the main aim of this research was to estimate the genetic and phenotypic parameters for productive and reproductive traits of esfahan native chickens. traits included body weights at hatch (bw1), 8 weeks of age (bw8), 12 weeks of age (bw12), and at sexual maturity (wsm)], age at sex maturity (asm), egg number (en), average egg weight (aew) in the first 12 weeks of production, and egg production...

Studies of sexual selection show that both female choice and male-male competition can influence the evolution and expression of male phenotypes. In this regard, it is important to determine the functional basis through which male traits influence variation in male reproductive success. In this study, we estimate the strength and type of sexual selection acting on adult males in a population of...

We gathered information on the functional traits of the most representative copepod species in the Mediterranean Sea. Our database includes 191 species described by 7 traits encompassing diverse ecological functions: minimal and maximal body length, trophic group, feeding type, spawning strategy, diel vertical migration and vertical habitat. Cluster analysis in the functional trait space reveal...

Species' life history traits, including maturation age, number of reproductive bouts, offspring size and number, reflect adaptations to diverse biotic and abiotic selection pressures. A striking example of divergent life histories is the evolution of either iteroparity (breeding multiple times) or semelparity (breed once and die). We analysed published data on salmonid fishes and found that sem...

heritability, environmentaland genetic correlations between body weight at hatch (bw0), eight (bw8) and twelve (bw12) weeksof age, body weight at sexual maturity (bwm), age at sexual maturity (afe),the weight of the first egg laid by the hen (ewm), the mean egg weight from 28 to 32 wks (ew28-32) and egg numbers (ens) were estimated by the restricted maximum likelihood method under an animal mod...

this study was conducted to investigate direct and maternal effects on some economic traits in north iranian native fowls. traits considered were body weight at 1 day of age (bw1), body weight at 8 weeks of age (bw8), body weight at 12 weeks of age (bw12), egg number (en) during the first 12 weeks of laying period, egg weight at 1st day of laying (ew1), mean egg weight at 28th, 30th and 32nd we...

Geographic variations in body build and physiological traits in human populations are very large. Such qualities of the human species—Homo sapiens—were acquired over a very long period as humans settled the world, but were based upon highly developed plasticity of morpho-physiological traits for this species. Adaptation to new environments when humans were settling the world was accomplished no...