As the classical Breeder’s Equation often fails to accurately predict evolutionary responses, concepts of ‘total’ heritability incorporating ‘non-genetic inheritance’, such as maternal effects (MEs), have been explored. Despite ample evidence for MEs in a variety of traits and theoretical indications for their evolutionary importance, the consequences of MEs for evolutionary responses in natural populations remain unclear. We here explored whether MEs can alter the rate of adaptation of a key life-history trait, clutch size, undergoing directional selection following an environmental shift (e.g. when increased phenological mismatch due to climate warming leads to a smaller optimal clutch size). To test this, we parameterized an individual-based model with data from a long-term (1973–2013) study of great tits (Parus major). Using these realistic parameter values we show that MEs, whether ‘environmentally plastic’ or fixed, have little effect on evolutionary responses. This demonstrates the importance of using realistic parameters values in theoretical models and questions the importance of MEs for adaptation to environmental changes, such as climate change.
|Publication status||Published - 2017|