The compensation law of mortality (or late-life mortality convergence) states that the relative differences in

death rate Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time. Mortality rate is typically expressed in units of de ...

s between different populations of the same biological species decrease with age, because the higher initial death rates in disadvantaged populations are ''compensated'' by lower pace of mortality increase with age. The age at which this imaginary (extrapolated) convergence of mortality trajectories takes place is named the "species-specific life span" (see Gavrilov and Gavrilova, 1979). For human beings, this human species-specific life span is close to 95 years (Gavrilov and Gavrilova, 1979; 1991). Compensation law of mortality is a paradoxical empirical observation, and it represents a challenge for methods of

survival analysis Survival analysis is a branch of statistics for analyzing the expected duration of time until one event occurs, such as death in biological organisms and failure in mechanical systems. This topic is called reliability theory or reliability analysi ...

based on proportionality assumption (proportional hazard models). The compensation law of mortality also represents a great challenge for many theories of

aging Ageing ( BE) or aging ( AE) is the process of becoming older. The term refers mainly to humans, many other animals, and fungi, whereas for example, bacteria, perennial plants and some simple animals are potentially biologically immortal. In ...

and

mortality Mortality is the state of being mortal, or susceptible to death; the opposite of immortality. Mortality may also refer to: * Fish mortality, a parameter used in fisheries population dynamics to account for the loss of fish in a fish stock throug ...

, which usually fail to explain this phenomenon. On the other hand, the compensation law follows directly from

reliability theory Reliability engineering is a sub-discipline of systems engineering that emphasizes the ability of equipment to function without failure. Reliability describes the ability of a system or component to function under stated conditions for a specifi ...

, when the compared systems have different initial levels of redundancy.

References

*Gavrilov LA, Gavrilova NS.
Reliability Theory of Aging and Longevity.
In: Masoro E.J. & Austad S.N.. (eds.): ''Handbook of the Biology of Aging'', Sixth Edition. Academic Press. San Diego, CA, USA, 2006, 3-42. *Gavrilov LA, Gavrilova NS. ''Why We Fall Apart. Engineering's Reliability Theory Explains Human Aging''.

IEEE Spectrum ''IEEE Spectrum'' is a magazine edited by the Institute of Electrical and Electronics Engineers. The first issue of ''IEEE Spectrum'' was published in January 1964 as a successor to ''Electrical Engineering''. The magazine contains peer-revie ...

, 2004, 41(9): 30–35. *Gavrilov L.A., Gavrilova N.S. "The quest for a general theory of aging and longevity". Science's ''SAGE KE'' (''Science of Aging Knowledge Environment'') for 16 July 2003; Vol. 2003, No. 28, 1–10. https://www.science.org/loi/sageke, *Gavrilov L.A., Gavrilova N.S
The reliability theory of aging and longevity
''Journal of Theoretical Biology'', 2001, 213(4): 527–545. *

Leonid A. Gavrilov The reliability theory of aging is an attempt to apply the principles of reliability theory to create a mathematical model of senescence. The theory was published in Russian by Leonid A. Gavrilov and Natalia S. Gavrilova as ''Biologiia prodol ...

& Natalia S. Gavrilova (1991), ''The Biology of Life Span: A Quantitative Approach''. New York: Harwood Academic Publisher, *Gavrilov, L.A., Gavrilova, N.S. "Determination of species length of life". ''

Doklady Akademii Nauk SSSR The ''Proceedings of the USSR Academy of Sciences'' (russian: Доклады Академии Наук СССР, ''Doklady Akademii Nauk SSSR'' (''DAN SSSR''), french: Comptes Rendus de l'Académie des Sciences de l'URSS) was a Soviet journal that ...

'', 1979, 246(2): 465–469. English translation by Plenum Publ Corp: pp. 905–908. *Gavrilov, L.A. "A mathematical model of the aging of animals". ''Doklady Akademii Nauk SSSR'', 1978, 238(2): 490–492. English translation by Plenum Publ Corp: pp. 53–55. *Gavrilov, L.A., Gavrilova, N.S., Yaguzhinsky, L.S. "The main regularities of animal aging and death viewed in terms of reliability theory". ''J. General Biology'' 'Zhurnal Obschey Biologii'' 1978, 39(5): 734–742. {{Death Population Senescence

See also

References