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INTERNAL TRIGGERS. "These experiments indicate that rapid senescence and death following reproduction in at least some semelparous animals are genetically “programmed” and internally controlled." https://lnkd.in/ecP3KMX View in LinkedIn

DIVERSITY EXPLOSIONS. “The most dramatic and creative evolutionary role of mass extinctions is the promotion of postextinction diversifications, typified most vividly by the exuberant radiation of the mammals after the demise of the dinosaurs and other reptilian clades at or near the end-Cretaceous boundary.” https://lnkd.in/epHhn4i) View in LinkedIn

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

ENDOCRINE DEATH TRIGGERS. "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." https://lnkd.in/ecP3KMX View in LinkedIn

PROGRAMMED DEATH. "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. In some cephalopod molluscs, rapid senescence and death follow spawning (squids) or brooding (octopuses)." https://lnkd.in/ecP3KMX View in LinkedIn

STRESS HORMONES AND DEATH. "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." https://lnkd.in/ecP3KMX View in LinkedIn

POST BREEDING DEATH. "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." https://lnkd.in/ecP3KMX View in LinkedIn

SEMELPARITY AND DEATH. "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." https://lnkd.in/ecP3KMX View in LinkedIn