Why we should not necessarily expect life history strategies to inform on sensitivity to environmental change

Background/Question/Methods

Speed of life and reproductive strategy form the two major axes that organise variation in life history strategies across plant and animal species. This cross-taxonomical structuring can inform on the sensitivity of species to environmental change. However, predictions based on broad cross-taxonomical patterns do not necessarily align with those from detailed research on a smaller range of species. One reason for this discrepancy could be that life history trade-offs assumed to underlie life history structuring do not align with patterns in traits across species. Here, we use Dynamic Energy Budget Integral Projection Models (DEB-IPMs) to quantify the extent to which patterns in the life history strategies of a large and diverse taxonomic class of fish (Actinopterygii) inform on their sensitivity to environmental change. We explicitly account for the energetic investment trade-off into growth versus reproduction, and reproductive decisions.

Results/Conclusions

By accounting for additional complexity in individual life histories, we find that the classical association between life history strategies and sensitivity to environmental change breaks down. We discuss which trait-based approach is best suited to tackle challenges in linking life histories to population responses to change, and summarise our perspective on these challenges in a conceptual framework.