It is a challenge to measure sexual selection because both stochastic events (chance) and deterministic factors (selection) generate variation in individuals' reproductive success. Most researchers realize that random events ('noise') make it difficult to detect a relationship between a trait and mating success (i.e. the presence of sexual selection). There is, however, less appreciation of the...

Locomotion is central to behavior and intrinsic to many fitness-critical activities (e.g., migration, foraging), and it competes with other life-history components for energy. However, detailed analyses of how changes in locomotor activity and running behavior affect energy budgets are scarce. We quantified these effects in four replicate lines of house mice that have been selectively bred for ...

Sea-urchin species differ in susceptibility to sperm limitation and polyspermy, but the influences of gamete traits on reproductive variance, sexual selection, and sexual conflict are unknown. I compared male and female reproductive success of two congeners at natural densities in the sea. The eggs of the species occurring at higher densities, Strongylocentrotus purpuratus, require higher sperm...

Beef sire selection decisions have a major impact on future calf crops and ultimately on profitability. Using available selection tools can help make better bull buying choices. A critical place to start when beginning the herd sire selection decision process is to evaluate the cow herd(s) that the sires will service. From these herd assessments, profiles of desirable herd sires can be develope...

emergency medicine is a relatively new specialty in iran. therefore, the general public and the medical community do not have enough information on its duties, capabilities, its nature, and its work schedule or its degree of occupational difficulty compared to other specialties. hence, an insight from the early group of residents who selected this specialty can help identify the strengths and w...

in this paper, the researchers have proposed a multi-dimensional knapsack model for project capital budgeting problem in uncertain situation which has been modeled through fuzzy sets. the optimistic and pessimistic situations were considered and associated deterministic models were yielded. numerical example has been supplied toillustrate the performance of proposed model. the results were prom...

background & aim: german chamomile is one of the most important medicinal plants. so, assessment of genetic diversity and relationship among the traits are very essential in chamomile breeding programs. determination of the best indirect selection criteria for genetic improvement of essence percent and dry flower yield of german chamomile (matricaria chamomilla l.) populations was investiga...

In nature, many animals use intermittent rather than continuous locomotion. In laboratory studies, intermittent exercise regimens have been shown to increase endurance compared with continuous exercise. We hypothesized that increased intermittency has evolved in lines of house mice (Mus domesticus) that have been selectively bred for high voluntary wheel-running (wheel diameter 1.12 m) activity...

A pleiotropic model of maintenance of quantitative genetic variation at mutation-selection balance is investigated. Mutations have effects on a metric trait and deleterious effects on fitness, for which a bivariate gamma distribution is assumed. Equations for calculating the strength of apparent stabilizing selection (V(s)) and the genetic variance maintained in segregating populations (V(G)) w...

The hybrid zone on Mount Etna (Sicily) between Senecio aethnensis and Senecio chrysanthemifolius (two morphologically and physiologically distinct species) is a classic example of an altitudinal cline. Hybridization at intermediate altitudes and gradients in phenotypic and life-history traits occur along altitudinal transects of the volcano. The cline is considered to be a good example of ecolo...