Developmental biology is the branch of biology studying the process by which an organism progresses from a speck-sized state of a newly fertilized zygote to a full adult state that is vastly more organized and much larger. The Quanta Magazine article here tries to give us some sound bites suggesting that developmental biologists are making progress. But inadvertently the article is rather much a portrait of developmental biology in disarray, not getting much of anywhere, without any convincing story to tell for how marvels of biological organization occur. There's a little halfhearted mention of chemicals, a little halfhearted mention of physics, and nothing that adds up to a hundredth of an explanation of how vastly organized human bodies could arise from the tiny speck-sized simplicity of a newly fertilized zygote.
Over the past few decades we have seen these common elements in these types of articles and the papers of developmental biologists:
(1) Again and again, words will be carefully chosen to try to make the problem of morphogenesis sound a billion times simpler than it is. For example, someone will talk about a problem of the origin of "form" or "shape." The problem is vastly bigger than that. It is the problem of explaining why fantastically organized structures appear, with so many levels of very high organization. That is a problem almost infinitely bigger than the problem of explaining how human-shaped bodies arise.
(2) Again and again, appeals are made to "patterns," as if an organism's body was a mere pattern. A human body is something almost infinitely more impressive than some mere pattern. A human body is a work of the most enormous dynamism, with endless continuous purposeful activity of the most vast complexity, much of it involving the breakdown of old cells and old proteins, and their continual replacement with new cells and new proteins. Even the types of cells that last for decades continually have their components broken down and replaced, like some skyscraper being continuously remodeled.
A Google Gemini infographic
(3) Again and again, dubious claims are made that some tiny little thing has been explained, often with some kind of mention of physics or chemistry. Almost all of the claims fail to be well-replicated scientific results. An example is the unfounded claim that there are "morphogen gradient" chemicals that tell cells where to go to. For a long discussion of why this claim has no real explanatory value and is also not well grounded in observations, see my post here.
(4) The explanatory sound bites given made are ever-changing. For decades biologists told us the bogus story line that the human body arises because of a blueprint in DNA (despite the lack of any such anatomical blueprint in DNA). But the Quanta Magazine article ends with this statement, which sings a different tune:
“ 'We used to think if we just studied the genome with more and more depth and rigor, all of this would be clear,' Shyer said, but 'the answers to the important questions might not be at the level of the genome.' Once it seemed that developmental decisions were made through the interplay of genes and their products within cells, but the emerging truth is that 'the decision-making can be happening outside of the cell, through the physical interactions of cells with each other.' ”
You do not explain how cells know where to go in the developing body or how to progress from vastly simpler states by using the vague wooly phrase "the physical interactions of cells with each other." If we don't understand how cells are able to go to the right places in the body (as if they had some target destination knowledge they do not have), we do not explain such a thing by imagining such cells are interacting with other cells that also should not have such knowledge of the proper destinations of cells. And you don't get "decision-making" from "physical interactions"; you get decision-making from a mind.
(5) There is an abundant use of imprecise wooly phrases and poorly defined terms, such as "morphogens" (a term defined in many different ways) and "the physical interactions of cells with each other."
(6) Again and again, we will read the use of spurious action verbs in which it is unreasonably claimed that mindless information-free things "guide" or "direct" things. An example is when the Quanta Magazine article claims that "physical tensions within an embryo set up patterns that guide growth."
(7) Again and again, we hear about meaningless unimpressive experiments that are described in glowing terms, as if some great insight was gained. An example may be found in the Quanta Magazine article here when we read about some silly experiment in which scientists "removed the skin from a chicken embryo and disintegrated the tissue to pull apart the cells," putting the cells into a petri dish, and adding some chemical. They then observed the cells form a shape that is described as a ring shape (even though it does not look like a ring at all). This unimpressive result is described in the most glowing terms in the Quanta Magazine article, as if it provides some great insight. We see three pictures, and the third picture hardly looks any more organized than the first. But the result is described glowingly as evidence for "self-organization." Scientists are deluding themselves if they get excited about such results.
Another example of this is the Quanta Magazine article here. Besides the unsolved problem of how cells end up in the correct positions in the body (not at all solved by the socially constructed myth of morphogen gradients), there is the problem of how simple stem cells turn into 200 types of cells in the human body, most of which are many, many times more organized and complex than such stem cells. This is the problem of cellular differentiation. The Quanta Magazine article above offers no answer to this great mystery. It merely discusses scientists fooling around with artificial methods of making cells change their color.
To get some revealing glimpses of how "lost in the woods" efforts in developmental biology are, there's another place we can look other than Quanta Magazine. We can look in the grant query tool of the National Science Foundation, which you can find here. Using "morphogenesis" as the search term, we can find some of the projects that have been granted lots of money to research morphogenesis.
One such project is the project described here. It has the very general title "General Mechanisms of Morphogenesis on Multiple Scales." The project was awarded $924,000. Below are some "lost in the woods" elements we read:
(1) Morphogenesis (properly defined as the process by which a speck-sized zygote progresses to become the full organizational reality of a new-born organism or adult organism) is senselessly described in the project abstract as "the process of biological shape formation." When this kind of shadow-speaking nonsense occurs, someone is childishly trying to make the problem of explaining the progression from a one-celled zygote to a full organism look like a problem enormously simpler than it is. A human body is something almost infinitely more than just a shape. A human body is a state of vast hierarchical organization, in which fairly simple chemicals are organized into many thousands of types of very organized and functional protein molecules, different types of protein molecules are organized into very many types of protein complexes so complex they are often called molecular machines, protein complexes and individual proteins are organized into organelles, organelles are organized into 200 types of cells, cells are organized into tissues, tissues are organized into organs, and organs are organized into organ systems, with sky-high levels of fine-tuned biochemistry required everywhere for such things to work. Calling that level of organization "a shape" is like saying that a million-volume library is "some paper with ink marks on it."
(2) The second sentence of the research project abstract has this piece of vacuous or misleading hand-waving: "Recent discoveries in this interdisciplinary field have established the importance of mechanical interactions that guide growing tissues into diverse shapes and forms of adult organisms." We do not know how the enormous organization of a full human body arises from a speck-sized zygote, and no real progress has occurred in solving this problem. Claiming that "mechanical interactions" are something that "guide" this process is as vacuous as trying to explain the origin of a 100-story skyscraper by saying that "construction actions guide the building of the building." Equally vacuous hand-waving occurs later in the research project abstract when the claim is made that " patterns of tissue growth define the shapes of animal limbs," a claim as empty as the claim that "patterns of building define how the building arises."
(3) The second paragraph of the research project abstract is just as bad and misleading. We have an appeal to "active mechanical self-organization of tissues" (a vacuous hand-waving phrase) and an appeal to the false claim that developmental biologists have long told, the fiction that development occurs because instructions for how to build a body are read from DNA. This time that falsehood is told by the claim that there are "genetically encoded developmental signals that guide morphogenesis." There is no robust evidence for such signals, and DNA and its genes do not have any specification of how to build a human body or any of its organs or any of its cells. DNA and its genes do not even have any specification of how to make any of the organelles from which cells are constructed. DNA contains only low-level chemical information such as which sequence of amino acids makes up a particular type of protein molecule.
(4) By the third paragraph we learn that the project will try to make things a million times easier not just by defining morphogenesis as the mere arising of a shape, but also by restricting itself to a study of fruit flies, tiny creatures only 3 millimeters in size (one third of an inch).
When a project abstract makes statements so misleading, oversimplified and self-contradictory, showing such a childish notion of the mountainous problems of explaining morphogenesis, we should have no confidence at all that the allocated money will be wisely spent.
We have the same kind of shadow-speaking nonsense in another project awarded more than $700,000 by the National Science Foundation. It's a project (described here) with the dumb-sounding title "In-Vivo Analysis of Active Mechanical Mechanisms Driving Animal Morphogenesis." Mechanical mechanisms? That sounds like someone saying that his project is "scientifically scientific." When scientists don't understand some mystery a hundred miles over their heads, scientists often use vague and vacuous hand-waving phrases such as claiming that something is "guided" or "driven" by "mechanisms." Such assertions don't really amount to saying anything.
In the first paragraph of the project abstract, we have the same sins as the research project previously discussed. Again, the problem of explaining the arising of the vast organization and dynamism of the full body of an organism is senselessly reduced to a mere problem of explaining "shape." Again, we have the telling of the favorite falsehood of developmental biologists, this time as the untrue claim that "genes instruct form." Without giving any details, we are vaguely told that "experiments will be used to uncover the physical mechanisms of how 3D shape is dynamically encoded by 2D gene expression patterns." Again, we have the childish nonsense of trying to reduce the problem of explaining the origin of enormously organized organisms into a billion-times-easier problem of merely explaining a shape. Neither the shape nor the structure of any human body is encoded in genes, nor is the shape or the structure of any organ system, any organ or any cell or any cell organelle. "DNA as body blueprint" is the lie that many biologists keep telling, even though dozens of biologists, chemists and doctors have confessed that DNA and its genes are no blueprint or recipe or program for making a body or any of its organs or cells. You can read a bullet list of the statements of such biologists, chemists and doctors in my long post here, entitled "Why We Were Told So Often the Huge Lie That DNA Is a Specification for Building Humans."
$894,000 has been allocated to this project, which we should have little confidence in, based on the misstatements in its abstract. Anyone who thinks that the problem of explaining the progression from a speck-sized zygote to a full human body (the problem of morphogenesis) is a mere problem of explaining a shape is someone lost in the woods when it comes to understanding the unsolved problems of developmental biology.
Each of of these projects involved almost a million dollars allocated to try to help solve one of the two hardest problems of biology, and senselessly both of the projects were awarded not to people in a department of biology but to people in a department of physics. The people who wrote the abstracts for these research projects sounded like people who had never adequately studied biology.
I found one other example of this type of thing. It is the project entitled "Geometry, Genetics and Development" described on the page here. The project description starts out with a huge falsehood by stating, "Developmental biology has been immensely successful in reducing the seeming miraculous self-organization of a fertilized egg to a fetus and adult to a list of genes and the instructions for their regulation in the noncoding genome. " Nothing of the sort has occurred. DNA and its genes do not specify any of these things: how to make a full human body, how to make any organ system, how to make any organ, how to make any cell, how to make any of the organelles that make up a cell. Developmental biology has utterly failed to explain the progression from a fertilized egg to a full organism.
We are told that the research of this project will involve tiny little creatures such as C. elegans, a roundworm. We can be rather sure that no real light will be shed on human morphogenesis. No research plan is specified in any detail; but strangely the project has been awarded more than $750,000. Once again, a huge sum has been awarded to try and solve one of the two hardest problems of biology; but the money was awarded not to a department of biology but to a department of physics. Again, we have a research project abstract with a glaring falsehood, sounding like it was written by someone who had never decently studied biology.
The links I have given above to these projects will take you to pages that list scientific papers that were the end results of the millions that were allocated. An examination of those papers will be very unlikely to leave you with any feeling that physicists are capable of shedding much of any light on the great riddle of how the vast purposeful organization and ever-constructing dynamism of a human body arises from a speck-sized zygote having no specification of how to build such a body or any of its cells.
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