This psychism that coordinates the vital functions makes use of the senses and the memory) for the perception of variations in the environment. These senses, which through time have become more complex (like all parts of organisms), provide information on the environment that will be structured in adaptative orientation. The environment in turn is very varied, and certain minimal environmental conditions are necessary for the organism’s development. Wherever these physical conditions are present, life emerges; and once the first organisms appear, the conditions are progressively transformed in way that is increasingly more favorable for life. But in the beginning, organisms require optimal environmental conditions for development. The variations in the troposphere reach all organisms. Thus, daily cycles and seasonal cycles, as well as general temperature, radiation and solar light, are influential conditions in the development of life. So is the composition of the Earth, which, in its wealth, offers raw material that will be the energy and work source for living beings. The accidents that can occur all over the planet are also decisive circumstances for organic development. From glaciations, cave-ins, earthquakes and volcanic eruptions, even wind and water erosion—all are determining factors. Life will be different in the deserts, in the mountain heights, on the poles or on the seacoasts. Large numbers of organisms and diverse species appear and disappear from the earth’s surface once life arrives from the oceans. Many individuals encounter insurmountable difficulties and perish as a result. This also happens to complete species—species that were unable to transform themselves or the new situations that arose in the evolutionary process. Life nonetheless continually opens up its path, encompassing many possibilities through great numbers and diversity.
When diverse species appear within one same space, different relations arise among them, apart from those that exist within the same species. There are relations of symbiosis, of association, parasitic relations, saprophytic relations and so on. All these possible relations can be simplified into three major types: relations of domination, relations of interchange, and relations of destruction. Organisms maintain these relationships among themselves, with some surviving and others disappearing.
We are dealing with organisms with functions that are regulated by a psychism; organisms equipped with senses to perceive the internal and external environments, and with a memory that is not just genetic memory for the trans-mission of the species’ characteristics (instincts” of reproduction and conservation), but also individual recordings of new reflexes that make it possible to decide in front of alternatives. The memory also fulfills another function: the register of time; memory makes it possible to give continuity to the passing of time. The first circuit of short reflexes (stimuli-response) allows for variations in its complexity, thus allowing specialization of the nervous and endocrine systems. On the other hand, the possibility of acquiring new reflexes originates learning and domestication, also enabling specialization of multiple mechanisms of response. As a result, variable behavior can be observed; variable conduct in the environment, in the world.
After many attempts by Nature, mammals began their development, producing different and numerous cases. These mammals gave rise to different branches, among them the hominids of recent date. From hereon in, the psychism begins a specific development.