Practice question

Life-history theory emphasizes a trade-off between current reproductive effort and future reproduction. Energy devoted now to gametes, offspring, courtship, or care cannot also support growth, repair, immune defense, and survival to later breeding. Increasing present output may therefore reduce the number or quality of future offspring, while restrained investment can preserve residual reproductive value. Semelparity and iteroparity describe timing, whereas fecundity describes output. Long juvenile development can occur with either strategy. Ecologists therefore examine complete schedules of survival and reproduction rather than inferring strategy from lifespan alone. Closely related species may differ when adult mortality or the payoff from concentrated effort changes. Reading the terms biologically, rather than memorizing labels, shows how individual survival and reproduction scale up to population change. Ecological predictions remain conditional on the stated environment, because changing resources, mortality, or interactions can alter the observed demographic pattern. This interpretation connects individual-level processes with measurable changes in survival, reproduction, recruitment, or abundance across the population.