Endocrine disruption compounds (EDC) are known to affect reproduction, development, and growth of exposed organisms. Although in vertebrates, EDCs mainly act through steroid receptors (e.g. androgen estrogen receptors), their absence many invertebrates suggests the involvement another biological pathway endocrine effects. As retinoid signaling is present almost all Metazoa its gastropods (i.e. ...

A leading hypothesis for the evolutionary maintenance of sexual reproduction proposes that sex is advantageous because it facilitates adaptation. Changes in the environment stimulate adaptation but not all changes are equivalent; a change may occur along one or multiple environmental dimensions. In two evolution experiments with the facultatively sexual rotifer Brachionus calyciflorus, we test ...

A study was carried out in restored South West Lake and non-restored East Lake, of Beira lake with the objective of determining the species composition, density and distribution of zooplankton. Water was sampled from the surface and at a depth of 1 m, from February to March, 2005 between 0900-1130 h. Three rotifers species; Brachinonus calyciflorus, Keratella tropica, Filinia sp., three cladoce...

The toxicity of leachates from two municipal solid waste (MSW) landfills in Southern Italy was characterized using a toxicity identification evaluation procedure. The chemical and physical fractionation techniques were: pH adjustment, pH adjustment/filtration, pH adjustment/C(18) solid phase extraction, graduated pH and EDTA chelation. All the samples exhibited acute toxicity towards the bacter...

Little information is known about bioaccumulation of atrazine or the effects it has on consumers that ingest atrazine-contaminated prey. For that reason, freshwater microalgae Chlorella vulgaris cultures were exposed to different concentrations of atrazine for twenty-four hours and were then used as an exclusive food source for Brachionus calyciflorus for three days with the intent to evaluate ...