, and that "DNA is not a blueprint because DNA does not have instructions for how to build a cell." No one contradicted this expert's claim, even though the site allows any of its experts to reply.
- A paper co-authored by a chemistry professor (Jesper Hoffmeyer) tells us this: "Ontogenetic 'information,' whether about the structure of the organism or about its behavior, does not exist as such in the genes or in the environment, but is constructed in a given developmental context, as critically emphasized, for example, by Lewotin (1982) and Oyama (1985)."
- Biologist Steven Rose has stated, "DNA is not a blueprint, and the four dimensions of life (three of space, one of time) cannot be read off from its one-dimensional strand."
- Jonathan Latham has a master's degree in Crop Genetics and a PhD in virology. In his essay “Genetics Is Giving Way to a New Science of Life,” a long essay well worth a read, Latham exposes many of the myths about DNA. Referring to "the mythologizing of DNA," he says that "DNA is not a master controller," and asks, "How is it that, if organisms are the principal objects of biological study, and the standard explanation of their origin and operation is so scientifically weak that it has to award DNA imaginary superpowers of 'expression'” and 'control' to paper over the cracks, have scientists nevertheless clung to it?"
- An interesting 2006 paper by six medical authorities and scientists tells us that "biochemistry cannot provide the spatial information needed to explain morphogenesis," that "supracellular morphogenesis is mysterious," and that "nobody seems to understand the origin of biological and cellular order," contrary to claims that such order arises from a reading of a specification in DNA.
- Keith Baverstock (with a PhD in chemical kinetics) has stated "genes are like the merchants that provide the necessary materials to build a house: they are neither the architect, nor the builder but, without them, the house cannot be built," and that "genes are neither the formal cause (the blueprint), nor the efficient cause (the builder) of the cell, nor of the organism."
- Evolutionary biologist Richard Lewontin stated, "DNA is not self-reproducing; second, it makes nothing; and third, organisms are not determined by it." Noting that "the more accurate description of the role of DNA is that it bears information that is read by the cell machinery," Lewontin lamented the "evangelical enthusiasm" of those who "fetishized DNA" and misspoke so that "DNA as information bearer is transmogrified into DNA as blueprint, as plan, as master plan, as master molecule." In another work he stated "the information in DNA sequences is insufficient to specify even a folded protein, not to speak of an entire organism." This was correct: DNA does not even specify the 3D shapes of proteins, but merely their sequence of amino acids.
- In 2022 developmental biologist Claudio D. Stern first noted, "All cells in an organism have the same genetic information yet they generate often huge complexity as they diversify in the appropriate locations at the correct time and generate form and pattern as well as an array of identities, dynamic behaviours and functions." In his next sentence he stated, "The key quest is to find the 'computer program' that contains the instructions to build an organism, and the mechanisms responsible for its evolution over longer periods." Since this was written long after the Human Genome Project had been completed, he thereby suggested that no such instruction program had yet been discovered in the genome (DNA).
- A 2024 article says, "MartÃnez Arias, 68, argues that the DNA sequence of an individual is not an instruction manual or a construction plan for their body...The Madrid-born biologist argues that there is nothing in the DNA molecule that explains why the heart is located on the left, why there are five fingers on the hand or why twin brothers have different fingerprints."
