title: Extremely short lifespan in the annual fish Nothobranchius furzeri.
abstract: Evolutionary theories of senescence postulate that lifespan is determined by the age-dependent decrease in the effects of natural selection. Factors that influence survival and reproduction at early life stages have a larger impact on fitness than factors that influence later life stages. According to these views, selection for rapid sexual maturation and a steep age-dependent decrease in fitness drive the evolution of short lifespans. Here, we report on the survival trajectory of Nothobranchius furzeri (Pisces: Ciprinodontidae): a member of a group of annual species found in temporary bodies of water whose life expectancy in the wild is limited to a few months. We find that maximum survival of N. furzeri in the laboratory is less than 12 weeks. The temporal trajectory of survival shows an age-dependent increase in the mortality rate that is typical of organisms with defined lifespans. The lifespan of N. furzeri is exceptionally short for a vertebrate: owing to its small size and the possibility of propagation in captivity, N. furzeri could be used as a convenient model for ageing research.
authors.affiliation: Associazione Italiana Killifish, Canossa 42026, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Valdesalici
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cellerino
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D001824:Body Constitution / Q000502:physiology; D023781:Fundulidae / Q000502:physiology*; D008136:Longevity / Q000502:physiology*