In past decades, a considerable amount of research has been conducted to elucidate the factors that affect the carbon transfer across the cyanobacteria–Daphnia interface. It is well accepted that cyanobacteria are a nutritionally inadequate food source for cladocerans, but the underlying mechanisms are still controversial. Morphological properties, toxicity, and the absence of essential lipids,...

Before 1982, Daphnia retrocurva and Daphnia galeata mendotae were the dominant species of Daphnia in Lake Michigan. Between 1972 and 198 1, Daphnia community structure in the offshore region shifted toward greater dominance of the larger D. galeata mendotae, with Daphniapulicaria, another large species, dominating by 1982. This continued through summer 1984. Shifts in offshore Daphnia community...

We present a work-in-progress computer vision system for detecting behavioral changes of Daphnia magna under the influence of Silver-nanoparticles (Ag-NPs) in water systems. We invented a hardware set up that is able to track multiple Daphnia automatically in concordance with the OECD guideline for Daphnia. Our software design and first image results of the computer vision system are represente...

The genetic background of inducible morphological defences in Daphnia is still largely unknown. Dissolved infochemicals from the aquatic larvae of the phantom midge Chaoborus induce so-called 'neck-teeth' in the first three post-embryonic stages of Daphnia pulex This defence has become a textbook example of inducible defences. In a target gene approach, by using three Daphnia genotypes which sh...

We studied the carbon (C) metabolism in Daphnia when the amount of C (food quantity) and/or the content of biochemical nutrients (food quality) was limiting. Growth performances and C budgets of Daphnia magna (assimilation, faeces egestion, excretion and respiration measured by [(14)C]-tracing) were analysed when animals were raised on different food quantities and concentrations of cholesterol...

Ecological factors are known to cause evolutionary diversification. Recent work has shown that evolution in strongly interacting predator species has reciprocal impacts on ecosystems. These divergent impacts of predators may alter the selective landscape and cause the evolution of prey. Yet, this link between intraspecific variation and evolution is unexplored. We compared the life history of a...

Ecological genomics aims to understand the functional association between environmental gradients and the genes underlying adaptive traits. Many genes that are identified by genome-wide screening in ecologically relevant species lack functional annotations. Although gene functions can be inferred from sequence homology, such approaches have limited power. Here, we introduce ecological regulator...

1. The growth rate hypothesis predicts positive relationships among growth rate (l), body RNA (%RNA of dry mass) and body P (%P of dry mass) contents. 2. We tested this withinand across-species by growing five species/clones of Daphnia (Daphnia magna, Daphnia pulex, Daphnia galeata and two isolates of Daphnia pulicaria) with different combinations of food quantity and stoichiometric food qualit...

The effects of fish predation on zooplankton communities are well documented, but relatively little is known about how predation structures the genetic composition of individual populations. This study illustrates how a perturbation in the timing and strength of predation by rainbow trout directly and indirectly altered the genetic composition of a Daphnia pulicaria population in a Minnesota (U...