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REPRODUCTIVE ZENITH. "The strongest appearance of programmed organismal death in organismal senescence is found in semelparous species, which reproduce only once during the life cycle. A common pattern in these species is that individuals appear healthy up to the time of reproduction, then decline rapidly and dramatically afterwards." View in LinkedIn

ADAPTIVE SENESCENCE. "Clearly it can be adaptive for a large organism to cause the senescence of specific organs or structures, such as leaves on a deciduous plant. Whole-organism senescence leading to death is more puzzling, and explaining it has been a long-standing challenge. If a large organism can build itself from a single cell, why can it not maintain itself once built? Or can organismal death actually be adaptive in some cases, in the sense of increasing Darwinian fitness?" View in LinkedIn

GROUP FITNESS. "In some cases of behavioral suicide, particularly in insects, there are distinct advantages to kin and group level benefits may play a role. In unicells, programmed death is ubiquitous and programmed organismal death often provides benefits to others." View in LinkedIn

DEATH AND FITNESS. "In multicellular organisms the program frequently (although not always) appears to be the result of fitness trade-offs. Here the death phenotype itself is not adaptive but the fitness related program most likely is." View in LinkedIn

GENETIC SENESCENCE. "There is substantial evidence for genetic control of senescence in some iteroparous animals, indicating that senescence is at least sometimes “programmed” (in the inclusive sense) and highlighting the question of the relationship between aging “programs” and selection. For example, in Drosophila melanogaster, selective breeding and other studies demonstrated a genetic, heritable component to senescence." View in LinkedIn

SUICIDE AS ADAPTIVE? "The idea that self-inflicted organismal death could be adaptive sounds, at face value, absurd. An adaptation is a trait that is suitable (apt) for the current circumstances or environmental challenges, and archetypal examples include traits that promote survival." View in LinkedIn

SPARING THE PROLIFIC. "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. General explanations for organismal senescence are varied and contentious, and the idea that iteroparous senescence is “programmed” is not the majority view." View in LinkedIn

UNABLE TO POST REFERENCE TO THIS GROUP. Are Internal, Death-Promoting Mechanisms Ever Adaptive?" "John W Pepper, Deborah E Shelton, Armin Rashidi and Pierre M Durand. View in LinkedIn

INTERNAL DEATH CLOCK. "Similarly in small marsupials, castration or prevention of mating can increase male life span up to that of females. These experiments indicate that rapid senescence and death following reproduction in at least some semelparous animals are genetically “programmed” and internally controlled." View in LinkedIn

WIDESPREAD CELL DEATH SYSTEMS. "Are Internal, Death-Promoting Mechanisms Ever Adaptive? Natural selection acts primarily on organisms, and the existence of evolved, active, internal mechanisms that cause organismal death would seem paradoxical. However, there is substantial evidence that internal death promoting mechanisms exist and are taxonomically widespread." View in LinkedIn