Hybrid zones allow for the investigation of incipient speciation and related evolutionary processes of selection, gene flow, and migration. Interspecific dynamics, like competition, can impact the size, shape, and directional movement of species in hybrid zones. Hybrid zones contribute to a paradox for the biological species concept because interbreeding between species occurs while parental fo...

The omnipresence of microplastics and nanoparticles has led to their entry into the fresh marine aquatic systems affected biota. present study aims evaluate impact interaction polyethylene microplastic (PE-MPs) zinc oxide (ZnO-NPs) in mosquito fish, Gambusia holbrooki. For this, fish were exposed 100 µg L−1 PE-MPs (group 2), 200 3), 50 ZnO-NPs 4), combined with 5), 6) control 1) for 14 days. as...

Key to predicting impacts of predation is understanding the mechanisms through which predators impact prey populations. While consumptive effects are well-known, non-consumptive predator effects (risk effects) are increasingly being recognized as important. Studies of risk effects, however, have focused largely on how trade-offs between food and safety affect fitness. Less documented, and appre...

The long-fingered bat Myotis capaccinii is a European trawling bat reported to feed on fish in several Mediterranean locations, but the ecological circumstances of this behavior have not yet been studied. To elucidate the importance of fishing in this bat's diet, we evaluated the frequency and seasonal variation of fish remains in 3,000 fecal pellets collected from M. capaccinii at a nursery ro...

In most livebearing fish, the gravid spot is an excellent marker to identify brooding females, however its use to predict progress of embryonic development, brood size, timing of parturition and overall reproductive potential of populations remain unexplored. Therefore, to understand these relationships, this study quantified visual attributes (intensity and size) of the gravid spot in relation...

In social animal groups, an individual's spatial position is a major determinant of both predation risk and foraging rewards. Additionally, the occupation of positions in the front of moving groups is generally assumed to correlate with the initiation of group movements. However, whether some individuals are predisposed to consistently occupy certain positions and, in some instances, to consist...

Previous studies demonstrated differential mortality among mosquitofish of different Gpi-2 genotypes during acute mercury and arsenate exposures. Mercury-exposed mosquitofish also had Gpi-2 genotype-specific differences in glycolytic and Krebs cycle metabolite pools. The mortality and metabolite data suggested that mosquitofish bearing specific Gpi-2 genotypes might differ in metabolic efficien...

Melanin-based color patterns are an emerging model for studying molecular and evolutionary mechanisms driving phenotypic correlations. Extensive literature exists on their correlated traits in the family Poeciliidae, indicating that these fishes tractable models. We review biology of polymorphic melanic side-spotting characterized by macromelanophores forming irregular spotted across fishes’ fl...

This study tests the sensitivity of genetically based pest control options based on sex ratio distortion to intra- and intersexual aggressive interactions that affect male and female survival and fitness. Data on these interactions and their impacts were gathered for the mosquitofish Gambusia holbrooki (Poeciliidae), a promiscuous species with a strongly male-biased operational sex ratio and we...