The "disposable soma" theory for the evolution of senescence suggests that senescence arises from an optimal balancing of resources between reproduction and somatic repair. Dynamic programming models are constructed and analyzed to determine the optimal relationship between reproduction, diversion of resources from repair, and added senescent mortality. Of particular interest is the relationship between the repair-reproduction trade-off and the form of the mortality-rate-versus-age curve predicted. The models analyzed in the greatest detail assume that the relationship between reproduction and added senescent mortality does not change with age. These suggest that mortality should increase at an increasing rate with age, but may approach a linear rate as mortality becomes very high. General results are derived for the shape of the mortality curves early and late in the senescing part of the life span, and mortality curves for specific trade-off functions are illustrated. An exponential increase in death rate with age (Gompertz' Law) corresponds to only one of many possible relationships between reproduction and aging. The "Law" is unlikely to hold generally if the disposable soma theory accounts for a large fraction of the observed senescent increase in mortality with age. However, support for the generality of Gompertz' Law is weak, and other theories have not produced an evolutionary explanation for the law. The disposable soma theory is consistent with some of the exceptions to Gompertz' Law that have been observed.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/j.1558-5646.1995.tb04433.x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Biodemography of Human Aging (Gompertz-Makeham Law) Applied to Surgical Mortality Modeling: A Retrospective National Cohort Study.
Anesthesiology
December 2024
Department of Anaesthesiology, University of Auckland, Grafton, New Zealand; Department of Anaesthesia and Perioperative Medicine, Auckland City Hospital, Grafton, New Zealand.
Article Synopsis
- The Gompertz-Makeham law illustrates a specific mortality pattern where death rates are stable from ages 18 to 30 and increase exponentially thereafter, and its applicability to surgical populations has not been previously analyzed.
- This study investigated a large New Zealand surgical dataset to assess the relationship between age and 1-month postoperative mortality, revealing that the law does indeed apply across various patient groups and conditions.
- Findings indicate that after age 30, there is a notable rise in mortality risk, particularly for high-risk categories, suggesting significant implications for understanding surgical risks and improving surgical risk models.
Study on quality characteristics, shelf-life prediction and frying mass transfer of breaded tilapia nuggets.
Heliyon
September 2024
Gaozhou Natural Aquatic Products Co., Ltd, Maoming, 525200, China.
Deep-fried breaded tilapia nuggets (DFBTNs) have good market prospects as a tilapia deep-processed product. In this study, we used pre-optimized DFBTNs to simulate the mass change from storage to consumption and investigated the changes in storage shelf-life and frying mass transfer kinetics of DFBTNs. Microbial growth trend and shelf-life prediction models at different storage temperatures were developed using a modified Gompertz equation.
View Article and Find Full Text PDF[Prediction of liberation cutting intensity effect on the growth of Korean pine in secondary forest based on double dummy variable model].
Ying Yong Sheng Tai Xue Bao
June 2024
2 Baihe Forestry Bureau of Jilin Province, Yanbian 133613, Jilin, China.
Article Synopsis
- "Planting conifer and reserving broadleaved tree" is a method for restoring broad-leaved pine forests in Northeast China, specifically focusing on the Korean pine's growth under varying liberation cutting intensities.
- The study developed a growth model to analyze how different cutting practices (no cutting, light, medium, heavy, and clear cutting) impact metrics like diameter at breast height (DBH) and tree height.
- Findings suggest that increased liberation cutting intensity leads to significant growth enhancements in DBH (up to 933.3%) over 80 years, with optimal prediction accuracy achieved through a double dummy variable model.
Invariances in relations between aging, exposure to external hazards, and mortality reflected in life table aging rate (LAR) patterns examined through the lens of generalized Gompertz-Makeham law.
Biogerontology
November 2024
Department of Carcinogenesis and Oncogerontology, N.N. Petrov National Medical Research Center of Oncology, 68 Leningradskaya ul., Pesochny-2, Saint Petersburg, 197758, Russia.
According to the Gompertz law, the age-dependent change in the logarithm of mortality (life-table aging rate, LAR) is equal to the population-averaged age-independent biological aging rate (γ), and LAR would be constant if aging were the only cause of mortality increase. However, LAR is influenced by population exposures to the external hazards. If they were constant, according to the Gompertz-Makeham law (GML), LAR would be below γ at lower ages and asymptotically and monotonically approach γ with increasing age.
View Article and Find Full Text PDFCompensation effect of mortality is a challenge to substantial lifespan extension of humans.
Biogerontology
October 2024
NORC at the University of Chicago, 1155 East 60th Street, Chicago, IL, 60637, USA.
Despite frequent claims regarding radical extensions of human lifespan in the near future, many pragmatic scientists caution against excessive and baseless optimism on this front. In this study, we examine the compensation effect of mortality (CEM) as a potential challenge to substantial lifespan extension. The CEM is an empirical mortality regularity, often depicted as relative mortality convergence at advanced ages.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!