Facing the green threat: A waterflea's defenses against a carnivorous plant

Water fleas of the family Daphniidae are keystone species in many lentic ecosystems and, as most abundant filter feeders, link the primary production to higher trophic levels. As a response to the high predatory pressures, water fleas have evolved a range of defenses, including inducible defenses against animal predators. Here we show in Ceriodaphnia dubia a first example of such defenses induced by the presence of a coexisting plant predator, i.e. the carnivorous southern bladderwort (Utricularia australis, Lentibulariaceae), which possesses ultrafast underwater suction traps. When the bladderwort is present, C. dubia shows changes in morphology, life-history and behavior. While the morphological and behavioral adaptations improve C. dubias survival rate in the presence of this predator, the life-history parameters likely reflect trade-offs for the defense. Our study demonstrates plant-induced animal defenses, implying their potential relevance in freshwater ecosystems and contributing to an overall yet underestimated biodiversity of inducible defenses. Open Research StatementData is not finally prepared for upload yet. Once most fitting file types are determined and metadata is created we aim to upload all raw data as supporting information.