Several authors agree to the fact that August Weismann was the first to propose an explanation to biological aging (Kirkwood and Cremer, 1982; Gems and Partridge, 2013).
A lot of hallmarks (and some contradictory) are pointed out about Weismann along his life, which I am reflecting only in these
- When he suggested that group selection was the answer of aging;
August Weismann and Alfred Russel Wallace proposed that aging has evolved to remove worn-out older individuals, thereby reducing competition for scarce resources and resulting in benefits for the species. However, such an evolutionary mechanism would require group selection of a sort that makes this an untenable scenario. (Gems and Partridge, 2013)
the reason suggested by Weismann for the evolution of ageing was an adaptive one, namely that ageing is beneficial in ridding a species of old and decrepit individuals which would otherwise compete for resources with younger ones. Thus, by natural selection the somatic cells of the organism would have come to lose their capacity for unlimited survival, and ageing of the organism as a whole would have appeared. (Kirkwood and Cremer, 1982)
I don't understand how any of those arguments can justify the evolution of aging
they claim that group selection was responsible for the evolution of aging but it doesn't explain how older individuals get old.. they are just removed from the population because they got old, it doesn't seem to explain the evolution of ageing.
- When he developed the concept of panmixia to reshape his nonadaptive theory (or neutral) of biological aging.
The central component of Weismann's non-adaptive theory of ageing was the principle of panmixia which he developed [...] In brief, this principle states that as soon as any character becomes useless to an organism, natural selection ceases to operate upon it and it begins to disappear. (Kirkwood and Cremer, 1982)
How the concept of panmixia is related to the evolution of aging?
is that because since post-reproductive period does not contribute to the evolution of the species, the potential of immortality of somatic cells desapear? It doesn't make much sense..
- Gems, D. and Partridge, L. (2013) ‘Genetics of longevity in model organisms: Debates and paradigm shifts’, Annual Review of Physiology, 75, pp. 621–644. doi: 10.1146/annurev-physiol-030212-183712
- Kirkwood, T. B. L., & Cremer, T. (1982). Cytogerontology since 1881: A reappraisal of August Weismann and a review of modern progress. Human Genetics, 60(2), pp. 101–121. https://doi.org/10.1007/BF00569695