Some argued that if the inheritance of acquired characteristics did not occur

Some argued that if the inheritance of acquired

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Some argued that if the inheritance of acquired characteristics did not occur, then one could not hope for permanent improvement through the conscious exertions of individuals, groups and nations. Herbert Spencer wrote about Weismann’s views and his own in 1887: “I will add only that, considering the width and depth of the effects which acceptance of one or other of these hypotheses must have on our views of Life, Mind, Morals, and Politics, the question - Which of them is true? demands, beyond all other questions whatever, the attention of scientific men.”
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Altruism? Darwin also suspected that natural selection alone could not account for morality and altruism and included the inheritance of habit to explain them. Where did the benevolence of parents and human bravery come from and how could they be perpetuated ? How could natural selection operate on traits which would be for the good of the group but which would have an adverse effect on the individual who carried the trait?
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Altruism Darwin thought that altruistic traits would have evolved in humans through two mechanisms: the inheritance of acquired characteristics and by group selection. The evolutionary mechanism underlying altruistic traits remains the subject of controversy among evolutionists today
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Neo-Lamarckians argued that the struggle for existence played the role of the gardener pruning the tree of life. It no more made the twigs than did the gardener. It would explain the survival of the fittest but not the arrival of the fittest.
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Orthogenesis Orthogenesis was often closely associated with neo- Lamarckism. It was popularized by German zoologist Theodor Eimer in his book, Organic Evolution (translated into English in 1890). He used the term to describe the regular trends described by paleontologists who argued, for example, that the evolution of the modern horse had proceeded in a regular single direction that was difficult to explain by random variation.
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Orthogenesis Such trends would often be non-adaptive, and in some cases orthogenesis could lead the species to extinction. Irish Elk whose relatively recent extinction was thought to be due to its antlers becoming too large. While the antlers may have been useful at first, orthogenesists argued, the trend toward large antlers acquired a momentum of its own, and went too far. They were wiped out by the weight of their ninety- pound antlers 8000 ya. (Perhaps climate change- Around the end of the last ice age, or over hunting)
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Cause of the straight evolutionary lines were unknown Perhaps some kind of force internal to the organism led to transformations Complexity Evolutionary inertia
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Theodor Eimer developed an eclectic view of evolution based on five different causes 1) the direct influence of external conditions 2) the functional activity of organisms in relation to the external world (use and disuse) 3) The struggle for existence 4) “Sexual mixing, which may, without any influence of adaptation, lead to the production of new forms.” 5) The sudden appearance of new formations (evolution per saltum ).
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