Abstract
Environmental stochasticity impacts population dynamics and their
viability. As such, understanding how organisms cope with this
variability is crucial. Here, we investigate demographic buffering, the
ability of populations to maintain stable growth despite environmental
fluctuations. We integrate well-established stochastic and deterministic
approaches to investigate characteristics of demographic buffering,
analysing stochastic elasticities and self-second derivatives of
deterministic population growth rate. We test the hypothesis that
buffered species exhibit low stochastic elasticity to temporal
variability and signs of concave selection (i.e. negative second
derivatives of population growth rate with respect to demographic
processes), reducing variance in key demographic processes. Analysing 43
natural populations of 37 mammal species, we find limited support for
this hypothesis. Indeed, while primates often show low stochastic
elasticity, concave selection is less prevalent than expected. Our
findings highlight the complex and dynamic relationship between
demographic processes, environmental variability, and selection
pressures in determining population persistence.