Search results for "Offspring"
showing 10 items of 395 documents
Influence of male mating history on female reproductive success among monandrous Naryciinae (Lepidoptera: Psychidae)
2011
1. Multiple male copulations can have detrimental effects on female fitness due to sperm limitation. 2. Monandrous Naryciinae females are immobile while the males are short-lived and do not feed. Multiple male mating is therefore expected to lead to sperm limitation in females. Sperm limitation and male limitation are hypothesised as causes of the repeated evolution of parthenogenetic reproduction in the Psychidae. 3. In this study, the effects of multiple male mating on female reproduction are investigated in several species of Naryciinae by allowing males multiple copulations. The results for two species, Siederia listerella and Dahlica lichenella, are compared. The sex ratios of 53 natur…
High cognitive sensitivity to activational effects of testosterone in parents of offspring with autism spectrum disorders
2014
Abstract The existence of mild forms of autistic-like characteristics in parents of children with autism spectrum disorders (ASDs) has been defined as a broader autistic phenotype (BAP). Excessive prenatal exposure to testosterone (T) seems to play a role in its development. The aims of this study were to characterize whether ASD parents show masculinized brains or high T prenatal exposure compared to a normative population, using cognitive questionnaires, and also to examine the T level changes in response to different cognitive tasks. ASD parents were found to present higher autistic and lower empathic trait scores than controls. They also have higher T levels and magnitude of T response …
Evidence for a teratogenic risk in the offspring of health personnel exposed to ionizing radiation?!
2016
Background The evidence concerning safety of occupational exposure to ionizing radiation on teratogenic effects mainly relies on animal models, disaster epidemiology and experience in cancer etiology. Following an explorative result on maternal exposure in medical occupations we conducted a feasibility study, addressing congenital anomalies (CA) in the offspring of health workers potentially exposed to radiation. Methods In a prospective follow-up study, we enrolled women, identified by mandatory registration at the office of radiation protection as wearing a dosimeter. The participating women answered a questionnaire and if pregnant agreed to an examination of their infant. CA were diagnos…
The M74 syndrome of baltic salmon (Salmo salar) and organochlorine concentrations in the muscle of female salmon
1997
Abstract Organochlorine concentrations in the muscle of female Baltic salmon (Salmo salar), ascending for spawning in the Simojoki River on the north-eastern coast of the Gulf of Bothnia from 1988 to 1992 are given in this paper in relation to reproduction success, monitored as viability of offspring. In spring 1992 and 1993 all the yolk-sac fry of 52 % and 75 % of the females, sampled in autumns 1991 and 1992 respectively, died due to the M74 syndrome, i.e., heavy mortality of yolk-sac fry (YSM). The TEOs of the most frequently detected polychlorinated dibenzofurans (PCDFs: 1,2,3,7,8-PeCDF, 2,3,4,7,8-PeCDF and 2,3,7,8-TeCDF) and those of coplanar PCBs (CB77, CB126 and CB169) were about twi…
Parent-Child Similarity in Environmental Attitudes: A Pairwise Comparison
2012
Are adolescents’ environmental attitudes similar to their parents’ attitudes? The main objective of this study is to examine what quantitative associations, if any, exist in parent-child environmental attitudes within the family. The survey data was collected assessing attitudes toward the environment and nature from 15-year-old students (n = 237) and their parents (n = 212) in Finland. A significant positive correlation emerged in environmental attitudes between mothers and fathers. Interestingly, the results revealed some indicative evidence that girls’ environmental attitudes could relate more to their father's than mother's attitudes. Girls were as positive in their environmental attitu…
Quantitative genetic analysis of Cry1Ab tolerance in Ostrinia nubilalis Spanish populations
2013
30 p.-2 fig.-3 tab.
Sexual and natural selection on body mass and metabolic rates in free-living bank voles
2010
Summary 1. Because energy is a crucial resource, adaptive significance of variation in the rate of energy metabolism, and especially in basal (BMR) and maximum aerobic (VO2max) metabolic rates, is a popular theme in evolutionary and ecological physiology. However, little is known about the association of these traits with fitness components in populations of free-living animals. 2. We studied the association between body size, the metabolic rates, and reproductive success in bank voles (Myodes glareolus) in an isolated, small island population. Correlation analyses were performed for two measures of reproductive performance: mating success (the number of partners with which an individual ha…
Effects of population outcrossing on rotifer fitness
2010
Abstract Background Outcrossing between populations can exert either positive or negative effects on offspring fitness. Cyclically parthenogenetic rotifers, like other continental zooplankters, show high genetic differentiation despite their high potential for passive dispersal. Within this context, the effects of outcrossing may be relevant in modulating gene flow between populations through selection for or against interpopulation hybrids. Nevertheless, these effects remain practically unexplored in rotifers. Here, the consequences of outcrossing on the rotifer Brachionus plicatilis were investigated. Cross-mating experiments were performed between a reference population and three alterna…
Good-genes effects in sexual selection
1999
The magnitude of the effect of good genes as a viability benefit accruing to choosy females remains a controversial theoretical and empirical issue. We collected all available data from the literature to estimate the magnitude of good-genes viability effects, while adjusting for sample size. The average correlation coefficient between male traits and offspring survival in 22 studies was 0.122, which differed highly significantly from zero. This implies that male characters chosen by females reveal on average 1.5% of the variance in viability. The studies demonstrated considerable heterogeneity in effect size; some of this heterogeneity could be accounted for by differences among taxa (birds…
Mate choice for offspring performance: major benefits or minor costs?
1998
There is considerable disagreement over whether or not gaining viability benefits to offspring could be substantial enough to overcome the costs of female choosiness. A recent review suggested that the 'lek paradox' might be resolved by large indirect benefits as indicated by highly heritable ornamental traits. We selected males of a wolf spider Hygrolycosa rubrofasciata in relation to their sexual signalling rate (audible drumming). The estimated correlated response in offspring viability was rather small (0.12 s.d.). However, it may be large enough if the costs of being choosy are small. In fact, females mate with better-than-average males just by responding passively to a random drumming…