Extinction is ubiquitous in natural systems and the ultimate fate of all biological populations. However, the factors that contribute to population extinction are still poorly understood, particularly genetic diversity and composition. A laboratory experiment was conducted to examine the influences of environmental variation and genotype diversity on persistence in experimental Daphnia magna po...

The assumption of the individual effective dose is the basis for the probit method used for analyzing dose or concentration-response data. According to this assumption, each individual has a uniquely innate tolerance expressed as the individual effective dose (IED) or the smallest dose that is sufficient to kill the individual. An alternative to IED, stochasticity suggests that individuals do n...

background : metronidazole, as one of the most widely used antibiotics in the world, in addition to various benefits, has significant adverse effects on the environment and animals. the catalytic ozonation process is one of the most successful methods for antibiotics removal. however, it should be noted that this process, like other oxidation processes, has some byproducts that can be toxic in ...

Exposure of nontarget populations to agricultural chemicals is an important aspect of global change. We quantified the capacity of natural Daphnia magna populations to locally adapt to insecticide exposure through a selection experiment involving carbaryl exposure and a control. Carbaryl tolerance after selection under carbaryl exposure did not increase significantly compared to the tolerance o...

In this paper, we analyze the convergence of a second-order numerical method for the approximation of a size-structured population model whose dependency on the environment is managed by the evolution of a vital resource. Optimal convergence rate is derived. Numerical experiments are also reported to demonstrate the predicted accuracy of the scheme. Also, it is applied to solve a problem that d...

Herbivore-plant interactions have been well studied in both terrestrial and aquatic ecosystems as they are crucial for the trophic transfer of energy and matter. In nutrient-rich freshwater ecosystems, the interaction between primary producers and herbivores is to a large extent represented by Daphnia and cyanobacteria. The occurrence of cyanobacterial blooms in lakes and ponds has, at least pa...

We show that Daphnia magna can be used to assess acute virulence of pathogens relevant to human health, such as Pseudomonas aeruginosa or Photorhabdus asymbiotica. Analysis of bacterial mutants suggests that P. aeruginosa uses similar mechanisms to infect Daphnia and other hosts.