Life, Its Definition, Origin, Evolution, and Four-dimensional Hierarchical Structure, Biosystems

The main unique features of biological systems are reviewed, and four necessary and sufficient attributes of life are formulated, based on the ideas of Ervin Bauer.

The possibility of the occurrence of each of these attributes during the origin of life is analyzed. As a result, different scenarios for the origin of life are presented, with all their pros and cons. Next, the mainstream of biological evolution is discussed, considering it as a special case of general complexification, and structuredness is defined as a quantitative measure of structural complexity.

By introducing the concepts of post-dissipative structure and ratcheting process based on “frozen” patterns, their role in the generation of biological structures underlying biological evolution is demonstrated. Furthermore, it is proposed that all living things can be divided into micro- (unicellular) and macro- (multicellular) creatures, which differ from each other even more radically than the difference between prokaryotes and unicellular eukaryotes.

Then the fifth, sufficient, but not necessary attribute of life, hierarchicality, is formulated, which is fully applicable only to macrolife. It is also shown that living organisms are primarily chemodynamic rather than thermodynamic systems, and three basic laws of biochemodynamics are formulated. Finally, fifteen basic features of living beings, grouped into four basic blocks, are summarized.

George E. Mikhailovsky
https://doi.org/10.1016/j.biosystems.2024.105158

Life, Its Definition, Origin, Evolution, and Four-dimensional Hierarchical Structure, Biosystems, Science Direct

Astrobiology