Lamarck and Darwin: Comparative Analysis of Evolutionary Theories

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Jean-Baptiste Lamarck, a French naturalist who lived from 1744 to 1829, set forth in his Philosophie Zoologique the idea that an organism’s form and inheritance are influenced by its circumstances (Philosophie Zoologique 1809). Lamarck’s theory of evolution, also known as Lamarckism, proposed [Lamarck’s theory of evolution, also known as Lamarckism, was based on the principle that an organism could pass acquired characteristics onto its offspring. (Futuyama 2013; Campbell and Reece 2005; Stansfield 2011). Lamarckism never gained popularity, in part because of criticism it received from other scientists and also because many French ideas were discredited after the French Revolution (Futuyma, 2013). Mendel’s laws of genetics and Darwin’s theory of natural selection eventually replaced Lamarck’s (Balter 2000).

Charles Darwin, a British naturalist who lived from 1809 to 1882, proposed the theory of natural selection in his book, The Origin of Species. Natural selection occurs when fitness of a gene, organism, population, or species increases due to a …show more content…

Chromatin, the genetic material of which the chromosomes of eukaryotes are composed, is made of DNA, RNA, histones and non-histone proteins. Families of enzymes act as catalysts for the addition and removal of ligands of chromatin, and some even change the structural unit. These enzymes are sensitive to the presence of environmental and metabolic chemicals and activation of these enzymes can alter gene expression. Sometimes, the change in gene expression continues after the original chemical is no longer present. This gene expression can be passed on, through mitosis, to the next generation of cells. If these changes occur in germ cells, then these environmentally induced changes could be heritable. So it follows that if this new epigenetic change is heritable and affects the phenotype in a way that increases fitness, could directly influence evolution (Turner

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