Negligible senescence and aging theories

Negligible Senescence Issues

For non adaptive hypotheses as Wear and Tear Hypothesis, Mutation Accumulation Hypothesis, Antagonistic Pleiotropy Hypothesis, Disposable Soma Hypothesis, the age-related decline should be universal for all the species.

But many species in the wild show no age-related mortality increase [Finch 1990]. This means or 1) that the hypotheses are false or 2) that, for unknown causes, they are valid only for part of the species.

"For species whose individuals survive till considerable ages in the wild and that at the greater ages found in the wild show no detectable fitness reduction, viz. in the case of the “animals with negligible senescence” (e.g., rockfish, sturgeon, turtles, bivalve mollusks, certain perennial trees and possibly lobsters [Finch 1990]), this looks really strange and provokes noteworthy doubts [Finch & Austad 2001]. These cases require to be explained with physiologic peculiarities, viz. for non-adaptive hypothesis such animals and plants must be considered as exceptions justified by further particular hypothesis. However, particular optimization models of life-history strategies based on disposable soma theory assumptions [Kirkwood 1977]; [Kirkwood & Holliday 1979] have been developed to justify even the case in which survival increases at greater ages [Vaupel et al. 2004]." [Libertini 2008]

However, these particular models have the taste of ad hoc explanations.

References:
- Finch, C.E. (1990) Longevity, Senescence, and the Genome. University of Chicago Press, Chicago. [Google Scholar]
- Finch, C.E. & Austad, S.N. (2001) History and prospects: symposium on organisms with slow aging, Exp. Gerontol. 36, 593-597. [PubMed] [Google Scholar]
- Kirkwood, T.B.L. (1977) Evolution of ageing. Nature 270, 301-304. [PubMed] [Google Scholar]
- Kirkwood, T.B.L. & Holliday, R. (1979) The evolution of ageing and longevity. Proc. R. Soc. Lond. B. Biol. Sci. 205, 531-546. [PubMed] [Google Scholar]
- Libertini G. (2008) Empirical evidence for various evolutionary hypotheses on species demonstrating increasing mortality with increasing chronological age in the wild. TheScientificWorldJOURNAL 8, 182-93 DOI 10.1100/tsw.2008.36. [PubMed] [Google Scholar] [Free]
- Vaupel, J.W., Baudisch, A., Dolling, M., Roach, D.A. and Gampe, J. (2004) The case for negative senescence. Theor. Popul. Biol. 65(4):339-51. [PubMed] [Google Scholar]