Embryonic RecapitulationThe idea that human embryonic development recapitulates the evolutionary pathway has long been disproved but is still taught in some textbooks.The idea that human fetuses have gill slits is a part of what was known as the Biogenetic Law. "The idea that the embryo of a complex animal goes through stages resembling the embryos of its ancestors is called the Biogenetic Law." This "Law", also known as recapitulation theory, (i.e., "ontogeny recapitulates phylogeny") was formulated in 1866 by Dr. Ernst Haeckel, an early scientific convert to Darwinism. In 1874 another German professor, Wilhelm His, showed that Haeckel had deliberately altered earlier sketches of human and dog embryos to support the Biogenetic Law. Professor His was ignored by evolutionists in spite of the "blatant fraud" and the exacting detail in which he was able to show how the fraud had been generated. Taylor comments: "His, whose work still stands as the foundation of our knowledge of embryological development, was not the first to point out the deficiencies of Haeckel's work, nor indeed was he the last, yet Haeckel's fraudulent drawings have continued to the present day to be reproduced throughout the biological literature." This dishonesty was admitted in the Introduction to the Centennial Edition of Darwin's Origin of the Species (1956): "When the 'convergence' of embryos was not entirely satisfactory, Haeckel altered the illustrations of them to fit his theory. The 'biogenetic law' as proof of evolution is valueless." Nonetheless, the propaganda value of "gill slits" is strong, and it lives on. In a debate with creationist Dr. Duane Gish, anti-creationist Dr. Ashley Montagu said, in response to a reference to this fraud: "The theory of recapitulation was destroyed in 1921 by Professor Walter Garstang in a famous paper, since when no reputable biologist has ever used the theory of recapitulation, created by a Nazi-like preacher [sic] named Haeckel." quoted from Eric J. Blievernicht Wrong From the Start: Based on the book "Icons of Evolution" by Jonathan Wells (Oct 2000). Among the most blatantly false icons are the embryo drawings that attracted Wells' attention. The pictures were drawn in the 1800s by German zoologist Ernst Haeckel (pronounced heckle), an enthusiastic supporter of Darwin's theory of evolution. Haeckel proposed that the development of an organism's embryo replays the evolutionary history of that organism's species. He believed that as new organs or structures evolved, these features were tacked onto the end of an organism's embryonic development. As a result, we can virtually see the organism's evolutionary history in the embryo's development. At the beginning of its development, the embryo looks like its earliest ancestor. But as it develops and more recent features appear, it resembles later ancestors--until it finally reaches the point where it resembles its own species. Haeckel called this the biogenetic law. On the basis of this law, he reasoned that the embryos of various organisms should look virtually identical early in development, but grow increasingly different over time--reflecting their evolutionary descent from a common ancestor. And when he made drawings of the embryos of several backboned animals, this is exactly what his drawings showed. Unfortunately, Haeckel had more enthusiasm for his theory than for reality, and faked many of his drawings. "In some cases," Wells says, "Haeckel used the same woodcut to print embryos that were supposedly from different classes [of animals]. In others, he doctored his drawings to make the embryos look more alike than they really were. His contemporaries repeatedly criticized him for these misrepresentations, and charges of fraud abounded in his lifetime." In addition to doctoring his drawings, Haeckel also misrepresented the embryos' development. The stage of development that Haeckel called the "first" stage actually occurs about midway through the embryos' development. And although the embryos at this midway stage look faintly similar (if you squint hard and step back a bit), embryos at the earlier stages differ greatly. Thus, instead of starting out virtually identical and then diverging, the embryos differ from the very beginning. About midway through development they converge to a vague similarity. Then they diverge again to their final forms. Wells points out that biologists have known this for over a century. In 1894, for example, embryologist Adam Sedgwick rejected the idea that embryos start out similar and diverge over time, stating that this view is "not in accordance with the facts of development." Sedgwick noted that he could distinguish between a chicken and a duck as early as the second day of development. "Every embryologist knows that [early differences] exist and could bring forward innumerable instances of them," he said. "I need only say with regard to them that a species is distinct and distinguishable from its allies from the very earliest stages all through development" (emphasis in the original). Sedgwick's observations are confirmed by modern embryology. In spite of this, Wells found that Haeckel's drawings are almost universally touted in biology textbooks as powerful evidence for evolution. This is even the case in some advanced college texts written by eminent scientists. Haeckel's drawings appear, for example, in the latest edition of Molecular Biology of the Cell, written by National Academy of Sciences president and distinguished cell biologist Bruce Alberts and his colleagues. The text states that "early developmental stages of animals whose adult forms appear radically different are often surprisingly similar," and that Darwinian evolution explains why "embryos of different species so often resemble each other in their early stages and, as they develop, seem sometimes to replay the steps of evolution." Excerpt from Crumbling Icons by Mark Hartwig, Boundless, December 7, 2000 , Boundless Books:
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