Nomogenesis
Berg is most well known for his evolutionary theory called nomogenesis, which was a type of orthogenesis. Berg's ideas were collected in his book Nomogenesis; or, Evolution Determined by Law and was first published in 1922 in Russia; it was later translated into English in two editions the first appearing in 1926 and the later edition appearing in 1969. In the book Berg collected a large amount of empirical data which offered a strong criticism of Darwin's theory of evolution.
Berg's theory of nomogenesis combined arguments from paleontology, zoology and botany to claim that evolution is not a random process. The theory of Nomogenesis emphasized the limitations of natural selection which determine the directionality of evolution.
Berg claimed that the variation of characters in species is confined within certain limits due to both internal and external factors. The limitation of the variability, Berg argued, left hardly any space for natural selection; he claimed this was supported by the paleontological record because all the phylogenetic branches look more or less like straight lines. Berg distanced himself from both Darwinism and Lamarckism. Instead he proposed the concept of directed mass mutations as the main mechanism for directing evolution.
Influenced by the paleontologist Wilhelm Waagen, he labeled the directed mutations Waagen-Mutations:
"New species arise by means of mass transformation of a great number of individuals, which happens due to Waagen mutations... This mass transformation is a phenomenon of geological magnitude. It is connected with the alteration of the fauna of a certain horizon and comes about in certain periods only to be absent for a long time"
Thus Berg claimed evolution was caused by mass mutations, which are directed by internal and external factors, so that new species occur with a high probability of being almost perfectly adapted. According to Berg, newly evolved species beget the subordinate taxonomic categories, and appear to be perfectly adapted to their environments. Although Berg's theory was anti-Darwinian, and anti-Lamarckian, it still advocated adaptive evolution.
J B S Haldane called Nomogenesis "by far the best anti-Darwinian book of this century".
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