How differing modes of transgenerational inheritance affect population viability in fluctuating environments

Abstract

1Different modes of transgenerational inheritance are expected to affect population persistence in fluctuating environments. We here analyze Caenorhabiditis elegans density-independent per capita growth rate time series on 36 populations experiencing 6 controlled sequences of challenging oxygen level fluctuations across 60 generations, and parameterize competing models of transgenerational inheritance that do not involve genetic changes in order to explain observed dynamics. Our analysis shows that phenotypic plasticity and anticipatory maternal effects are sufficient to explain growth rate dynamics, but that a carryover model where epigenetic memory is imperfectly transmitted and might be reset at each generation is a better fit to the data. After validating the models, we use the fitted transgenerational inheritance parameters to forecast population growth rates and find that it is negatively related to the degree of environmental autocorrelation.