A deformed human is still a h IJS human. Clearly you don’t h have a clue
What if genotype predisposes, but not exactly determines, phenotype? That leaves room for epigenetic considerations, as well as changes in morphology due to stressors during development?
It requires planning
what in the world are you talking about?
Ok but there is still software running it all
I would have thought that was obvious. I’m sure TJ agrees with that.
What are you talking about? I am still waiting for the evidence that supports your claim
An example: Arabidopsis thaliana plants that have the same genotype can have very different phenotypes if the plant is exposed to mechanical stimulations during development. Different stem lengths, different branching structure, etc
This is not a purely mechanistic process; the analogy of a computer serves --there’s programming, organized around iterative inputs, there are subroutines that can kick in to take over, but in the end, you have the wisdom predesigned into the software, interacting with the hardware, totally dependent upon environmental and other factors (electricity, temperature, a person at the keyboard, even). Okay; every analogy eventually begins to break down…
@JoeG…you have been worried about PLANNING?
We are Christian Evolutionists… God plans everything.
There… now you don’t have to worry.
JoeG is an awkward cuss, but the problem of relating genotype to phenotype is well-known. It’s even a problem, now we know more about how genomes function, to unpick the genetic causes of relatively simple functions - hence the unexpectedly poor outcomes of genetic medicine from the Human Genome Project.
But using the word “phenotype” rather loads the interpretive dice - I believe the term arose in juxtaposition to “genotype” as the second side of the coin, ie it’s defined as what the genes cause.
But “form” is a much older word, encompassing the whole unified nature of a particular organism from bauplan to behaviour. The role of the cell apart from the genome in determining form was discovered long ago in Paramecium (for example), and has produced results in a number of areas - but it has been a sideline to the all-encompassing genocentric research program.
Developmental biology still has relatively few answers to the role genetics plays in embryological development. Of course genes are essentials - but that is no more proof of causality than my dependance on my library for information tells you that my books are blueprints for blog posts.
Deleting genes changes cells, yes - but delete the cell and leave the genome entire, and you’ll not get an organism at all.
Likewise, the easy assumption that we can also explain the lifestyles of creatures by their genes is throughly overturned by the study of human behaviour, and despite our specialness there is no evidence that it is any different for animals: do we really believe that the details of protein production really dictate how a swallow builds it nest?
One statistic - it seems that around 700 genes are implicated in the control of human height alone. What’s that as a proportion of coding genes? We have simply no idea of how a cell grows into a giraffe in one case, and a zebra in another. Still less, of what is actually necessary to get a giraffe or zebra from a previous form, in a successfully coordinated manner.
It’s now a truism in the behavioural sciences that “you are not your genes”. But I don’t think that’s a comment on human exceptionality, ie that we alone have free will and can overcome our genes (as even Dawkins said). It’s simply that genes appear to be acting more as a resource for a living form than as a blueprint for a phenotype. And clearly the phenotype cannot be both a result of gene expression and a cause of it.
The main conceptual difference, then, between “phenotype” and “form” is that the former is merely the sum of atomistic chemical reactions (making evolution a piecemeal atomistic process), whereas “form” is a holistic understanding that there is a unity governing the whole organism. And that would lead, logically, to a holistic form of evolution, in which genes play just a partial role.
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That sounds like it supports my claim
I’m not sure what your claim even is. Bevause you are vague and incoherent. And I have no interest in continuing this conversation with you. @JoeG
Edit: if you are referring to my plant example I never denied the environment can influence phenotype. It’s a combination of genotype and environmental factors. This gets into things like phenotypic plasticity.
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But it will never become a rose bush nor any other type of plant
Incorrect. It is very possible through phenotypic and genetic accommodation. An environmental input can cause a reorganization of the phenotype which can produce novel variable phenotypes (phenotypic accommodation). The new phenotypes provide material for selection and if it is selected for they could become prevalent in the population. And this could lead to genetic accommodation. Adaptive evolution that involves changes in the genetic structure of the population.
I recommend the work of West-Eberhard and Pigliucci. Peace
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What? Your position of “same genes used differently” is as vague and incoherent as it gets. Which genes? How were they used differently and what changes did they affect?
My position is we do not know what determines form/ body plan. This is supported by Drs Denton, Sermonti and Wells. And no one has been able to demonstrate otherwise.
BlockquoteTo understand the challenge to the “superwatch” model by the erosion of the gene-centric view of nature, it is necessary to recall August Weismann’s seminal insight more than a century ago regarding the need for genetic determinants to specify organic form. As Weismann saw so clearly, in order to account for the unerring transmission through time with precise reduplication, for each generation of “complex contingent assemblages of matter” (superwatches), it is necessary to propose the existence of stable abstract genetic blueprints or programs in the genes- he called them “determinants”- sequestered safely in the germ plasm, away from the ever varying and destabilizing influences of the extra-genetic environment.
Such carefully isolated determinants would theoretically be capable of reliably transmitting contingent order through time and specifying it reliably each generation. Thus, the modern “gene-centric” view of life was born, and with it the heroic twentieth century effort to identify Weismann’s determinants, supposed to be capable of reliably specifying in precise detail all the contingent order of the phenotype. Weismann was correct in this: the contingent view of form and indeed the entire mechanistic conception of life- the superwatch model- is critically dependent on showing that all or at least the vast majority of organic form is specified in precise detail in the genes.
Yet by the late 1980s it was becoming obvious to most genetic researchers, including myself, since my own main research interest in the ‘80s and ‘90s was human genetics, that the heroic effort to find information specifying life’s order in the genes had failed. There was no longer the slightest justification for believing there exists anything in the genome remotely resembling a program capable of specifying in detail all the complex order of the phenotype. The emerging picture made it increasingly difficult to see genes as Weismann’s “unambiguous bearers of information” or view them as the sole source of the durability and stability of organic form. It is true that genes influence every aspect of development, but influencing something is not the same as determining it. Only a small fraction of all known genes, such as the developmental fate switching genes, can be imputed to have any sort of directing or controlling influence on form generation. From being “isolated directors” of a one-way game of life, genes are now considered to be interactive players in a dynamic two-way dance of almost unfathomable complexity, as described by Keller in The Century of The Gene- Michael Denton “An Anti-Darwinian Intellectual Journey”, Uncommon Dissent (2004), pages 171-2
and Dr Sermonti, Chapter VI “Why is a Fly not a horse?” (same as the book’s title)
Blockquote”The scientist enjoys a privilege denied the theologian. To any question, even one central to his theories, he may reply “I’m sorry but I do not know.” This is the only honest answer to the question posed by the title of this chapter. We are fully aware of what makes a flower red rather than white, what it is that prevents a dwarf from growing taller, or what goes wrong in a paraplegic or a thalassemic. But the mystery of species eludes us, and we have made no progress beyond what we already have long known, namely, that a kitty is born because its mother was a she-cat that mated with a tom, and that a fly emerges as a fly larva from a fly egg.”
Sermonti also talks about how sexual reproduction and sexual selection put an end to Common Descent:
BlockquoteSexuality has brought joy to the world, to the world of the wild beasts, and to the world of flowers, but it has brought an end to evolution. In the lineages of living beings, whenever absent-minded Venus has taken the upper hand, forms have forgotten to make progress. It is only the husbandman that has improved strains, and he has done so by bullying, enslaving, and segregating. All these methods, of course, have made for sad, alienated animals, but they have not resulted in new species. Left to themselves, domesticated breeds would either die out or revert to the wild state—scarcely a commendable model for nature’s progress.
(snip a few paragraphs on peppered moths)
Blockquote Natural Selection, which indeed occurs in nature (as Bishop Wilberforce, too, was perfectly aware), mainly has the effect of maintaining equilibrium and stability. It eliminates all those that dare depart from the type—the eccentrics and the adventurers and the marginal sort. It is ever adjusting populations, but it does so in each case by bringing them back to the norm. We read in the textbooks that, when environmental conditions change, the selection process may produce a shift in a population’s mean values, by a process known as adaptation. If the climate turns very cold, the cold-adapted beings are favored relative to others.; if it becomes windy, the wind blows away those that are most exposed; if an illness breaks out, those in questionable health will be lost. But all these artful guiles serve their purpose only until the clouds blow away. The species, in fact, is an organic entity, a typical form, which may deviate only to return to the furrow of its destiny; it may wander from the band only to find its proper place by returning to the gang.
Blockquote
Everything that disassembles, upsets proportions or becomes distorted in any way is sooner or later brought back to the type. There has been a tendency to confuse fleeting adjustments with grand destinies, minor shrewdness with signs of the times.
Blockquote It is true that species may lose something on the way—the mole its eyes, say, and the succulent plant its leaves, never to recover them again. But here we are dealing with unhappy, mutilated species, at the margins of their area of distribution—the extreme and the specialized. These are species with no future; they are not pioneers, but prisoners in nature’s penitentiary.
Dr Wells, whose field is developmental biology, tells us that there are physical factors within the egg that also contribute to the developmental process
What is incorrect? What is possible through phenotypic and genetic accommodation and what is the evidence for it?
I am wasting my quota on you. Please be specific and provide the evidence that supports your claims
I have provided the evidence on multiple occasions and even provided some examples. Even recommended people’s work. You have chose to ignore it. Do not tag me in anything else
No, you have not provided any evidence just your say-so. Your examples do not support your claim that form/ body plan is determined by genomes and the way they bare regulated.
I have read Sean Carroll and Neil Shubin, both experts in the field of evo evo. They can’t even provide the evidence you claim exists.
But Joe, even if your description is the better one… it does not lead to “Only Special Creation”.
What it does might reveal the footnotes for how Common Descent can be more subtle than many realize. But it certainly doesn’t move the discussion from God-led Speciation to Young Earth scenarios (or Old Earth scenarios involving ONLY special creation).