What is the EVOLUTIONARY advantage of death?

Hi sidelined,
I don't think you can disconnect death from reproduction. Natural selection will favor genes that enhance fitness i.e. ability to reproduce even at the expense of longevity. A lot of the developmental process (not to mention reproduction itself) is costly in terms of oxygen radical production and other chemical byproducts that are toxic. Over time this will be harmful to th organism. In experiments with C. elegans where the sex cells are ablated early in development, there is an average increase in lifespan (going from memory it was almost as large as calory restirction i.e. 30% increase). Eunuchs tend to live as long as women. All in all there is a high cost of reproduction which ultimately leads to death.There were really only two possible strategies for life (with a lot of variation allowed for one of the two).First, the first or close to the first replicators are indestructable, no real selection for reproduction, no real logic for replicators either. Basically an immortal population.Second, replicators survive by copying themselves...a nice tautology but the original replicators could only insure their survival by producing more copies of themselves which is a process that continues to this very second. The strategy insures that more replicators are produced without any safeguards to protect the original replicator. The same way my children would carry (some) of my genes but I will die..yet, my DNA has passed to the next generation.The thread title is a bit strange. What would be the advantage without death? Immortal reproducing organisms? What biosphere could support such a population? You either have organisms that don't die and don't reproduce, or organisms with an expiration date and a hereditary mechanism.

Hi phil,
Another thing to keep in mind is there is intense selection for an individual to reproduce. But once you have reproduced or have gotten beyond the age of reproduction, there is no selection...you will not pass on any genes or you already have. There is no selection pressure to get older. However, age varies tremendously in the population and among organisms and so far, most of the genes underlying this variation seem to be related to development or reproduction. Though some are related to cell maintenance such as DNA damage repair.Metabolism. 2003 Oct;52(10 Suppl):5-9. Related Articles, LinksGenes of aging.Hamet P, Tremblay J.According to developmental genetics theories, aging is a genetically programmed and controlled continuum of development and maturation. Being dynamic and malleable processes, development and aging are controlled not only by genes but also by environmental and epigenetic influences that predominate in the second half of life. Genetic mutations affect many phenotypes in flies, worms, rodents, and humans which share several diseases or their equivalents, including cancer, neurodegeneration, and infectious disorders as well as their susceptibility to them. Life span and stress resistance are closely linked. Oxidative stress actually constitutes a defined hypothesis of aging in that macromolecule oxidative damage accumulates with age and tends to be associated with life expectancy. DNA methylation, a force in the regulation of gene expression, is also one of the biomarkers of genetic damage. The mitotic clock of aging is marked, if not guided, by telomeres, essential genetic elements stabilizing natural chromosomic ends. The dream of humans to live longer, healthy lives is being tested by attempts to modify longevity in animal models, frequently by dietary manipulation. The quest continues to understand the mechanisms of healthy aging, one of the most compelling areas of research in the 21st century