Lamarck for the win verses Weismann's Barrior and NeoDarwinism


Neo-Darwinism, also known as the Modern Synthesis, is the narrow majority belief of how evolution works. This has changed rapidly over the last 10 years and should be eclipsed by the next 10 years. It is based on the theory of natural selection, which was first proposed by Charles Darwin, and the Mendelian laws of genetics, which were discovered by Gregor Mendel.

August Weismann was a German biologist who is best known for his criticism of Lamarckism, the theory that acquired characteristics can be inherited. Weismann argued that the germ cells, which give rise to all the other cells in the body, are separate from the somatic cells, and that changes in the somatic cells cannot be inherited. This is known as the Weismann barrier.

Weismann's criticism of Lamarckism was based on a post hoc experiment. For example, he showed that if you cut off the tails of mice, the offspring of those mice did not have shorter tails. This showed that the acquired characteristic of having a shorter tail was not inherited. Although this was a mutilization experiment having little to do with Lamarck. Indeed if he noticed the offspring hed have noted that they would have characteristics of PTSD for 3-4 generations.

Weismann's work helped to establish a theory of inheritance, which is based on the theory of genes. "Gene Centrism". Genes are passed from parents to offspring, and they determine the characteristics of the offspring. Acquired characteristics were thought to not occur.

Weismann's criticism of Lamarckism eventually became the dominant view in biology. However Lamarckism is on the rebound due to epigenetics. The Weismann barrier was seen as a way to explain why Lamarckian inheritance, the idea that acquired characteristics can be inherited, is not possible.

Recent research has shown that the Weismann barrier is not impermeable as once thought. There is now evidence that epigenetic changes, which are changes in gene expression that are not caused by changes in DNA sequence, can be inherited. This means that it is possible for acquired characteristics to be passed on to offspring.

The Modern Synthesis also excluded epigenetics, the study of changes in gene expression that are not caused by changes in DNA sequence. Epigenetic changes can be caused by environmental factors, such as diet, stress, and exposure to toxins. They can also be inherited from parents to offspring.

The Modern Synthesis did not incorporate epigenetics. However, in recent years, epigenetics has become a major area of research in biology. There is now a growing body of evidence that epigenetic changes can play a role in evolution.

So, while the Weismann barrier and the Modern Synthesis did exclude soft inheritance and Lamarckism, respectively, there is now strong evidence that these processes occurs. Epigenetic inheritance is still a relatively new field of research, and there is much that we do not yet know about it. However, it is clear that epigenetics has the potential to revolutionize our understanding of evolution.

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