Abstract
The variability of biological matter contributes to both its adaptability and reliability. To represent the structure of this variability we treat a complete biological system (e.g. community and environment) as a system with sets of states and certain (unknown) probabilities governing the state to state transitions. Adaptability (defined operationally in terms of the maximum tolerable uncertainty of the environment) consists of behavioral uncertainty, ability to anticipate the environment, and indifference to the environment. It may also be decomposed into components associated with genetic, organismic, population, and community levels of organization. Considerations of adequate design suggest that adaptability tends to fall to its lowest allowable value in the course of evolution. This means that any change in adaptability associated with one level or unit of organization tends to be compensated by opposite changes in the adaptability associated with other levels or units, or by opposite changes in the indifference to the environment. The analysis shows that the adaptability is not independent of reliability, and that each functionally distinct state consists of: (1) finer states which mediate the processing of information about the environment; (2) redundant sets of such states; and (3) informationally equivalent states associated with macroscopically equivalent microdescriptions.
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Literature
Conrad, M. 1972a. “Statistical and Hierachical Aspects of Biological Organization.” InTowards a Theoretical Biology, Vol. 4, pp. 189–221. C. H. Waddington, ed., Edinburgh: Edinburgh University Press. Also available as Center for Theoretical Studies preprint, No. CTS-B-70-1, Coral Gables, 1970.
— 1972b. “Can There Be a Theory of Fitness?”Int. J. Neurosci.,3, 125–134.
— 1972c. “Stability of Foodwebs and Its Relation to Species Diversity.”J. Theor. Biol.,34, 325–335
— 1975. “Analyzing Ecosystem Adaptability.”Math. Biosci.,27, 213–230.
— 1976. “Patterns, of Biological Control in Ecosystems.” To appear inSystems Analysis and Simulation in Ecology, Vol. 4. pp. 431–456. B. C. Patten, ed. New York: Academic Press. Also available as University of Tübingen preprint, “Patterns of Biological Control,” February, 1973.
Khinchin, A. I. 1957.Mathematical Foundations of Information Theory. New York: Dover.
Margalef, R. 1973. “Some Critical Remarks on the Usual Approaches to Ecological Modeling.”Inv. Pesq.,37, 621–640.
Pattee, H. H. 1968. “The Physical Basis of Coding and Reliablity in Biological Evolution.” InTowards a Theoretical Biology, Vol. 1, pp. 67–93. C. H. Waddington, ed. Edinburgh: Edinburgh University Press.
Rashevsky, N. 1960.Mathematical Biophysics, Physico-Chemical Foundations of Biology, Vol. 2. New York: Dover.
Rosen, R. 1967.Optimality Principles in Biology. New York and London: Butterworth.
— 1970.Dynamical System Theory in Biology, Vol. 1. New York: Wiley-Interscience.
Shannon, C. E. and Weaver, W. 1949.The Mathematical Theory of Communication. Urbana: University of Illinois Press.
Winograd, S. and Cowan, J. D. 1963.Reliable Computation in the Presence of Noise. Cambridge, Mass.: MIT Press.
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Conrad, M. Functional significance of biological variability. Bltn Mathcal Biology 39, 139–156 (1977). https://doi.org/10.1007/BF02462854
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DOI: https://doi.org/10.1007/BF02462854