In order to fully satisfy all human's existential needs, he needs to create the immunity to negative factors in his environment, i.e. to block them in a such way, that they wouldn't have the possibility to disturb a person to use his direct energy source or a person has to find a way to prevent those negative factors from destroying the living systems directly. These processes are called adaptation. Adaptation can be full and partial. Partial adaptation - it's when a person adapts to his living environment only partially and is still being heavily affected by negative factors. And full adaptation - it's when a person is completelly adapted to his environment with the efficiency of almost 100%. Adaptation exists everywhere in the Universe, where there is life. Every individual life form has different possibilities to adapt to its environment. Adaptation is the basis for evolution. The concept of adaptation can also be applied to energy cycles, which are not included in living systems. In that case, the weaker energy cycles (which have less energy) in some way adapt to existential needs of the stronger energy cycles. So, in the final result, the stronger energy cycles change physical structure and chemical composition of the weaker energy cycles in such way, that the weaker cycles could make optimal conditions for the stronger cycles to use their structural elements for direct or indirect satisfaction of stronger cycles' existential needs. However, every kind of adaptation has its losses too - while the weaker cycles are adapting to the stronger cycles, both of them are more or less harmed in that process. The stronger cycle inevitably uses part of its own energy, while changing the structure of the weaker cycle for the stronger cycle's benefit. And also the stronger cycle receives some structural losses during that process.