Biogenetic Haeckel-Mueller Law

The biochemical law of Haeckel-Muller describes the relationship observed in living nature - ontogeny, that is, the personal development of each living organism, to a certain extent it repeats phylogenesis - the historical development of the entire group of individuals to which it belongs. The law was formulated, as the name implies, E. Haeckel and F. Müller in the 60s of the XIX century independently of each other, and it is almost impossible to establish the pioneer of the theory.

Obviously, the biogenetic law was not formulated immediately. The work of Mueller and Haeckel was preceded by the creation of a theoretical basis for the law in the form of already discovered phenomena and other established laws of nature. In 1828 K. Baer formulated the so-called law of germ-like similarity. Its essence lies in the fact that embryos of individuals belonging to the same biological type have many similar elements of anatomical structure. In humans, for example, at a certain stage of development, the embryo has gill slits and a tail. The characteristic distinctive features in the morphology of species arise only in the course of further ontogeny. The law of embryonic similarity largely determined the biogenetic law: since the embryos of different organisms repeat the stages of development of other individuals, they repeat the stages of development of the whole type in general.

A.N. Severtsov later made certain amendments to the Haeckel-Mueller law. The scientist noted that during embryogenesis, that is, the stage of embryonic development, there is a similarity between organs of embryos, and not of adults. Thus, the gill slits of the human embryo are similar to the gill slits of fish embryos, but not to the newly formed gills of adult fish.

It is important to note that one of the most significant evidences of the Darwinian theory of evolution is biogenetic law itself. His formulation itself hints at its own logical connection with the teachings of Darwin. The embryo passes through many different stages during its development, each of which resembles certain stages of development of nature, marked from an evolutionary point of view. Thus, each more and more complexly organized individual reflects in his ontogeny the development of the entire living nature from the point of view of evolution.

In psychology, there is also a biogenetic law, formulated independently of biological. As a matter of fact, in psychology, an unconstrained law is singled out, and the idea expressed by I. Herbart and T. Ziller about the similarity of the development of the child's psyche with that of mankind in general. Various scientists have tried to substantiate this theory from different points of view. G. Hall, for example, resorted directly to the Haeckel-Muller law. He said that the development of the child, including in the psychological sense, is given exclusively by biological prerequisites and repeats evolutionary development in general. Anyway, today the idea is not unequivocally proven. In psychology, there is still no biogenetic law as such.