Diapause in Cladocera: mechanisms of induction, termination and seasonal information accumulation

ABSTRACT Diapause is a crucial seasonal adaptation underpinning the dominance of Cladocera in temperate and ephemeral aquatic ecosystems worldwide. The induction of diapause is regulated by environmental cues, including photoperiod, temperature, predator kairomones and population density, with sensitivity to these cues shaped by non-genetic, transgenerational inheritance via maternal effects. The subsequent production of dormant ephippial eggs facilitates genetic exchange and creates egg banks that ensure population resilience. The remarkable viability of diapausing Daphnia embryos exposed to the extreme conditions of spaceflight underscores the profound robustness of this adaptive strategy. This review synthesizes findings from laboratory, field and space experiments to elucidate diapause as a complex, bio-informative system driving seasonal adaptation, bridging classic works on Cladocera ecology by Prof. Gliwicz with modern insights into dormancy’s evolutionary significance.