Pro-Life Academy Every Tuesday and Thursday.
Okay gentle scholars, a double-dip today in two separate posts. First, a final word about diversity in gametes.
If it seems that I’m going back and adding details on in layers, go to the head of the class!!
One of the great difficulties students encounter in studying meiosis is that there are a blizzard of details and new vocabulary that cause one to give up hope half-way through. It’s best to spread this material out in bite-sized pieces.
Building on all that we have seen, let’s go back to the beginning of meiosis where the homologous pair of chromosomes undergoes DNA synthesis. And let’s recall that what makes a pair of chromosomes homologous is that they have the same genes at the same location from top to bottom along the chromosome. Here comes the diversity.
A gene, recall, is a stretch of DNA whose nucleotide sequence is a code for building a certain protein. Now, let’s say that the first gene on a chromosome is the gene coding for hair color. We’ll call that gene the hair color gene. However, there are blondes, brunettes, raven black hair, and red heads. So clearly, not all hair color genes are the same. There are alternative forms of the hair color gene, as there are alternative forms of a great many genes. We call these alternative forms of genes alleles.
Some alleles are mainifest or what we call expressed in a dominant manner. That means if a dominant allele and a recessive allele are inherited for hair color, the dominant allele gets expressed.
Let’s consider hair color. My mother was a strawberry blonde. Dad had brown hair. That means mom gave me a recessive allele and dad gave me a dominant allele. Therefore, what’s left of your professor’s (rapidly) graying hair is brown. When the homologous pair of chromosomes contains a mixed pairing of alleles, the dominant allele gets expressed. Brown and Black are Dominant. Blonde and Red are recessive. (If the gentle scholars want a class on those pesky Punnett Squares for predicting offspring traits, let me know in the com boxes.)
Dominant alleles are designated with an upper case letter.
Recessive alleles are designated with a lower case latter.
So, as things stand we get one chromosome in a pair from mom and the other from dad. That mens that half our gametes will contain one, and half will contain the other after meiosis. But nature has a way of shuffling the genetic deck even further. It turns out that during the first phase of meiosis the chromosomes from mom and dad in a homologous pair overlap or what we call cross over and exchange pieces of DNA. Such chromosomes where recombination of alleles has occurred are called recombinant DNA.
Here are two videos showing this process. The first video is shorter and more generalized. The second is a little longer with more specifics.
Still with me here?
Now for the payoff.
First, imagine meiosis without crossing over and consider the possibility for different gametes.
Half of the gametes could contain all 23 chromosomes from my mother, the other half all 23 from my father.
Some could contain 22 chromosomes from my mother, 1 from my father.
Some could contain 21 chromosomes from my mother 2 from my father.
etc.
These can occur in any of a mind-numbing series of combinations.
NOW add to that the crossing over and exchange of alleles in each of the chromosomes.
Add to that the fact that crossing over and exchange of alleles on any given chromosome pair occurs at many different loci means almost infinite possibilities for genetically unique gametes in any given parent. Then, the offspring are the result of two gametes from such wildly different genetic backgrounds.
The result is a genetic uniqueness never duplicated in nature, save for identical twins. Even among identical twins, there are differences in appearance, personality and longevity.
So human individuality is not the result of one’s collected neurological experiences, but is written in our genome. It is this unique genetic identity that controls neurological development and function. To the extent that behaviors have a genetic etiology, these instructions are present from the moment of conception.
Therefore individuality is ultimately, at the biological level, a function of genetic inheritance.
That begins at conception. It is never repeated again.
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Photo via johnlarroquetteproject.com
The eye-opener for me is the pairs. I always understood that each pair of chromosomes included one from the mother, one from the father. What is shown here is that there is a pair from the mother, AND a pair from the father, and that these two pairs, each control the same sets of genes for the same genetic expressions. Do I have that right?
You are an excellent biology teacher Gerard, and you know your field very well.
As to the last three paragraphs however, which are more philosophical than empirical, I would have said that genetic identity is expressed in the neurological development of a fully grown human organism and influences the behavior of the resulting individual. To attribute human individuality to the genes alone comes dangerously close to the speculative science fiction of Richard Dawkins. (Other than my specific back-handed reference here, I expect we would be in general agreement about the worth of Dawkins’s thinking).
SJ,
Allow me to clear up some confusion. What you see here is a single pair of chromosomes.
The purple from mom, the blue from dad. They have undergone DNA synthesis (replication) and the carbon copies are joined to each other at the center.
I don’t mind coming dangerously close to Dawkins, or even sitting in his lap, so to speak, in making a pro-life apologia. If the secularists want God out of the picture, fine with me. It actually makes my job easier without having the God of the universe on my shoulder.
Forget God for now.
All we have is biology.
It’s simply stupid and absurd for a biologist to argue that personal identity is tied up in the collective functions of the brain, as the brain is the central organizing reality of the organism. It isn’t.
Long before there is a brain, it is the cell nucleus that directs organismal development, beginning with the single-celled zygote.
It is the nucleus that directs the brain architecture with no two brains wired exactly the same.
It is the cell nucleus that directs brain biochemistry and associated function. The sensory inputs from the world are filtered through a brain sculpted by the cell nuclei and interpreted in a biochemical milieu established by the cell nuclei.
Those sensory inputs are filtered, interpreted, stored, retrieved, collated, processed for response all in an environment created at the direction of the cell nuclei and their unique set of instructions.
Biologically, it is the cell nucleus, present at conception, that directs who we are and how we respond to the world.
A Christian can make the case for God, grace, soul, etc.
The atheist is stuck with pure biology.
The atheist is stuck with the cell nucleus as the central organizing reality of the human organism.
That means the person is present from birth. All other experiences are simply environmental accretions. Ascribing individuality to the accretions makes experience the personal entity, and not the organism.
We’re better off with God.
We can agree that we’re better off with God.
But I disagree that a unique molecular signature defines a human being. It is merely the chemical foundation for a human being to be formed. A blueprint is not a building.
“But I disagree that a unique molecular signature defines a human being.”
Nor are we claiming that it does. This is nothing more than a convenient strawman that you are tossing around. Try addressing the real pro-life position next time.
“It is merely the chemical foundation for a human being to be formed.”
While the “molecular signature” you speak of is present in the human embryo, it is by no means the only thing present. The embryo is already a self-integrating entity, a whole living member of the species Homo sapiens; in other words, a human being.
“But I disagree that a unique molecular signature defines a human being. It is merely the chemical foundation for a human being to be formed. A blueprint is not a building.”
ah but a blueprint contains NOTHING that IS the building. It is a set of instructions, that is all.
However, with human beings, the blueprint instructs and directs itself, making it’s own building materials. A house blueprint can NEVER do this. It contains only the instructions. It cannot on it’s own, act on those instructions.
Therefore, your analogy doesn’t hold. 😦 Sorry.
SJ,
I understand your analogy, but I believe that it does not hold. Genomics is more than the study of static blueprints. Genomics is a dynamic field of molecules interacting where DNA serves not only as blueprint but architect and construction foreman.
The nucleus itself regulates what molecules may enter and exit in the same exact manner one gains entry to a bank lobby after hours with an ATM card. The nucleus actually has doors with “card readers’ where a molecule seeking entry or exit must have the appropriate signal recognition sequence.
That’s why I took pains to describe the function of individuality at the biological level in terms of nuclear function, of genomic function and not mere allelic variation, though that plays a significant role.
Further, why stop short at the brain and its associated functions as the repository of individual identity? Such neurological realities, as I’ve explained, are written in the genome itself. Only abortion makes us extrapolate further out from fertilization to an arbitrary set of criteria to draw the line as to organismal identity and its intrinsic dignity.
Only abortion.
“Only abortion.”
There is also embryo destructive research, which has the potential to be much worse than abortion. Check this out:
http://lifeissues.net/writers/agl/agl_01stemcelldebate.html
Gerard, I decided to take a day or so mulling this over before responding. There is a chicken and egg question in your statement that “only abortion makes us extrapolate further.” Whenever a question of science is drawn into a political or social contoversy, every statement, from all sides, becomes suspect. Is X person representing Y political argument arranging the science to support their argument? Or are they modifying their argument based on the available science?
Motivation to abort, and practice of abortion, pre-dates any semblance of modern science. I see little evidence in history that anyone seized upon a new scientific discovery to say “Oh, I was wrong.” People do change their minds about, among other things, abortion, and lately your side has had better headlines on that score. But it is seldom about science, although lately it has sometimes been about the emotional impact of seeing a fetus on a sonogram. I thinks there is some validity to that — the 1973 understanding of “quickening” may have been crude, and may now be unsupportable. The boundary I approve of may have to be moved back, somewhat earlier in the rather artificial period known as second trimester.
But I don’t have to make up the distinction I advocate as a convenient excuse for abortion. Metabolic independence is a real condition, although you find it an unacceptable boundary. Cognition is a real condition, although subtle and more difficult to measure.
Cognition is not a neurological reality in the zygote. A complex series of chemical instructions is a reality in the zygote. Cognition is a neurological reality when millions of molecules have entered and exited the gateways, building up neuronic pathways which definitely do not exist in the zygote.
Only abortion motivates you to see them as one and the same thing.
What does “metabolic independence” mean, exactly, and why do you think it has any significance for determining what natural rights a human being posseses?
The ability to survive outside the womb is a technology-dependent attribute. I sure hope you are not suggesting that such an attribute has any bearing on natural rights.
It’s only a matter of time before we construct an artificial womb. At that point, we will not be able to avoid the fact that what is intended in abortion is, in most cases, to kill the baby, and not just to end the pregnancy.
I found an interesting discussion of that topic here:
http://lifeissues.net/writers/kac/kac_14artificialwombs1.html
SJ,
As always, I appreciate your cogent arguments. I do, however, see some issues within them that invite further clarification and discussion.
You state that cognition is not a neurological reality in the zygote. True in the sense that it is not a neurological reality in terms of neurons and neurotransmitters. Untrue in the sense that the zygote lacks cognition.
All living organisms, even the lowly bacterium, have an extraordinarily complex array of sensors embedded in their cell membranes. These sensors detect everything from hormones, food, acid, base, salt, water, peroxide, light, to magnetism, heat, you name it. The individual cell not only senses, but has the capacity for immediate, intermediate, and long-term responses.
This is true for organisms ranging from E. coli to the human zygote. Further, these sense systems are tied into entire regulatory networks within the cell. It’s truly fascinating material. It’s some of the stuff I love best!
I’ve posted a few posts of leading biological and medical texts all stating that a new human organism exists at the moment of fertilization. That’s science fact, not science fiction, and I place those quotes dead center in these discussions.
The new human organism, even in its single celled stage has extraordinary capacity for sensing and responding to its environment.
Forgetting God and remaining purely biological, the ability of the human organism in the configuration you and I share at our present developmental stage is nothing more than a more complex network of cells, all engaging in cellular biochemistry and physiology. What type of cognition-degree and kind-is purely arbitrary.
The texts have spoken loud and clear: A new human organism exists at conception. Period.
I also reiterate that only abortion makes one draw arbitrary boundaries regarding whether or not one is personally disposed to grant full member status in the human family to these new human organisms that biology tells us are so.
The sonogram is indeed emotionally evocative. Blessedly so, as the emotions spring from what the senses tell us in looking at those images: that the embryo and fetus are not a blob of undefined tissue. It is very much already identifiable to the layperson as human in its familiar form. Far from undefined, the senses reveal to us the wonder of life unfolding within the sanctity of the mother’s womb.
You touch on a great argument and then retreat quickly, that of the Supreme Court’s rationale based upon quickening. two decades after Roe, the science texts presented on this blog brimmed with declarations of the human identity of the embryo, beginning at the zygotic stage.
None of that matters now, nor would it have then in 1973. Seven men made up their minds and grasped at straws to justify setting into motion their American chapter of what has become the greatest holocaust ever known in human history.
I’m going to interrupt my propensity for vigorous point by point argument. Recently a woman who has been contributing to Alexandria, who is pro-life, has posted an article about her difficulties contending with many other contributors who are pro-choice. Her title is “What If I Am Wrong?” but she isn’t writing to reconsider her pro-life views. She is firm about them. She also asks a perfectly valid point, “What if you are wrong?” I offer her words, and the extensive discussion they sparked, as perhaps worthy of attention from everyone here. I referenced my participation here in responding to her.
http://aleksandreia.wordpress.com/2010/01/29/what-if-i-am-wrong/
Gerard,
“…..Untrue in the sense that the zygote lacks cognition.”
“All living organisms, even the lowly bacterium, have an extraordinarily complex array of sensors embedded in their cell membranes. These sensors detect everything from hormones, food, acid, base, salt, water, peroxide, light, to magnetism, heat, you name it. The individual cell not only senses, but has the capacity for immediate, intermediate, and long-term responses.”
“This is true for organisms ranging from E. coli to the human zygote. Further, these sense systems are tied into entire regulatory networks within the cell. It’s truly fascinating material. It’s some of the stuff I love best!”
That’s amazing! Thanks for sharing!
We do not worry over much about destroying e. coli, or paramecium, so the characteristics these cells share in common with the human zygote must not be the characteristics which make the zygote a human being.
Sensing ” everything from hormones, food, acid, base, salt, water, peroxide, light, to magnetism, heat,” needs some definition. Is the cell AWARE of these things, or is it simply programmed to respond in a certain chemical and physical way to their presence? There is a saying about not letting your left hand know what your right hand is doing. Its a figure of speech, because the hand is not aware of anything. Although there are sensory neurons in the hand, only the brain is actually aware of the sensations communicated from the hands, or able to instruct the hands, but severed hands, or severed heads, do have muscle reflexes which may spontaneously jerk around for a time, even respond to stimuli.
I am reminded of the researchers who try to establish that chimpanzees are capable of “language” and even that plants “talk to each other.” PETA supporters will have no problem with that, but I do. Human beings are qualitatively different, even without the observation that we are made in God’s own image. The genetic difference between us and a chimpanzee is around 1%. Yet somehow, that 1% makes us a wholly different quality of being. It you took a baby chimpanzee, removed its body hair with a depilatory, wrapped it in a nightgown, placed it in a crib, hugged it, fed it from a baby bottle, put educational toys all around it… it could never ever ever grow up to be human.
The more complex network of cells is precisely what differentiates us from one-celled organisms, and from less complex multi-celled organisms. Cellular biochemistry is indeed a beautiful process, but one we manipulate every day. If there is something special about the human zygote, it is precisely that it is human, not that it is a cell.
I used to have trouble imagining how there could be a one-celled organism, knowing that my heart, my liver, my skin, is made up of many cells. But, the cell itself has multiple organs within it. One could almost begin to think that the separate cells in my body are “enslaved” to a totalitarian “state.” But the cells, while complex miniatures of life, are not self-aware. Unlike a soldier in an army, who has a whole individual life to return to if not killed in combat, in service to the unit, my skin cells are unaware when they die and are sloughed off. So the zygote certainly is a living cell, and it is a human zygote, it is a specially programmed human cell, but is it a human being?
Biology in itself is a numbers game. Hundreds of ova, millions of sperm, each capable of contributing to innumerable genetic combinations which would each be unique persons, are wasted. A fair number of fertilized zygotes naturally fail to imbed in the uterine lining, or grow to a point and then spontaneously abort — often linked to some defect in the way it is growing. It is the self-aware individual life that is infinitely precious, that experiences what happens to it as 100%, not as a statistical rarity among a species of millions. For the survival of the species, no individual matters. For the self-aware individual, it’s own survival makes all the difference in the world.
To really evaluate what the sonogram tells us, I would need to see a whole series, from one week after conception to just before labor, at weekly intervals. I am reasonably certain that a flat layer of cells, containing three layers of three different cell types, would not evoke the same response to the viewer of a sonogram that an 8-month fetus would. The latter, in my view, is unquestionably a baby, by every criterion I have offered. In between… the boundary between second and third trimester may well be the wrong place to draw the line. If the sonogram series I have described exists, I am confident you would present them honestly. Merely having the rough shape of a head and limbs wouldn’t be definitive. There is a point which corresponds to what was once called “quickening,” even if it is earlier and more subtle than previously observed.
” It is the self-aware individual life that is infinitely precious, that experiences what happens to it as 100%, not as a statistical rarity among a species of millions. For the survival of the species, no individual matters. ”
Let’s say for argument I agree with you (although I don’t).
Let’s kill every living human and see if the species survives.
– obviously it won’t.
Let’s save all or some men, but kill all women except a pregnant women who just conceived yesterday, and see if the species survives.
– the species has a chance to survive if the embryo is a girl and the embryo survives long enough to be born and reproduce.
Obviously this individual embryo matters very much even though is it not self-aware.
* * *
Do you know for sure that skin cells don’t know that they are dying and going to be sloughed off? Maybe they sense that they are being crowded out by newer cells. If you sense something about yourself, we consider you self-aware. Then, in turn, we could say that the cell self-aware. Right?
SJ,
My point is that self-awareness exists in qualitatively different modes depending on the developmental stage of the animal. You are picking a more complex means of sensing and responding and suggesting that that defines what it is to be human.
Big mistake.
An organism need not exhibit all of its potential functions at any given time in order to be considered a member of the species. Such reasoning is simply not consistent with a scientific understanding of species identity.
The human organism, beginning at fertilization undergoes a series of developmental stages all the way through natural death at the age of 120 years, if the individual is lucky enough.
The organism is whole and complete in both form and function for each particular developmental stage. You pick the latter stages and arbitrarily draw a line to suggest that is what defines the human organism as such. Therein leis your error.
I think we are at an impasse. What you call a big mistake, seems to me to be common sense. What you call an arbitrary line, appears to me to be a boundary between qualitatively different states. What you call whole and complete, I call unformed potential.
However, I have no desire to impose my perspective on others. There are women who are told, your fetus may have Down’s syndrome, do you want a trisomy-21 test, who answer, no, what for, I’m going to have the baby anyway. There are couples who decide, when the wife is infected with rubella, that they are going to carry the pregnancy to term. I cannot conceive of a consistent legal standard which would authorize me or anyone to over-ride their decision, which I could accept as good law.
Accordingly, because the differences are so wide, and so impossible to resolve with any accord, I am content to let the legal standard be, leave it to the woman concerned, in consultation with any man she trusts enough to have entered into a covenant with, to make the decision. Nobody should force her hand, one way or the other. No doubt mistakes will be made, one way or the other, but we are each accountable for our own decisions.
“I think we are at an impasse.”
No, we are most certainly not at an impasse. Your claim that there is a boundary between qualitatively different states falls flat because you can’t actually define that boundary and you can’t define what that qualitative difference is.
Your last resort is to claim that, because we will never agree, we should therefore (conveniently enough for you) let the status quo stand.
No, sorry, we are not buying it.
SJ,
I do enjoy your commentary and the spirited, but civil exchanges that you have here with others. More often than not, I resist the urge to jump in because I prefer to moderate and not dominate. I’m also more interested in seeing where you guys take the conversations, so please do not interpret my silence as disinterest.
However, Dan raises a serious and excellent series of points in his post, per usual.
Regarding impasse and unformed potential:
Look, let’s be honest here. You and I are worlds apart on personhood and have acknowledged as much. But I cannot let this one escape. As the trial lawyers say, when the facts are on your side, pound the facts. When the facts are not on your side, pound the table.
You’re pounding the table here, albeit in a courtly and gentlemanly manner 😉
The facts are striking here from an embryological perspective. There is simply no ‘unformed potential’ in the manner in which you use that term. The term more appropriately indicates “developmental stages not yet achieved.”
My children, in their pre-pubescence have unformed potential. You and I are agreed on the fact that they are human persons, though they cannot reproduce or engage in much (if any) abstract reasoning-the latter being a neurodevelopmental milestone.
Thus, you do draw an arbitrary line in the sand. Science recognizes the human zygote as a distinctly new and separate human organism. I posted those many textbook quotes early on in the life of this blog to serve as a foundation for the arguments I would be making.
With the zygote being a new and separate organism, it is whole and complete in form and function for each developmental stage, until death as a senior citizen.
It is the pro-choice argument that an arbitrarily established set of developmental endpoints are (conveniently from the perspective of time window for abortion) the necessary milestones to either admit the human organismal identity of the embryo and fetus, or the personhood identity (which confers the protection of the law).
As the current law is configured under Doe v. Bolton, a woman can have an abortion at any stage of her pregnancy, right up to the due date.
I know that you do not advocate this extreme barbarity and please be assured that I would never impute that to you SJ.
But your predicates at the other end of pregnancy throw wide the door for greater harm by denying what science has declared to be so.
In the Roe v. Wade decision, the Court looked to science for guidance as to the human identity and status of the embryo and fetus. At that time, Molecular Biology itself was in its own zygotic stage. The imaging technology of ultrasounds ad fiber-optic videography simply did not exist.
Thirty-Seven years, several generations of technology, a revolution in Molecular Biology and Embryology, and 50 Million dead babies later, we live in a very different world than did the Justices of 1973.
Now, however, the arguments are not that science tells us that human organismal identity probably occurs later. Now the argument is that we simply don’t care what science says. We’ll draw our own convenient lines to salve our consciences.
Serious offer here SJ. Next year I would be honored to have you join with me and my friends in the Silent No More Awareness campaign at the Supreme Court Steps on the day of the March for Life. I honestly want you to hear their stories live and unfiltered. I want you to hear how they were lied to before the procedure, yet how they were wheeled into a recovery room filled with women weeping, whose consciences told them what they had just done.
Then dinner is on me. A very serious offer, as you are one of the few pro-choice advocates who genuinely shows an interest in engaging the data in a serious and intellectually honest manner. These women ARE the data.
God Bless
I’ve marked on the Jan 1, 2011 page of my 2010 calendar to respond to your invitation, if I have not done so sooner. Two positions I would not want to find myself in:
1) Assumed to be part of the protest against Roe v. Wade.
2) Assumed to be there counter-protesting on behalf of NARAL or Planned Parenthood.
If I am free to travel at that time, and can be there honestly as someone with firm pro-choice convictions who wants to hear what the women you refer to have to say, from their own mouths, in person, I would love to accept. I’ve lived in DC, know the area, still have my church membership in the area, and have people I could stay with.
On another recent post, I’ve gotten into a rather tangled confrontation with a couple of people about the issue of coercion. I don’t want to prejudice my ability to listen to the accounts you briefly summarized here, but at present I don’t believe the solution to women being coerced to have abortions lies in passing criminal legislation. In fact, if the emphasis of the pro-life movement shifted away from overturning Roe or reinstituting criminal penalties, we wouldn’t have much to argue about.
I’m quite aware that part of what passes for a “pro-choice” movement includes people and organizations who in practice are “pro-abortion.” I disagree. I am quite open to exploring how women can make a true choice, fully informed. We can explore the details another time, but a fanciful possiblity would be to have every Birthright and every Planned Parenthood clinic in the same building, with three entrances, and patients entering only through a door opening equally to both. Then there should be a separate lounge where women could read over the material they’ve been offered, consider the lab results and sonograms, and then they should have a week or so to consider what they want to do. Or, if they are afraid of pressure from boyfriends or parents, a temporary refuge where they can stay while they think about it.
I’ve already posted, in response to Dan on another article, what I mean by unformed potential. There is a huge qualitative difference between
a)no limbs, neurons or specialized cells, and
b)specialized cells exist, but have not grown into physical organs, and
c) organs all formed, but have some growth to do over time.
I don’t consider those distinctions to be pounding the table. Ultimately, I see a distinction between the mindless numbers game of biology and the self-awareness of a unique human organism. That’s as far as where the law should enter in. On the other hand, if a woman feels that abortion would be a violation of herself, which is I think what many of the regrets you speak of stem from, by all means she should carry the pregnancy to term.
“There is a huge qualitative difference between
a)no limbs, neurons or specialized cells, and
b)specialized cells exist, but have not grown into physical organs, and
c) organs all formed, but have some growth to do over time.”
None of these things establishes a difference in the *kind* of entity that exists over time. Each of a), b) and c) above are merely *stages* along the gapless continuum of development of an individual human being.
In order to be self-consistent, you would have to admit that you do not believe that human beings are valuable by virtue of the kind of entity that they are, and that you require an additional attribute.
Your use of the word “kind” indeed is not significant to me. Stages make a difference. Every stage does not make the same difference.
Consider the value of medical treatment for common infectious diseases. The most important reason for such treatment is that a unique, individual life, infinitely precious and irreplaceable, is threatened with death. The survival of the species is not the point at all. The individual life is. A person who is aware of themselves, their aspirations, of other people who depend upon them. Even if I were implacably fixated on the urgency of immediate population control, at the moment when that individual human being is facing death, and could be saved by a transfusion, by an antibiotic, by surgery, the point is that individual’s survival, for themselves, and for those who love and need and depend upon them. It is of course true that if nobody loves, needs, or depends upon them, I would treat them for themselves alone. But later for the statistical implications.
Why don’t I see that in a zygote, a blastocyst, an embryo? Because those stages do not have the same physical, cognitive, self-awareness. I can still think of them the same way I think of trillions of cells in millions of combinations, the same way I think of 500 million sperm cells dying so that 50 can reach the ovum, and all but one of those die also. When the potential of genetic code, or of a few types of thelial cells, differentiates into specialized organs with neuronic pathways, then I know that the potential has been realized, and a complex, qualitatively different being has emerged, which now only needs nurturing and growth, but behold, the new has come, the old has passed away.
OK, so “physical, cognitive, self-awareness” is the additional attribute that matters to you. Actually, it seems to be the *immediately exercisable* capacity for “physical, cognitive, self-awareness” that really matters to you. But you leave open the question of how immediate is has to be and to what degree it has to be developed. This capacity continues to develop well after birth, and the degree to which it ultimately develops differs from one individual to the next.
A human being at a later stage of his or her natural development, who has developed the immediately exercisable capacity for self-awarness, has possessed this capacity all along, from the moment he or she came into existence, although it was not always immediately exercisable.
“…which now only needs nurturing and growth…”
You could say exactly the same thing about an embryonic human being!
No Dan, an embryonic human being has yet to transform itself by the growth of any specialized organs. or any neural system at all. Further, if it found itself outside the womb, for any reason, it would quickly shrivel up and die.
If a hydra started budding, would it be murder for the adult to cut off the bud?
No Dan, an embryonic human being has yet to transform itself by the growth of any specialized organs. or any neural system at all.
Where do you get that idea? The brain has already been forming and has become highly complex by as early as the third week past fertilization, Siarlys:
“By 3 weeks the brain is dividing into 3 primary sections called the forebrain, midbrain, and hindbrain.
Development of the respiratory and digestive systems is also underway. ”
Watch video:
http://www.ehd.org/movies.php?mov_id=216
“Between 4 and 5 weeks, the brain continues its rapid growth and divides into 5 distinct sections.
The head comprises about 1/3 of the embryo’s total size.
The cerebral hemispheres appear, gradually becoming the largest parts of the brain.
Functions eventually controlled by the cerebral hemispheres include thought, learning, memory, speech, vision, hearing, voluntary movement, and problem-solving.”
Video:
http://www.ehd.org/movies.php?mov_id=24
“By 6 weeks the cerebral hemispheres are growing disproportionately faster than other sections of the brain.
The embryo begins to make spontaneous and reflexive movements. Such movement is necessary to promote normal neuromuscular development. ”
Video:
http://www.ehd.org/movies.php?mov_id=28
As for your claim that they have no growth of specialized organs, what do you call the eyes? The ears? The digestive system? The heart?
At 6 weeks, 6 days, the external ear is beginning to take shape.
Watch video:
http://www.ehd.org/movies.php?mov_id=219
“Note the massive liver filling the abdomen adjacent to the beating heart.
The permanent kidneys appear by 5 weeks. ”
Video:
http://www.ehd.org/movies.php?mov_id=25
” By 7 1/2 weeks, the pigmented retina of the eye is easily seen and the eyelids are beginning a period of rapid growth. ”
Video:
http://www.ehd.org/movies.php?mov_id=40
“The fetus can also grasp an object, move the head forward and back, open and close the jaw, move the tongue, sigh, and stretch.
Nerve receptors in the face, the palms of the hands, and the soles of the feet can sense light touch.
“In response to a light touch on the sole of the foot,” the fetus will bend the hip and knee and may curl the toes. ”
http://www.ehd.org/movies.php?mov_id=53
Siarlys: the issue of when a brain develops is irrelevant to my argument (sorry Bethany!). The moral value of a human being does not depend on the immediate existence of a brain, nor does it depend on the immediately exercisable capacity for conciousness.
I think you *could* (maybe) argue self-consistently that you value human beings based on such things, but then you would have to admit that you value some human beings more than others.
“Further, if it found itself outside the womb, for any reason, it would quickly shrivel up and die.”
Not so fast… see my comment above about artificial wombs:
https://gerardnadal.com/2010/01/28/pro-life-academy-biology-cells-v/#comment-1218
No don’t apologize Dan! 🙂 I absolutely agree with you- it IS irrelevant to the humanity of the unborn!
I know that Siarlys’ premise is that humanity is based on brain activity, which couldn’t be further from the truth.
Siarlys keeps making these false claims, though, and I felt the need to show him that he was wrong in his statements about embryonic development.
I really appreciate your posts, Dan! 🙂
Gentle Scholars,
In arguing this point of when a human organism becomes human, these threads are beginning to look like a dog chasing its tail. Human identity at the orgaanismal level has been established BY EMBRYOLOGY to be at the very first stage, the zygotic stage.
If any pro-choice proponent wishes to engage in self-delusion, they are free to. Science has spoken. Period. Don’t get sucked in. Just point to the scientific data.
Force the real issue, which is the DENIAL of what embryology has pronounced. Then force the pro-choicers to explain why they know better than science.
A new human organism exists from the moment of fertilization. The only question is why one would deny a human being full moral status.
If they state that it’s because the organism is not yet human, stand solidly on the list of medical text quotes that I’ve furnished here and that are linked at the end of this post.
It’s rare that I come out of my cave and suggest HOW to argue a point, but I’m getting a little weary of watching pro-choicers dismiss the science, suggesting that they know better than the most qualified in the world when it comes to the human organismal identity of the embryo.
They do not know better than us in science. They are not more qualified than us. So here is where we must force their hand-to show how utterly arbitrary, convenient and capricious their timelines are.
The one thing they are not is scientific.
God Bless
Actually, Dr. Nadal, I believe you are reading into the scientific texts a meaning that was not even on the minds of those who wrote it — rather like proponents of same-sex marriage reading into marriage statutes, or judicial precedents, meanings that were not even on the table, from ages when not one person who practiced homosexuality had even thought of what they did as comparable to marriage.
You have the most sincere of motives, but when you headline your purpose as “Science in the Service of the Pro-Life Movement” you express your willingness to array both bare facts and complex analysis in a manner that will serve the movement, rather than conform the movement to whatever science may indicate. You have a goal and a purpose, therefore, your knowledge of science must be presented in a manner that serves your purpose.
But I will freely state that the relevant question for me is not genetic identity, but physical and self-conscious realization of the potential contained in the 23 chromosome pairs. When the arms are there, not implicit, when the neurons are aware, not the predictable future result of a series of unconsummated RNA transactions, then of course we must protect the new life that has now actually formed.
SJ,
I’m not reading anything into the scientific texts. Read this entire blog carefully.
Science has pronounced that at the moment of fertilization that a new human organism exists.
Is that clear enough?
A new human organism exists at fertilization.
Period.
From that I have then engaged the physical, metaphysical, ethical, theological and legal dimensions.
What is the ethical/ moral/legal status of this new human animal, which Embryology tells us is a separate and distinct human animal/organism?
How is status to be determined?
This is the point at which we are forced to confront the idea that an organism’s status is determined by the KIND of thing it is: Dog v. Human. Dogs do not get human rights. Humans get human rights.
AGAIN, embryology tells us both what is present at fertilization (a new organism, separate and distinct from its parents) as well as WHAT KIND of organism it is: HUMAN.
Human organisms are entitled to human rights based upon the KIND of organism they are: HUMAN.
This is where you come in and try to redefine what KIND of an organism s present at fertilization and further restrict rights based upon arbitrarily determined criteria regarding the functionality and developmental stage of the organism.
So, nice attempt to portray me as a sloppy academic. Better luck next time.
You’re not sloppy, just biased. We all have our biases. Pronouncement is a subjective choice, rather than the inevitable outcome of rigorous study. The language you use is a characterization. Its not like saying “water is two hydrogen atoms and one of oxygen. It’s not like figuring out Avogadro’s number. My fingernails are human. So is ever hair on my arm. The zygote is human in the same sense, but it is not yet a human being. That’s my position. We don’t differ on the data, just on the moral implications of its future potential. Your insistence that “science has pronounced” is self-serving, of a conviction you held a priori any scientific consideration. It is a conviction you have every right to hold. But alternatives are not ruled out by any objective science.
Oh, for crying out loud, Siarlys, a human zygote is *not* the same thing as the hair on your arm! A human zygote is neither functionally nor genetically *part* of any other organism. You need to understand the scientific question of what an embryo is before you can begin to address meaningfully the philosophical question of what moral respect, if any, a human embryo deserves.
SJ,
Straight question. Do you accept or reject the consensus in Embryology that a new human organism exists at fertilization? Yes or No?
SJ, Gerard and Dan,
Gerard seems to be talking about a ‘human organism’ while Siarlys is talking about a ‘human being.’