MadSci Network: General Biology |
John, Your question is rightfully controversial. There is no objective answer that can be proved or disproved. I will offer my opinion and I will try to stay within the limits of language. I will try not to make categorical statements that cannot be tested. Both of the terms you use, Human and Being, reflect life outside of the uterus. The condition of being human is not just anatomical, it is also related to intellectual and physical attributes. The condition of being a "being" is connotes independence on another for existence. This is why scientists and physicians refer to stages of becoming a being. That is, first there is a fertilized egg, then a blastocyst, then an embryo, then a fetus, and only until the fetus reaches full term and is ejected from the uterus does it become a baby. As the baby develops in a nurturing and intellectually stimulating environment, it learns human traits and becomes a human being, in my opinion. Statistically, 60% of all joinings of sperm and egg to form a fertilized egg fail to become embryos, fetuses or babies. This is because the process of development requires that each stage occurs perfectly or biological mechanisms monitoring cell growth and disposition will trigger spontaneous death of critical cells and the embryo and is either ejected or absorbed inside the uterus. A non-viable embryo or fetus ends its existence before it reaches stages where I would call it a human being. In older human embryology books the phrase, "ontogeny recapitulates phylogeny" was used. It was thought, incorrectly, that from fertilization onward the developing forms resembled single cell organisms like amoebae, multicellular organisms like hydra, and complex primitive vertebrates like amphioxis, tadpoles and then mammals. This is because of the shape changes and the lack of resemblance of the products of conception to anything apparently human. However, by 12 weeks gestation a fetus, who by now has become like a parasite living on filtrates of the mothers blood that it obtains via a placenta, looks like a small model of what it will later become. It is totally dependent on the nutrition and oxygen it obtains from the mother and will die shortly after being disconnected to the mother via the placenta or if the mother consumes something that is toxic to it even if it may not be seriously toxic to her. Even while the fetus has a head, shoulders, arms, hands with finger, trunk, legs and feet with toes, it is not yet a human being to me. However, by the this time the mother and father of this fetus will have built up strong anticipations of what this fetus will become when it is born. Many fetuses are lost due to spontaneous abortion, called still birth, and the expectations the mother and father hold cause them to grieve for what might have been. I believe most people would think a fetus at this stage is a human being because of the emotional attachment. But, as the fetus is so dependent on being attached inside to the mother and because no one has ever described intellectual attributes of humanness in fetuses, I am not ready to say it is a human being, regardless that many grieve over the loss of a fetus. Fertilized eggs, blastocyts, and embryos are lost without anyone noticing although couples suffering from the condition of infertility probably would also grieve over the loss of an embryo. The online dictionary Wikepedia provides some useful information that can help expand on what I have said about what is human and when in the cycle of life a fertilized egg, blastocyst, embryo, or fetus may become an human being. http://en.wikipedia.org/wiki/Hum an In earlier times, like during the colonization of North America, fetuses that reached full term and were born as babies often did not survive to reach 1 year of age. In some cultures newborns would never be placed on the ground because it was believed that this would hasten there demise. In these cultures, the family would hold a ceremony at 6 or 12 months to attest to the viability of this child and to begin to allow it to move around on the ground. This practice suggests to me that families may have postponed regarding the new born as human until it succeeded in postnatal survival. Even today, with better living conditions and better health care, a significant number of newborn babies die before they reach their first birthday. So, now it comes down to opinion. Do I regard a baby as a human being or not. I believe I do regard a baby, capable of living outside the womb, as a human being. It is clear that babies initiate and maintain a constant nonverbal and audible connection with its parents and caregivers. It learns and applies what it knows to improve its conditions and survival so, yes. I believe babies are human beings. However, I do not believe fertilized eggs, blastocysts, embryos and fetuses (of age where survival outside the womb is not possible) are human beings. Many people will disagree with this determination. I have listed my criteria and reasons for the belief that I stated. I have tried to not repeat what others have told me or required me to say. I have not taken a purely emotional position based on expectations and aspirations; and, I have tried to provide expamples to support the opinion I stated. I believe, bodies of philosophers, physicians and ethicists such as the National Bioethics Advisory Commission, have arrived at similar positions but I am not merely adopting their position. http://www.bioethics.gov/reports/past_commissions/nbac_cloning.pdf Fundamentalist Christian organizations take the position that fertilization begins the life of a human being. As sperm are living, and the egg is living, life was present before fertilization. http://www.mtio.com/artic les/bissar61.htm Fertilization merely allows this life to have a complete set of 46 chromosomes, one set of 23 from the father and another set of 23 from the mother. Taking an adult cell and tricking it into dividing in vitro would be a similar form of life but it would not become an embryo and it would certainly not become a human being. An adult cell taken from a woman with cervical cancer at Johns Hopkins early in the 20th century still lives on as the "HeLa cell line." Because this cell line has outlived the persons who isolated it, and continues to survive in research laboratories all over the world, would we say this cell line is a human being that has become immortal; of course not, But, for all intents and purposes it is, but it isn't a human being. My opinion is also not a legal decision, as judges may decide that a fertilized egg is a human being for purposes of prosecution in a trial as is expressed in this news report. http://www.npr.org/templates/story/story.php? storyId=4492781 I am not taking a legal position but proved this reference for your consideration. http://learn.genetics.utah.edu/units/cloning/clonezone/timeline_zone .swf So, John, it is up to you to draw your own opinion. I hope the information I provided helps.
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