Search results for "Maternal Behavior"
showing 10 items of 37 documents
Not all sex ratios are equal : the Fisher condition, parental care and sexual selection
2017
The term ‘sex roles’ encapsulates male–female differences in mate searching, competitive traits that increase mating/fertilization opportunities, choosiness about mates and parental care. Theoretical models suggest that biased sex ratios drive the evolution of sex roles. To model sex role evolution, it is essential to note that in most sexually reproducing species (haplodiploid insects are an exception), each offspring has one father and one mother. Consequently, the total number of offspring produced by each sex is identical, so the mean number of offspring produced by individuals of each sex depends on the sex ratio (Fisher condition). Similarly, the total number of heterosexual matings …
Parent–offspring conflict and the genetic trade-offs shaping parental investment
2015
The genetic conflict between parents and their offspring is a cornerstone of kin selection theory and the gene-centred view of evolution, but whether it actually occurs in natural systems remains an open question. Conflict operates only if parenting is driven by genetic trade-offs between offspring performance and the parent's ability to raise additional offspring, and its expression critically depends on the shape of these trade-offs. Here we investigate the occurrence and nature of genetic conflict in an insect with maternal care, the earwig Forficula auricularia. Specifically, we test for a direct response to experimental selection on female future reproduction and correlated responses i…
Negative association between parental care and sibling cooperation in earwigs: a new perspective on the early evolution of family life?
2015
International audience; The evolution of family life requires net fitness benefits for offspring, which are commonly assumed to mainly derive from parental care. However, an additional source of benefits for offspring is often overlooked: cooperative interactions among juvenile siblings. In this study, we examined how sibling cooperation and parental care could jointly contribute to the early evolution of family life. Specifically, we tested whether the level of food transferred among siblings (sibling cooperation) in the European earwig F orficula auricularia (1) depends on the level of maternal food provisioning (parental care) and (2) is translated into offspring survival, as well as fem…
Inbreeding depression in an insect with maternal care: influences of family interactions, life stage and offspring sex.
2013
Although inbreeding is commonly known to depress individual fitness, the severity of inbreeding depression varies considerably across species. Among the factors contributing to this variation, family interactions, life stage and sex of offspring have been proposed, but their joint influence on inbreeding depression remains poorly understood. Here, we demonstrate that these three factors jointly shape inbreeding depression in the European earwig, Forficula auricularia. Using a series of cross-breeding, split-clutch and brood size manipulation experiments conducted over two generations, we first showed that sib mating (leading to inbred offspring) did not influence the reproductive success of…
Crocodile egg sounds signal hatching time.
2008
Summary Crocodilians are known to vocalize within the egg shortly before hatching [1,2]. Although a possible function of these calls — inducing hatching in siblings and stimulating the adult female to open the nest — has already been suggested, it has never been experimentally tested [1–5]. Here, we present the first experimental evidence that pre-hatching calls of Nile crocodile ( Crocodylus niloticus ) juveniles are informative acoustic signals which indeed target both siblings and mother.
HORMONAL MANIPULATION OF OFFSPRING NUMBER: MATERNAL EFFORT AND REPRODUCTIVE COSTS
2002
We used exogenous gonadotropin hormones to physiologically enlarge litter size in the bank vole (Clethrionomys glareolus). This method allowed the study design to include possible production costs of reproduction and a trade-off between offspring number and body size at birth. Furthermore, progeny rearing and survival and postpartum survival of the females took place in outdoor enclosures to capture salient naturalistic effects that might be present during the fall and early winter. The aim of the study was to assess the effects of the manipulation on the growth and survival of the offspring and on the reproductive effort, survival, and future fecundity of the mothers. Mean offspring body s…
Sequential analyses in coercive mother-child interaction: the predictability hypothesis in abusive versus nonabusive dyads.
1999
Abstract Objective: A two-fold purpose guided the present study: 1) To test the sequential relationship between the child’s aversive behavior and both the predictability and the compliance episodes, as well as the sequential relationship between these two mothering episodes proposed by the new predictability hypothesis (Wahler, Williams, & Cerezo, 1990) ; 2) to explore whether or not these patterns are specific to these dysfunctional dyads by using a nonabusive comparison group. Method: Fifty mother-child dyads, 25 abusive and 25 nonabusive, participated in this study. Lag sequential analyses were carried out on 302 hours of direct observation, 178 hours in the abusive group, and 124 in the…
Mothering under the influence: How perinatal drugs of abuse alter the mother-infant interaction
2018
AbstractAlthough drug-abusing women try to moderate their drug and alcohol use during pregnancy, they often relapse at a time when childcare needs are high and maternal bonding is critical to an infant’s development. In the clinical setting, the search for the neural basis of drug-induced caregiving deficits is complex due to several intervening variables. Rather, the preclinical studies that control for drug dose and regimen, as well as for gestational and postpartum environment, allow a precise determination of the effects of drugs on maternal behaviour. Given the relevance of the issue, this review will gather reports on the phenotypic correlates of maternal behaviour in preclinical stud…
Associations between infant and maternal characteristics measured at child age 5 months and maternal feeding styles and practices up to child age two…
2022
Facilitating positive feeding practices from infancy may be an important strategy to prevent childhood overweight and obesity. Since the feeding situation early in life constitutes a bidirectional relationship, it is important to understand the impact of both maternal and infant characteristics on maternal feeding practices to intervene in a customized and tailored way. Few studies have concurrently examined associations between maternal and infant characteristics in relation to early maternal feeding practices. The aim of the present study was to explore potential associations between infant and maternal characteristics measured at child age five months, and maternal feeding styles and pra…
Links between maternal feeding practices and children's eating difficulties. Validation of French tools
2012
Abstract: The main objectives of the study were to validate a measure of young children's eating difficulties and maternal feeding practices in a French sample, and to assess the links between these practices and children's eating difficulties. Mothers of French children aged 20-36 months completed 4 questionnaires that were validated using a Structural Equation Modelling approach. Links between children and maternal components were investigated using a PLS regression. The Children's Eating Difficulties Questionnaire yielded a 4-dimension solution: Neophobia, Pickiness, Low Appetite and Low Enjoyment in food. The Feeding Style Questionnaire assessed 3 dimensions: Authoritarian, Authoritativ…