Multiple interactions and regulation of life forms with their environment
A presentation on information flow in living systems
Living systems arelife forms (or, more colloquially known asliving things) treated as asystem. They are said to beopenself-organizing and said to interact with their environment. These systems are maintained by flows ofinformation,energy andmatter. Multiple theories of living systems have been proposed. Such theories attempt to map general principles for how all living systems work.
Some scientists have proposed in the last few decades that a general theory of living systems is required to explain the nature of life.[1] Such a general theory would arise out of theecological andbiological sciences and attempt to map general principles for how all living systems work. Instead of examining phenomena by attempting to break things down into components, a general living systems theory explores phenomena in terms of dynamic patterns of the relationships of organisms with their environment.[2]
James Grier Miller's living systems theory is a general theory about the existence of all living systems, theirstructure,interaction,behavior anddevelopment, intended to formalize the concept of life. According to Miller's 1978 bookLiving Systems, such a system must contain each of twenty "critical subsystems" defined by their functions. Miller considers living systems as a type ofsystem. Below the level of living systems, he definesspace andtime,matter andenergy,information andentropy, levels oforganization, and physical and conceptual factors, and above living systems ecological, planetary and solar systems, galaxies, etc.[3][4][5] Miller's central thesis is that the multiple levels of living systems (cells, organs, organisms, groups, organizations, societies, supranational systems) areopen systems composed of critical and mutually-dependent subsystems that process inputs, throughputs, and outputs of energy and information.[6][7][8] Seppänen (1998) says that Miller appliedgeneral systems theory on a broad scale to describe all aspects of living systems.[9]Bailey states that Miller's theory is perhaps the "most integrative" social systems theory,[10] clearly distinguishing between matter–energy-processing and information-processing, showing how social systems are linked to biological systems. LST analyzes the irregularities or "organizational pathologies" of systems functioning (e.g., system stress and strain, feedback irregularities, information–input overload). It explicates the role of entropy in social research while it equatesnegentropy with information and order. It emphasizes both structure and process, as well as their interrelations.[11]
The idea that Earth is alive is found in philosophy and religion, but the first scientific discussion of it was by the Scottish geologistJames Hutton. In 1785, he stated that Earth was a superorganism and that its proper study should bephysiology.[12]: 10 The Gaia hypothesis, proposed in the 1960s byJames Lovelock, suggests that life on Earth functions as a single organism that defines and maintainsenvironmental conditions necessary for its survival.[13][14]
A systems view of life treats environmentalfluxes and biological fluxes together as a "reciprocity of influence,"[15] and a reciprocal relation with environment is arguably as important for understanding life as it is for understanding ecosystems. AsHarold J. Morowitz (1992) explains it, life is a property of anecological system rather than a single organism or species.[16] He argues that an ecosystemic definition of life is preferable to a strictlybiochemical or physical one.Robert Ulanowicz (2009) highlights mutualism as the key to understand the systemic, order-generating behaviour of life and ecosystems.[17]
Robert Rosen devoted a large part of his career, from 1958[18] onwards, to developing a comprehensive theory of life as a self-organizing complex system, "closed to efficient causation". He defined a system component as "a unit of organization; a part with a function, i.e., a definite relation between part and whole." He identified the "nonfractionability of components in an organism" as the fundamental difference between living systems and "biological machines." He summarised his views in his bookLife Itself.[19]
Complex systems biology is a field of science that studies the emergence of complexity in functional organisms from the viewpoint ofdynamic systems theory.[20] The latter is also often calledsystems biology and aims to understand the most fundamental aspects of life. A closely related approach, relational biology, is concerned mainly with understanding life processes in terms of the most important relations, and categories of such relations among the essential functional components of organisms; for multicellular organisms, this has been defined as "categorical biology", or a model representation of organisms as acategory theory of biological relations, as well as analgebraic topology of thefunctional organisation of living organisms in terms of their dynamic, complexnetworks of metabolic, genetic, andepigenetic processes andsignalling pathways.[21][22] Related approaches focus on the interdependence of constraints, where constraints can be either molecular, such as enzymes, or macroscopic, such as the geometry of a bone or of the vascular system.[23]
Harris Bernstein and colleagues argued in 1983 that the evolution of order in living systems and certain physical systems obeys a common fundamental principle termed the Darwinian dynamic. This was formulated by first considering how macroscopic order is generated in a simple non-biological system far from thermodynamic equilibrium, and then extending consideration to short, replicatingRNA molecules. The underlying order-generating process was concluded to be basically similar for both types of systems.[24][25]
Gerard Jagers' operator theory proposes that life is a general term for the presence of the typical closures found in organisms; the typical closures are a membrane and an autocatalytic set in the cell[26] and that an organism is any system with an organisation that complies with an operator type that is at least as complex as the cell.[27][28][29][30] Life can be modelled as a network of inferiornegative feedbacks of regulatory mechanisms subordinated to a superiorpositive feedback formed by the potential of expansion and reproduction.[31]
Definition of cellular life according toBudisa, Kubyshkin and Schmidt
Budisa, Kubyshkin and Schmidt definedcellular life as an organizational unit resting on four pillars/cornerstones: (i)energy, (ii)metabolism, (iii)information and (iv)form. This system is able to regulate and control metabolism and energy supply and contains at least one subsystem that functions as an information carrier (genetic information).Cells as self-sustaining units are parts of differentpopulations that are involved in the unidirectional and irreversible open-ended process known asevolution.[34]
Biological organization – Hierarchy of complex structures and systems within biological sciencesPages displaying short descriptions of redirect targets
Biological systems – Complex network which connects several biologically relevant entitiesPages displaying short descriptions of redirect targets
Complex systems – System composed of many interacting componentsPages displaying short descriptions of redirect targets
Earth system science – Scientific study of the Earth's spheres and their natural integrated systems
Viable System Theory – concerns cybernetic processes in relation to the development/evolution of dynamical systemsPages displaying wikidata descriptions as a fallback
^Clealand, Carol E.; Chyba, Christopher F. (8 October 2007). "Does 'Life' Have a Definition?". In Woodruff, T. Sullivan; Baross, John (eds.).Planets and Life: The Emerging Science of Astrobiology. Cambridge University Press.In the absence of such a theory, we are in a position analogous to that of a 16th-century investigator trying to define 'water' in the absence of molecular theory. [...] Without access to living things having a different historical origin, it is difficult and perhaps ultimately impossible to formulate an adequately general theory of the nature of living systems
^Seppänen, Jouko (1998). "Systems ideology in human and social sciences". In Altmann, G.; Koch, W.A. (eds.).Systems: New paradigms for the human sciences. Berlin: Walter de Gruyter. pp. 180–302.
^Rosen, Robert (1958). "A relational theory of biological systems".The Bulletin of Mathematical Biophysics.20 (3):245–260.doi:10.1007/bf02478302.
^Robert, Rosen (1991).Life Itself: A Comprehensive Inquiry into the Nature, Origin, and Fabrication of Life. New York: Columbia University Press.ISBN978-0-231-07565-7.
^*Rosen, Robert (1958a). "A Relational Theory of Biological Systems".Bulletin of Mathematical Biophysics.20 (3):245–260.doi:10.1007/bf02478302.
^*Rosen, R. (1958b). "The Representation of Biological Systems from the Standpoint of the Theory of Categories".Bulletin of Mathematical Biophysics.20 (4):317–341.doi:10.1007/bf02477890.
^Bernstein, Harris; Byerly, Henry C.; Hopf, Frederick A.; Michod, Richard A.; Vemulapalli, G. Krishna (June 1983). "The Darwinian Dynamic".The Quarterly Review of Biology.58 (2): 185.doi:10.1086/413216.JSTOR2828805.S2CID83956410.
^Michod, Richard E. (2000).Darwinian Dynamics: Evolutionary Transitions in Fitness and Individuality. Princeton: Princeton University Press.ISBN978-0-691-05011-9.
^Jagers, Gerard (2012).The Pursuit of Complexity: The Utility of Biodiversity from an Evolutionary Perspective. KNNV Publishing. pp. 27–29,87–88,94–96.ISBN978-90-5011-443-1.
^Jagers Op Akkerhuis, Gerard A. J. M. (2010). "Towards a Hierarchical Definition of Life, the Organism, and Death".Foundations of Science.15 (3):245–262.doi:10.1007/s10699-010-9177-8.S2CID195282529.
^Jagers Op Akkerhuis, Gerard (2011). "Explaining the Origin of Life is not Enough for a Definition of Life".Foundations of Science.16 (4):327–329.doi:10.1007/s10699-010-9209-4.S2CID195284978.
^Jagers, Gerald (2012). "Contributions of the Operator Hierarchy to the Field of Biologically Driven Mathematics and Computation". In Ehresmann, Andree C.; Simeonov, Plamen L.; Smith, Leslie S. (eds.).Integral Biomathics. Springer.ISBN978-3-642-28110-5.
Miller, J.L., & Miller, J.G. (1992). Greater than the sum of its parts: Subsystems which process both matter-energy and information.Behavioral Science, 37, 1–38.
Humberto Maturana (1978), "Biology of language: The epistemology of reality," in Miller, George A., and Elizabeth Lenneberg (eds.),Psychology and Biology of Language and Thought: Essays in Honor of Eric Lenneberg. Academic Press: 27-63.
Jouko Seppänen, (1998). Systems ideology in human and social sciences. In G. Altmann & W.A. Koch (Eds.),Systems: New paradigms for the human sciences (pp. 180–302). Berlin: Walter de Gruyter.
