Vegetation and predators mediate color pattern frequencies in Poecilia sphenops Valenciennes
Journal Title: Aquaculture, Aquarium, Conservation & Legislation - International Journal of the Bioflux Society - Year 2008, Vol 1, Issue 1
Abstract
The purpose of the present study was to investigate the body color evolution in Poecilia sphenops under different environmental conditions (aquaria vs. Peţea Lake and Băile Felix spring) and to explain what is the destiny of a non-natural color pattern when the domesticated population is moved in the wild. We concluded color patterns evolve step by step from the ornamental full-black to the ancestral phenotype, in aquaria. Although the black phenotype is one generally limited to some domesticated strains, we found it highly and natural conserved in the wild. Our observations revealed a lot of vegetation in both Peţea Lake and Băile Felix spring, where floating leaves created a darkness underwater. The darker is the water in the lakes, the higher is the chance of a black fish to escape from predators. According to ”natural selection theory”, the black phenotypes of Poecilia sphenops could be conserved in the population, or even natural produced there. When predators preferentially prey on the less pigmented individuals, the black ones (both males and females) have an increased fitness. Consequently, according to ”sexual selection theory” darker females with a preference for darker males will have a higher fitness than darker females which have no such a preference. Black males have an advantage to inseminate more females and produce more black progeny. In this way, the cumulative effect of natural and sexual selection maintain the mutant and fancy black phenotypes in the feral molly populations.
Authors and Affiliations
Valentin Petrescu-Mag, Radu Lozinsky, László Csép, Ruxandra Petrescu-Mag
Extraction of lipids and purification of linoleic acid from Clarias macrocephalus oi
Fatty acid composition of “keli” (Clarias macrocephalus) oil has been shown to contain 18.4% of linoleic acid (LA). Oil was obtained from three types of extraction methods namely Blight & Dryer method, Soxhlet method...
[sup][/sup]Acute toxicity of Nigerian crude oil (Bonny Light) to Desmocaris trispinosa (Crustacea, Palaemonidae)
The acute toxic effects of a Nigerian crude oil (Bonny Light) to freshwater shrimp, Desmocaris trispinosa were studied in toxicity bioassay. The test organisms were exposed to crude oil in a static renewal bioassay...
Consumers’ perceptions on urban water services and connection to sustainable behavior
The paper presents the results of a survey on urban consumers of tap water and public water services. We discuss seven types of awareness and perceptions an their connexion to sustainable behavior: consumers’ awareness o...
Particular disposal of muscular component iin prostate of nutria (Myocastor coypus, Rodentia, Myocastoridae).
Prostate sampled from three nutria males was processed for histological examination. It was found that, unlike terrestrial mammals, the capsula and conjunctive trabeculae not contain smooth muscle cells, so they do not p...
The human impact on benthic community structure and dynamics of different ecosystems from Lunca Mureșului Nature Park (West of Romania).
The anthropic impact, which takes various forms, changes the water quality parameters and disturb the living environment of benthic macroinvertebrates. The present study aims to track the way pollution sources influence...