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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

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GONADECTOMY EXTENSION. "For example, lifespan of semelparous annual plants can often be artificially extended by removing reproductive structures. 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." View in LinkedIn

EXECUTIONER'S REPRIEVE. "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." View in LinkedIn

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