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SURGICAL LIFE EXTENSIONS. "Optic gland removal in O. hummelincki causes cessation of brooding, reinstates normal feeding behavior, and extends life. In fishes, removal of the gonads (Pacific salmon, lampreys) or of the pituitary gland (lampreys) and prevention of mating (eels) can substantially increase life span. Similarly in small marsupials, castration or prevention of mating can increase male life span up to that of females." https://lnkd.in/ecP3KMX View in LinkedIn

FAILURE TO CROSS. “The intervals after mass extinctions tend to be significantly enriched in taxa that failed to cross the next stage boundary, relative to other intervals before the extinction event; in other words more clades that survived a mass extinction tend to dwindle or disappear shortly after the event than would be expected by chance.” https://lnkd.in/epHhn4i) View in LinkedIn

MANIPULATION OF GRIM REAPER. "In both plants and animals, life span can be is extended by experimental manipulations of physiology and/or reproduction, indicating that senescence is not the inevitable outcome of physical constraints. For example, lifespan of semelparous annual plants can often be artificially extended by removing reproductive structures." https://lnkd.in/ecP3KMX View in LinkedIn

ITEROPAROUS ORGANISMS "have multiple reproductive episodes during the life cycle, as opposed to a solitary event. In these species, senescence leading to death is less abrupt and dramatic, but is ubiquitous nonetheless. Although data are difficult to collect, a high rate of death due to senescence in iteroparous species has been documented for some species even in the wild." https://lnkd.in/ecP3KMX View in LinkedIn

HOLIN-ANTIHOLIN SYSTEMS. "A similar puzzle arises in the case of holin-antiholin systems, which are encoded by bacteriophages and control the timing of host cell lysis and the dispersal of virions. Chromosomally-encoded homologs are biochemically distinct from toxin-antitoxin systems, but also result in cell death." https://lnkd.in/ecP3KMX View in LinkedIn

TOXIN-ANTITOXIN SYSTEMS. "In prokaryotes, conjugative plasmids often encode for the simultaneous production of long-lived toxins and short-lived antitoxins. When these are present together, the toxin is harmless to the host. However, if one daughter cell is cured of the plasmid, it will inherit toxic cytoplasm without a source of antitoxin and will die." Train driver’s Dead Man’s Switch. https://lnkd.in/ecP3KMX View in LinkedIn

TRANSPOSONS KILLING THE HOST. "This process may be associated with occurrence of new mutations in the transferred genes and their improved ability to survive in the new host. This mechanism has been suggested to occur in S. cerevisiae although the author allows that, “this hypothesis lacks direct experimental support”. https://lnkd.in/ecP3KMX View in LinkedIn

MOBILE ELEMENTS. "Genetic elements have been closely studied that routinely increase their inclusive fitness by killing their host. In some cases, this peculiar form of selection may explain the function and evolution of genes for unicell programmed organismal death When a cell has low chances for reproduction, programmed organismal death and the transfer of genes from the dying cell to a new host can save the genes." https://lnkd.in/ecP3KMX View in LinkedIn

COMPETING INTERESTS. "The reproductive interests of genetic elements can differ from those of the organism carrying them. It is well established that gene-level selection can generate traits that are detrimental to individual fitness, while benefitting smaller genetic entities within them." https://lnkd.in/ecP3KMX View in LinkedIn

DEATH FITNESS IN UNICELLULAR ORGANISMS. "There is considerable experimental evidence for fitness advantages from programmed organismal death to clonal kin groups of cells of species usually considered to be ‘unicellular’. These fitness advantages may represent a significant source of selection pressure." https://lnkd.in/ecP3KMX View in LinkedIn