We compute an accurate approximation to the probability of fixation for a beneficial mutation in a population fluctuating with a stationary distribution of population size. The population dynamics are described by the theta-logistic model with environmental variance, assuming that the population size is large enough to ignore demographic variance. We show that stochastic fluctuations of population size reduce the probability of fixation. However, it is not the magnitude of the population fluctuations per se that creates this reduction. Only the environmental variance has a substantial effect on the probability of fixation. The strength of density dependence (or expected return time to equilibrium) and the functional form of density-regulation, given by the parameter θ in the theta-logistic model, have little effect on the fixation probability. Effective population size based on harmonic mean population size will therefore underestimate the expected fixation rate of beneficial mutations in fluctuating populations.

This article explores the changing meaning of Indianness during the long independence era. Focusing on six towns around Santa Marta, it discusses why these were considered Indian in the late colonial period, why they supported the royalist cause during the Independence struggles and how their inhabitants ceased to be identified as Indians within a few decades of republican rule. While recent subaltern studies have emphasised Indian resistance against the liberal, republican states formed in early nineteenth-century Latin America, here it is argued that some former Indian communities opted for inclusion into the republic as non-Indian citizens.

The study of marriageways in colonial Latin America has altered and deepened our understanding of the societies and cultures within the Spanish and Portuguese empires of the New World. During the last thirty or forty years a series of studies have explored the complex and varied patterns of marriage and family formation in colonial Latin America. Inspired by the work of Peter Laslett, Lawrence Stone and Louis Flandrin among others, historians of the region have produced a rich historical literature on the demographic, social and cultural aspects of colonial marriageways. Most studies have focused on the late colonial period, and the years after 1778 when the Pragmática sanción de matrimonios (first issued in Spain in 1776) was extended to Spanish America. One effect of the new law was an astonishing outpouring of reports, questions, lawsuits and regulations concerning marriage, which in turn have been seized upon by historians to reconstruct important aspects of late colonial Latin American societies. Despite the frequent use of these sources, the legislation itself has received little serious attention, and several basic misunderstandings prevail regarding its background and meaning. As a consequence, the political implications of marriage have been poorly understood.

Gastrointestinal evacuation of inert X-ray dense marker by turbot, Psetta maxima, was followed by use of radiography. Groups of individually tagged turbot aged 1 + years (136.5 g), were held at 16 °C and acclimatized to a feeding period of 4 hours per day. Fish were fed on pelleted feed in excess. The experimental design allowed a test of the effects of handling stress and post-prandial feeding on gastrointestinal evacuation. Repeated handling affected feed intake, but there were no significant treatment effects on gastrointestinal evacuation rate. Fish that ingested large meals displayed higher evacuation rates of markers than fish which ingested smaller meals, but total evacuation time was longer for the fish that consumed the largestmeals. Marker particles started to be voided from the gastrointestinal tract approximately 10 hours following initiation of a meal. and evacuation of marker was completed within 52 hours under the holding conditions employed in the present study.