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Over at Pharyngula, Professor P.Z. Myers has been ridiculing Senator Marco Rubio for declaring, “The science is settled, it’s not even a consensus, it is a unanimity, that human life beings at conception” – a claim he repeated at the GOP debate on August 6. Unfortunately for Myers, Senator Rubio is dead right: embryologists agree that an individual human life begins at conception.
Here’s how Professor Myers attempted to dispose of Senator Rubio’s claim in a 2014 post:
Let’s take that phrase “human life begins at conception” apart.
What do you mean by “life begins”? Was there some step between your parents and you where there was a dead cell? Life is continuous — there hasn’t been a transition from non-life to life for about 4 billion years. So, yes, I’d agree that the zygote is a living cell, but so were the sperm and egg that fused to generate it, and so were the blast cells that were precursors to it, and so were the zygotes that developed into your parents. We can trace that life all the way back to early progenotes with limited autonomy drifting in Archean seas, to self-perpetuating chemical reactions occurring in porous rocks in the deep ocean rifts. It’s all been alive, so this is a distinction without meaning.
What about “human”? It’s a human zygote, we’d all agree; but it’s also human sperm and human ovum. You can pluck a hair from my head and determine with a few tests that it’s a human hair; you can take a blood sample from me and check a few antigens and determine that it is human blood; you can similarly swab a bit of saliva or earwax or tears from me, and analyze its biochemistry and find that it is specifically human spit or earwax or tears. That we can tag something with the adjective “human” does not in any way imply that my earwax deserves all the protections and privileges of a full human being. “Human zygote” imposes as much ethical obligation on me as “human spit”.
And don’t even try to pull that BS about a unique, novel genetic individual being created at conception. One of the key properties of meiosis is a genetic reshuffling of alleles by random assortment of the parental chromosomes and recombination by crossing over — every sperm and egg is genetically unique as well, and we spew those profligately with no remorse. Conception just adds another level of semi-random rearrangement of a random assortment of genes that were made during oogenesis and spermatogenesis. (“Marco Rubio is already Gish-Galloping,” 17 May 2014.)
In an article in Slate titled, Marco Rubio Wants You to Know that a Fertilized Human Egg Cannot Become a Cat (or a Donkey) (August 11, 2015), Amanda Marcotte cited P.Z. Myers’ 2014 post when she triumphantly declared:
Actual biologists, for what it’s worth, argue that life is continuous and that a fertilized egg is no more or less alive than a sperm or an unfertilized egg.
Ms. Marcotte added:
Human sperm cells, much like fertilized eggs, have human DNA. If a sperm cell is allowed to complete its development process instead of dying sadly with a million of his brothers inside a dirty gym sock, it will also, coupled with an egg, develop into a human being.
Clearly, the only solution is to ban masturbation.
The juvenile gutter humor of pro-choice advocates never ceases to amaze me.
In a follow-up post titled, Christians can get awfully reductionist when it suits them (August 11, 2015), Professor Myers gleefully cited Ms. Marcotte’s article in Slate and poked fun at Senator Rubio’s “stupid gotcha” in the GOP debate:
This seems to be the core pseudo-scientific premise of the anti-choicers, and it rests on a fundamental flaw in their reasoning. Yes, it’s true that a human zygote is alive and cannot become a cat or a donkey, but “human” here is being used in the broadest possible sense. We do not offer full rights and protections to everything that is “human”, or bleeding, spitting, and masturbation and menstruation would be illegal. Those acts also destroy living, human cells that cannot become donkey or cat cells.
As it happens, I refuted Myers’s scientific fallacious arguments three years before he posted them, in my online e-book, Embryo and Einstein: Why They’re Equal. What follows is an excerpt from my e-book.
When does a new human individual begin?
One often encounters the pro-choice argument that a human ovum and a sperm cell are both human and alive, so it is wrong to claim that human life begins at conception. Equally common is the tired objection that human life is an unbroken continuum, with no “magic moment” at which a new human life appears.
Both of these objections are flawed, insofar as they overlook the vital distinction between “human life” and “the life of a new human being.” This distinction is carefully explicated by Dr. Dianne N. Irving, M.A., Ph.D., a former career-appointed bench research biologist/biochemist, NCI, NIH; philosopher and medical ethicist, in her online article, When Do Human Beings Begin? “Scientific” Myths and Scientific Facts:
[T]here is a radical difference, scientifically, between parts of a human being that only possess “human life” and a human embryo or human fetus that is an actual “human being.” Abortion is the destruction of a human being. Destroying a human sperm or a human oocyte would not constitute abortion, since neither are human beings. The issue is not when does human life begin, but rather when does the life of every human being begin. A human kidney or liver, a human skin cell, a sperm or an oocyte all possess human life, but they are not human beings — they are only parts of a human being. If a single sperm or a single oocyte were implanted into a woman’s uterus, they would not grow; they would simply disintegrate.
Indeed, there is a very high degree of agreement among embryologists that fertilization normally marks the beginning of the human being as an individual organism, and that the sperm and oocyte (unfertilized egg, in popular parlance) which exist prior to that point are human cells, but not human organisms. The following selection of statements from embryology textbooks should suffice to refute the pro-choice canard that “life is a smooth, unbroken continuum”:
“Human development begins at fertilization, the process during which a male gamete or sperm … unites with a female gamete or oocyte … to form a single cell [embryo]. This highly specialized, totipotent cell marks the beginning of each of us as a unique individual. (p. 18) … The usual site of fertilization is the ampulla of the uterine tube [fallopian tube], its longest and widest part. If the oocyte is not fertilized here, it slowly passes along the tube to the uterus, where it degenerates and is resorbed. Although fertilization may occur in other parts of the tube, it does not occur in the uterus. … The embryo’s chromosomes sex is determined at fertilization by the kind of sperm (X or Y) that fertilizes the ovum; hence it is the father rather than the mother whose gamete determines the sex of the embryo.” [Keith Moore and T.V.N. Persaud, The Developing Human: Clinically Oriented Embryology (6th ed. only) (Philadelphia: W.B. Saunders Company, 1998), p. 37].
“Human pregnancy begins with the fusion of an egg and a sperm. (p. 3); … finally, the fertilized egg, now properly called an embryo, must make its way into the uterus (p. 3); … The sex of the future embryo is determined by the chromosomal complement of the spermatozoon … Through the mingling of maternal and paternal chromosomes, the [embryo] is a genetically unique product of chromosomal reassortment …” [Bruce M. Carlson, Human Embryology and Developmental Biology (St. Louis, MO: Mosby, 1994 ), p. 31; ibid, Carlson 1999, pp., 2, 23, 27, 32].
“In this text, we begin our description of the developing human with the formation and differentiation of the male and female sex cells or gametes, which will unite at fertilization to initiate the embryonic development of a new individual. … Fertilization takes place in the oviduct [not the uterus]… resulting in the formation of an [embryo] containing a single diploid nucleus. Embryonic development is considered to begin at this point…” (p. 1). [William J. Larsen, Human Embryology (New York: Churchill Livingstone, 1997), p. 17].
O’Rahilly 2001 – Table 8-1
“Principal Features of Developmental States of the early human embryo: Stage 1 – Includes penetrated oocyte, ootid, and zygote. Thus accordingly, the penetrated oocyte and the ootid (before syngamy) are characterized as an already existing human embryo at Stage 1 of development.” [Ronan O’Rahilly and Fabiola Muller, Human Embryology & Teratology (New York: Wiley-Liss, 2001), p. 89]. (Emphases mine – VJT.)
The French geneticist Jerome L. LeJeune has stated:
“To accept the fact that after fertilization has taken place a new human has come into being is no longer a matter of taste or opinion. The human nature of the human being from conception to old age is not a metaphysical contention, it is plain experimental evidence.” [The Human Life Bill: Hearings on S. 158 Before the Subcommittee on Separation of Powers of the Senate Judiciary Committee, 97th Congress, 1st Session (1981). See Norman L. Geisler, Christian Ethics: Options and Issues (Grand Rapids, MI: Baker Books, 1989), p. 149 also Francis J. Beckwith, Politically Correct Death: Answering the Arguments for Abortion Rights (Grand Rapids, MI: Baker Books, 1993), p. 42.] (Emphases mine – VJT.)
Dr. Hymie Gordon, professor of medical genetics and Mayo Clinic physician stated:
“I think we can now also say that the question of the beginning of life – when life begins – is no longer a question for theological or philosophical dispute. It is an established scientific fact. Theologians and philosophers may go on to debate the meaning of life or purpose of life, but it is an established fact that all life, including human life, begins at the moment of conception.” [The Human Life Bill – S. 158, Report 9, see Francis J. Beckwith, Politically Correct Death: Answering the Arguments for Abortion Rights (Grand Rapids, MI: Baker Books, 1993), p. 42.] (Emphases mine – VJT.)
Dr. Micheline Matthew-Roth, a principal research associate at Harvard Medical School’s Department of Medicine states:
“It is scientifically correct to say that an individual human life begins at conception, when egg and sperm join to form the zygote, and this developing human always is a member of our species in all stages of life.” [The Human Life Bill – S. 158, Report together with Additional and Minority Views to the Committee on the Judiciary, United States Senate, made by its Subcommittee on Separation of Powers, 97th Congress, 1st Session (1981) see Francis J. Beckwith, Politically Correct Death: Answering the Arguments for Abortion Rights (Grand Rapids, MI: Baker Books, 1993), p. 43] (Emphasis mine – VJT.)
What I am arguing here is that the life of a new human being normally begins when the sperm penetrates the ovum (or more accurately, the oocyte). (I say “normally” because the example of human cloning shows that there’s more than one way to make a new human life.) This process take one second to occur, as Professor Maureen Condic explains in her online paper, When Does Human Life Begin? A Scientific Perspective (White Paper Volume 1, Number 1, October 2008, published by The Westchester Institute for Ethics and the Human Person):
The basic events of early development are both reasonably well characterized and entirely uncontested. Following the binding of sperm and egg to each other, the membranes of these two cells fuse, creating in this instant a single hybrid cell: the zygote or one-cell embryo… Cell fusion is a well studied and very rapid event, occurring in less than a second. Because the zygote arises from the fusion of two different cells, it contains all the components of both sperm and egg, and therefore the zygote has a unique molecular composition that is distinct from either gamete.
Subsequent to sperm-egg fusion, events rapidly occur in the zygote that do not normally occur in either sperm or egg. The contents of what was previously the sperm, including its nucleus, enter the cytoplasm of the newly formed zygote. Within minutes of membrane fusion, the zygote initiates changes in its ionic composition that will, over the next 30 minutes, result in chemical modifications of the zona pellucida, an acellular structure surrounding the zygote… These modifications block sperm binding to the cell surface and prevent further intrusion of additional spermatozoa on the unfolding process of development. Thus, the zygote acts immediately and specifically to antagonize the function of the gametes from which it is derived; while the “goal” of both sperm and egg is to find each other and to fuse, the first act of the zygote is immediately to prevent any further binding of sperm to the cell surface. Clearly, then, the prior trajectories of sperm and egg have been abandoned, and a new developmental trajectory—that of the zygote—has taken their place. (p. 3) (Emphases mine – VJT.)
End of excerpt. On this point, I think we can safely say (with apologies to St. Augustine): “Science has spoken; the case is closed.”
When does pregnancy begin?
And what about that put-down article last year by Philip Bump in the Washington Post (May 15, 2014), which attempted to muddy the waters with its assertion that pregnancy begins at implantation, 5 to 9 days after conception? First, even if that were true, it would be utterly irrelevant: the question Senator Rubio was discussing was not when pregnancy begins, but when a new human individual begins: at conception. Second, the American College of Obstetricians and Gynecologists’ decision in the mid-1990s to redefine pregnancy as a process that occurs at implantation was taken for purely political reasons (see footnote 26 of this article by Dr. Dianne N. Irving, cited above). Here’s how other medical textbooks define the onset of pregnancy (emphases mine – VJT):
Human pregnancy begins with the fusion of an egg and a sperm, but a great deal of preparation precedes this event. First both male and female sex cells must pass through a long series of changes (gametogenesis) that converts them genetically and phenotypically into mature gametes, which are capable of participating in the process of fertilization. Next, the gametes must be released from the gonads and make their way to the upper part of the uterine tube, where fertilization normally takes place. Finally, the fertilized egg, now properly called an embryo, must make its way into the uterus, where it sinks into the uterine lining (implantation) to be nourished by the mother.
(Bruce M. Carlson, Human Embryology and Developmental Biology, St. Louis, MO: Mosby, 1999, pp. 2-3.)
Postcoital birth control pills (“morning after pills”) may be prescribed in an emergency (e.g., following sexual abuse). Ovarian hormones (estrogen) taken in large doses within 72 hours after sexual intercourse usually prevent implantation of the blastocyst, probably by altering tubal motility, interfering with corpus luteum function, or causing abnormal changes in the endometrium. These hormones prevent implantation, not fertilization. Consequently, they should not be called contraceptive pills. Conception occurs but the blastocyst does not implant. It would be more appropriate to call them “contraimplantation pills”. Because the term “abortion” refers to a premature stoppage of a pregnancy, the term “abortion” could be applied to such an early termination of pregnancy.
(Keith L. Moore and T.V.N. Persaud, The Developing Human: Clinically Oriented Embryology, 6th ed., Philadelphia: W.B. Saunders Company, 1998, p. 532.)
The position of the American College of Obstetrics and Gynecology, that pregnancy begins at implantation, is actually a minority position, according to a recent Reuters article titled, When does pregnancy begin? Doctors disagree by Kerry Grens (November 17, 2011):
Most of the polled obstetrician-gynecologists believe pregnancy begins when the sperm fertilizes the egg. But a minority say it doesn’t begin until a week later when the fertilized egg implants in the uterus — the definition given by the American College of Obstetrics and Gynecology (ACOG)…
For the survey, published in the American Journal of Obstetrics and Gynecology, Curlin and his colleagues sent questionnaires to more than 1,000 ob-gyns. The questions asked whether pregnancy begins at conception, at implantation, or if the doctor was unsure.
Most of the doctors, 57 out of every 100, said that pregnancy begins at conception, while 28 out of every 100 said it begins at implantation. The rest were unsure.
Political football, anyone?
Conclusion
So there you have it. Senator Rubio was right after all about the beginning of a new human individual taking place at conception. I wonder if Professor Myers will have the courage to apologize to senator Rubio, in his next post. Incidentally, does anyone remember Myers’ self-righteous post, Remember, you are mortal (October 2, 2014), in which he gave astronomer Neil de Grasse Tyson a little lecture on how to apologize properly?
Finally, readers who object to the notion that an embryo is a person with a right to life are welcome to peruse Part B of my e-book, Embryo and Einstein: Why They’re Equal in which I respond to no less than 18 objections, including the utilitarian objection that only sentient beings are persons with a right to life.