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In the process of its formation, every living organism has undergone a long and complicated path. Many of its characteristics cannot be properly explained unless the whole history of its philogenetic development is well understood. Evolution as a vehicle of development consisting in continuous or gradual, small quantitative changes within a range of particular quality is no longer disputed. What is still far from clear is whether in order to explain evolutionary processes one should take into account the principle of mutation and natural selection alone. Some other factors may have to be considered as well, such as migration, cross-breeding, and other random factors. The question also arises whether philogenetic development, which is determined by the genotype, depends on other environmental factors.
Charles Darwin observed that parents pass their features onto their children. A certain amount of diffusion in this respect is bound to take place and children who better fit ecological conditions are better off in competition. They also bring forth more numerous progeny than those who do not. Thus, the development of a genus involves a series of accommodating steps. Each hereditary change, although beneficial in terms of natural selection, is to be viewed as an adaptive change in the never-ending process of directional development under changing ecological conditions (Eibl-Eibesfeldt, 1984).
As is well known, the chemical basis of heredity lies with the deoxyribonucleic acid (DNA), an acid of the nucleus of the cell that is built up of two interweaving chain helices. Each link of these two chains is composed of a glucose particle, the phosphate group, and one particle of organic bases: adenine (A), guanine (G), and cytozine (C) or tymine (T). The two helices are “glued” to each other by the bases, where, complementarily, A is linked with T only, and C with G. The linear sequence of the base pairs forms a code containing information about the proper development of an orga