The degree to which, and rapidity with which, inbreeding depression can be purged from a population has important implications for conservation biology, captive breeding practices, and invasive species biology. The degree and rate of purging also informs us regarding the genetic mechanisms underlying inbreeding depression. We examine the evolution of mean survival and inbreeding depression in s...

Carcharhinus limbatus has a cosmopolitan distribution and marked genetic structuring, mainly because of its philopatric behavior. However, analysis of this structuring has not previously included South American populations. In the present study, we analyzed a sample of adult individuals collected on the northern coast of Brazil and compared the sequences of the mitochondrial control region with...

t a s p c w e e s e P a u a p p l t b We studied the behavior and biology of the Australian parasitoids Syngaster lepidus Brullé and Callibracon limbatus (Brullé) (Hymenoptera: Braconidae), which are being introduced into California as biological control agents of the eucalyptus longhorned borer, Phoracantha semipunctata F. (Coleoptera: Cerambycidae). Studies conducted in Australia revealed tha...

The seed beetle Stator limbatus adjusts egg size in response to the quality of the oviposition host, laying small eggs on the high quality host, Acacia greggii seeds, and larger eggs on the poor quality host, Cercidium floridum seeds. We examined various proximate mechanisms of this egg-size plasticity. Once exposed to a new host, it takes 24 to 48 h for females to change the size eggs they lay...

Body size of many animals varies with latitude: body size is either larger at higher latitudes (Bergmann's rule) or smaller at higher latitudes (converse Bergmann's rule). However, the causes underlying these patterns are poorly understood. Also, studies rarely explore how sexual size dimorphism varies with latitude. Here we investigate geographic variation in body size and sexual size dimorphi...

The genus Antodynerus de Saussure, 1855 is reviewed from the Indian subcontinent. Three species with one additional subspecies are present, namely Antodynerus flavescens flavescens (Fabricius, 1775), A. f. karachiensis Giordani Soika, 1970, A. limbatus (de Saussure, 1852), and A. punctatipennis (de Saussure, 1853). The parasitic association of strepsipteran insects and the symbiotic association...

Body size of many animals increases with increasing latitude, a phenomenon known as Bergmann's rule (Bergmann clines). Latitudinal gradients in mean temperature are frequently assumed to be the underlying cause of this pattern because temperature covaries systematically with latitude, but whether and how temperature mediates selection on body size is unclear. To test the hypothesis that the "re...

In many organisms, large offspring have improved fitness over small offspring, and thus their size is under strong selection. However, due to a trade-off between offspring size and number, females producing larger offspring necessarily must produce fewer unless the total amount of reproductive effort is unlimited. Because differential gene expression among environments may affect genetic covari...

Several hypotheses have been proposed to explain the evolution of polyandry in species that provide nuptial gifts. When nuptial gifts are in the form of nutritional elements in the ejaculate and ejaculate size is correlated with male body size, females can accrue both direct (nutritional) and indirect (genetic) benefits from multiple mating. We examined remating decisions in females of the seed...