In this contribution, we present an endogenous growth model which essentially extends the idea of the paper by Murphy, Riddell and Romer (1998). In that paper, the authors assume that technical progress leads to wage differentials between high-skilled workers and unskilled workers. As technical progress occurs, the relative marginal productivity of different input changes. Yet, if there is suff...

In many developing countries today, the structural transformation is a shift of employment out agriculture into service sector. By contrast, industrial mostly stagnant. Is sector an engine growth and hence led? Or its expansion mere corollary growth, where rising incomes stemming from productivity in goods-producing industries increases demand for services? To determine whether led or biased, w...

Stalk-eyed flies (family Diopsidae) are a model system for studying sexual selection due to the elongated and sexually dimorphic eye-stalks found in many species. These flies are of additional interest because their X chromosome is derived largely from an autosomal arm in other flies. To identify candidate genes required for development of dimorphic eyestalks and investigate how sex-biased expr...

Sex allocation theory predicts that facultative maternal investment in the rare sex should be favoured by natural selection when breeders experience predictable variation in adult sex ratios (ASRs). We found significant spatial and predictable interannual changes in local ASRs within a natural population of the common lizard where the mean ASR is female-biased, thus validating the key assumptio...

Weaponry in ungulates may be costly to grow and maintain, and different selective pressures in males and females may lead to sex-biased natural survival. Sexual differences in the relationship between weapon growth and survival may increase under anthropogenic selection through culling, for example because of trophy hunting. Selection on weaponry growth under different scenarios has been largel...

This study was intended to find out any possible effect of topic bias on the writing proficiency of Iranian extrovert/introvert EFL learners at high/low writing proficiency levels. One hundred participants chosen from among 150 adult language learners on the basis of their personality type (extrovert/introvert) and writing proficiency (high/low) took part in this study. They were arranged into ...

Growth and reproductive attributes were determined for Capoeta damascina, an endemic fish species from west of Iran. A total of 147 specimens of both sexes were sampled monthly from November 2008 to October 2009. The overall sex ratio was female biased. Males were aged 0-4 years and females 0-5 years. The von Bertalanffy growth parameters were estimated as Linf=34.81 cm, k=0.27 year-1, t0=-0.65...