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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

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

CAMBRIAN PUZZLE. “Abrupt appearance of major bilaterian clades in the fossil record during the first three stages of the Cambrian Period has puzzled the scientific world since 1830s.” https://lnkd.in/ehHwFGP View in LinkedIn

ALTRUISTIC BEES. "One familiar example occurs in honeybee workers, which commit suicide each time they sting invaders in defense of their hive. Similarly, these workers altruistically commit suicide in ways that apparently function to prevent the spread of disease within the hive. In these cases, there is little mystery concerning function or evolution. Kin selection, or equivalently, selection among colonies, is a powerful force shaping the evolution of eusocial insects." https://lnkd.in/ecP3KMX View in LinkedIn

FULL RECOVERY. “It appears likely that for mass extinction episodes in the geological past, the recovery period usually lasted at least five million years.” https://lnkd.in/eyRBipn View in LinkedIn

POST-MATING DEATH IN SPIDERS. "Male self-sacrifice”, or apparent male cooperation with female cannibalism, is part of male copulatory behavior in several spider species, and in some insects. One study also reported that males of the spider Argiope aurantia spontaneously die when they copulate." https://lnkd.in/ecP3KMX View in LinkedIn