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LAST FLING. "In some cephalopod molluscs, rapid senescence and death follow spawning (squids) or brooding (octopuses). For example, in Octopus hummelincki, brooding females alter and reduce feeding behavior and die shortly after their eggs hatch. These traits are influenced by endocrine secretions from the optic gland." View in LinkedIn

NO LAST REQUESTS. "Among invertebrates, cases of death following semelparous reproduction that clearly seem to be coded into the genome (and thus “programmed”) include the many insects in which adults entirely lack mouthparts or are otherwise incapable of feeding." View in LinkedIn

DEATH SIGNAL. "Males of several small marsupials die shortly after mating. Remarkably, the proximate molecular mechanisms of decline and death in all these distantly related vertebrates seem to be similar, with corticosteroid stress hormones playing the central role." View in LinkedIn

LAST ACT. "Semelparous animals show a similar pattern. Among vertebrates, the best studied examples of rapid senescence and death following semelparous reproduction are in fishes and marsupial mammals. Anadromous Pacific salmon (Oncorhynchus spp.), and catadromous eels (Anguilla spp.) and lampreys (Petromyzontidae) die shortly after spawning." View in LinkedIn

HORMONAL EXECUTIONER. "Semelparity is common in long-lived plants, occurring in representatives of at least 20 different families. In most cases, the proximate mechanisms of death are unknown, but there is evidence in some species for an internally generated “senescence signal”, which may be a hormone." (Semelparity = single reproductive event before death). View in LinkedIn

REFERENCE FOR TODAY: Are Internal, Death-Promoting Mechanisms Ever Adaptive?" "John W Pepper, Deborah E Shelton, Armin Rashidi, and Pierre M Duran. (This reference refuses to post normally on LI). View in LinkedIn

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