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<p> To understand concept, cause and consequence of evolution is very important to research on a number of biology field. Since the time of Darwin, who suggest the first model of evolution, there are many controversies around evolution including conflict between religions and evolutionists, and different views to explain the way the evolution occurs. In this short essay, we will focus about Darwin's first model through critical view with well-known therories and evidences and briefly evaluate about his theory with basic biological lens including development, growth, reproduction and inheritance of life.Abstract</p>
<p> Darwinism is a theory of biological evolution developed by English naturalist Charles Darwin, stating that all species of organisms arise and develop through the natural selection of small, inhereted variations that increase the individual's ability to compete, survive and reproduce. Pangenesis, which is a theory of heredity hypothesized by Darwin, was supporting Darwinism as it explained heredity of variations. I found that Gregor Mendel's experiments and other evidences attacked Darwinism by refuting pangenesis. Hence, Darwinism supported by pangenesis is not perfect to explain the biological evolution.</p> <p> </p> <p>Introduction</p> <p> Since 1832, when Charles Darwin arrived at Galapagos islands where various traits and species exists, the concept of evolution has been considered as one of the most powerful tool to explain the variety and origin of life. But, as crucial evidences and theories such as Mendel's law of inheritance emerged, the theory of evolution has been changed gradually, which makes the first model obsolete. Through that way, we ard are ignorant about what Darwin's original theory tried to say. Now, in this essay, we want to focus more about Darwin's first model and criticize it on many biological terms.</p> <p> </p>
<p><strong>Darwin's Explanation : Gemmule and Pangenesis</strong></p>
<p><strong>Defects on Pangenesis</strong></p>
<p>1. Pangenesis can not explain Mendel's Cross expriments.</p>
<p> Gregor Mendel's study totally defeated Darwin's mechanism. Mendel proved that heredity has at least one certain discrete unit to express one trait. Unfortunately gemmule couldn't be that unit as it was continuous concept and did not have method to explain law of dominance, segregation and independent assortment..</p>
<p>2. Acquired traits are not inherited.</p>
<p> Lamarckism was very similar to Darwinism in that both were trying to explain that evolution occured within relatively short time. Both are not true because acquired traits are not inherited (but epigenome), which cannot affect phynotypes. </p>
<p>3. Pangenesis can not explain asexual propagation</p>
<p> According to the pangenesis, gemmule should be inhereted by sexual propagation. However, there are many asexual reproductions such as binary fission, budding, and vegetative propagation.</p>
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<p><strong>Reference</strong></p>
<p>https://en.wikipedia.org/wiki/Pangenesis</p>
<p>https://en.wikipedia.org/wiki/Gemmule_(pangenesis)</p>
<p>https://en.wikipedia.org/wiki/On_the_Origin_of_Species</p>
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