![]() And the control mechanisms and principles that govern the regular development of the bones and muscles of legs and arms also are very similar in both. Not only are the eyes and ears similar in their development, but so are the early stages of the brain, the digestive system, the skin, and the kidneys, to name only a few. There are many other similarities in the development of people and pigs as well, both in structure and in developmental control mechanisms. In pigs the story goes a little different, because there the legs grow along the spine, too, but their corkscrew tail does stick out beyond the end of the body, as it was designed to do. And the tail that is sometimes depicted in textbooks is not the end of the vertebral column, as it would have to be in order to be homologous with the pig's tail, but only a fleshy one, which can be removed surgically, without involving the vertebral column. After all, there has to be some kind of end to the vertebral column.įinally, what about the occasional infant that is "born with a sizable and unmistakable tail?" This is not any different from occasional children being born with other abnormalities, and indicates only that in the development of this individual something went wrong at a particular time in that specific location. And the muscles which attach to that part of the spine have definite and useful functions. In actual fact, the coccyx is just an adult structure which is necessary, and without which we would have difficulty functioning normally. But it symbolizes that only to those who have faith in the story of evolution. Secondly, what about being left "with only our symbolic coccyx?" The question is, then, "Of what is it symbolic?" The intention is obviously to suggest that it symbolizes our animal ancestry. In adults there is still that tail bone, but the end of the spine is then surrounded with hip and leg structures, such as bones, muscles, nerves, and blood vessels, all of which are necessary for normal functioning. And in so doing they grow around that early tail-like structure, which is really the end of the spine, so that definitive relationships can be established. It doesn't take long, however, before these leg buds elongate, develop bones and muscles, and start looking like regular tiny baby legs. At this time the legs are only just beginning to form as little paddle-shaped buds. And it is so noticeable because there are no legs yet to obscure its presence. To be more specific, that tail consists of the end of the vertebral column. That there is a tail is a well-established fact. The authors thus indicate that they see a problem for us.Ī closer look shows us, first of all, that they are correct in saying that we have a tail at that stage, and that it is as well developed as that of a pig of that stage (not of an adult pig, of course). Occasionally, to the discomfiture of anti-evolutionists, this regression fails to occur, and a human infant is born with a sizable and unmistakable tail. The tail in our own later development normally undergoes regressive changes that leave us with only our symbolic coccyx. 5 weeks – AM) the human embryo has every bit as well developed a tail as a pig. It is interesting that at this state (ca. In a classic example in an older textbook of Embryology, the authors, discussing the development of the lower end of the spine, say And it does not indicate that we evolved. But we need not at all be uncomfortable about this. Some people think that this should make us Christians uncomfortable, because they think that this would indicate that we developed from animals through evolution. and to other animals at a comparable stage. At this stage the end of the backbone projects from the body, very similar to that of a pig of 4 mm. long, the backbone is taking shape, including some tailbone features. When the embryo is four weeks old and about 4 mm. From implantation up to the tenth week this new individual, who is developing in the womb, is called an embryo. At this time a vigorous growth period begins. Then, on about the ninth day after fertilization, it is implanted into the lining of the uterus. So let's look at what the situation is at our beginning stages.Īfter the human ovum is fertilized it takes about four days to travel through the uterine tube and to arrive in the uterus. ![]() But only when we are very small, long before we are born. Did you ever hear of people having a tail? It may seem strange, but we do. ![]()
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