Unicellular picocyanobacteria, such as species of the genus Synechococcus, are unsuitable for supporting growth and reproduction of Daphnia spp. In Synechococcus spp., long-chain polyunsaturated fatty acids (PUFAs) and sterols are absent, which leads to a low carbon transfer efficiency at the picocyanobacteria–Daphnia spp. interface. Herein, we address the question as to whether ciliates can se...

In shallow subarctic ponds Daphnia and their algal food are often exposed to solar ultraviolet radiation (UVR). It was previously demonstrated that direct exposure of Daphnia to UVR may result in sublethal damage to Daphnia‘s intestinal system. This led to the hypothesis that, as consequences of such exposures, Daphnia may be experiencing a situation similar to starvation. We examined, in contr...

Despite a significant increase in genomic data, our knowledge of gene functions and their transcriptional responses to environmental stimuli remains limited. Here, we use the model keystone species Daphnia pulex to study environmental responses of genes in the context of their gene family history to better understand the relationship between genome structure and gene function in response to env...

Chemicals released into the environment have a potential to affect on various species and evaluation of the impacts on ecosystems including aquatic organisms is urgent issue. In order to evaluate chemical effects on various species, it is important to understand their mode of action. Recent advances in toxicogenomics, the integration of genomics into toxicology is promising for understanding mo...

Experimental results provide evidence that trophic interactions between ciliates and Daphnia are constrained by the comparatively low food quality of ciliates. The dietary sterol content is a crucial factor in determining food quality for Daphnia. Ciliates, however, presumably do not synthesize sterols de novo. We hypothesized that ciliates are nutritionally inadequate because of their lack of ...

Invasive species have extensive negative consequences for biodiversity and ecosystem health. Novel species also drive contemporary evolution in many native populations, which could mitigate or amplify their impacts on ecosystems. The predatory zooplankton Bythotrephes longimanus invaded lakes in Wisconsin, USA, in 2009. This invasion caused precipitous declines in zooplankton prey (Daphnia puli...

Rapid growth could significantly reduce methylmercury (MeHg) concentrations in aquatic organisms by causing a greater than proportional gain in biomass relative to MeHg (somatic growth dilution). We hypothesized that rapid growth from the consumption of high-quality algae, defined by algal nutrient stoichiometry, reduces MeHg concentrations in zooplankton, a major source of MeHg for lake fish. ...

The water flea Daphnia magna has been used as an animal model in ecology, evolution, and environmental sciences. Thanks to the recent progress in Daphnia genomics, genetic information such as the draft genome sequence and expressed sequence tags (ESTs) is now available. To investigate the relationship between phenotypes and the available genetic information about Daphnia, some gene manipulation...