In this article we propose that the mechanism that gave rise to the diversity of living systems that we find today, as well as to the biosphere as coherent system of interrelated autonomous living systems, is natural drift. And we also propose that that which we biologists connote with the expression natural selection is a consequence of the history of the constitution of the biosphere through natural drift, and not the mechanism that generates that history. Moreover, we do this by proposing: a) that the history of living systems on earth is the history of the arising, conservation, and diversification of lineages through reproduction, and not of populations; b) that biological reproduction is a systemic process of conservation of a particular ontogenic-phenotype/ontogenic- niche relation, and not a genetic process of conservation of some genetic constitution; c) that a lineage arises in the systemic reproductive conservation of an ontogenic-phenotype/ontogenic-niche relation, and not in the conservation of a particular genotype; d) that although nothing can happen in the life history of a living system that is not permitted by its total genotype, whatever happens in it arises in an epigenetic manner, and it is not possible to properly claim that any features that arises in the life history of an organism is genetically determined; e) that it is behavior what guides the course of the history of living systems, not genetics; and f) that that which a taxonomist distinguishes when he or she claims that an organism belongs to a particular species, is a particular ontogenic phenotype/ontogenic niche relation that occupies a nodal position in the historical diversification of lineages