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 …
Advantage of rare infanticide strategies in an invasion experiment of behavioural polymorphism
2012
Killing conspecific infants (infanticide) is among the most puzzling phenomena in nature. Stable polymorphism in such behaviour could be maintained by negative frequency-dependent selection (benefit of rare types). However, it is currently unknown whether there is genetic polymorphism in infanticidal behaviour or whether infanticide may have any fitness advantages when rare. Here we show genetic polymorphism in non-parental infanticide. Our novel invasion experiment confirms negative frequency-dependent selection in wild bank vole populations, where resource benefits allow an infanticidal strategy to invade a population of non-infanticidal individuals. The results show that infanticidal beh…
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.
Short-term benefits, but transgenerational costs of maternal loss in an insect with facultative maternal care
2015
A lack of parental care is generally assumed to entail substantial fitness costs for offspring that ultimately select for the maintenance of family life across generations. However, it is unknown whether these costs arise when parental care is facultative, thus questioning their fundamental importance in the early evolution of family life. Here, we investigated the short-term, long-term and transgenerational effects of maternal loss in the European earwig Forficula auricularia , an insect with facultative post-hatching maternal care. We showed that maternal loss did not influence the developmental time and survival rate of juveniles, but surprisingly yielded adults of larger body and force…
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…
Socio-Reproductive Conflicts and the Father’s Curse Dilemma
2018
Evolutionary conflicts between males and females can manifest over sexually antagonistic interactions at loci or over sexually antagonistic interests within a locus. The latter form of conflict, intralocus sexual conflict, arises from sexually antagonistic selection and constrains the fitness of individuals through a phenotypic compromise. These conflicts, and socio-reproductive interactions in general, are commonly mediated by hormones, and thus predictive insights can be gained from studying their mediating effects. Here, we integrate several lines of evidence to describe a novel, hormonally mediated reproductive dilemma that we call the father’s curse, which results from an intralocus co…
Impact of Low Maternal Education on Early Childhood Overweight and Obesity in Europe
2016
BackgroundComparable evidence on adiposity inequalities in early life is lacking across a range of European countries. This study investigates whether low maternal education is associated with overweight and obesity risk in children from distinct European settings during early childhood. MethodsProspective data of 45 413 children from 11 European cohorts were used. Children's height and weight obtained at ages 4-7 years were used to assess prevalent overweight and obesity according to the International Obesity Task Force definition. The Relative/Slope Indices of Inequality (RII/SII) were estimated within each cohort and by gender to investigate adiposity risk among children born to mothers …
Effects of a short video feedback intervention on enhancing maternal sensitivity and infant development in low-income families
2019
This study evaluated the effects of a short video feedback intervention aimed at enhancing maternal sensitivity and the development of infants from low-income families in a randomized controlled trial. Forty-four mother-infant dyads living in low-income communities from Salvador, Brazil were randomly assigned between intervention and control groups. Maternal sensitivity was assessed during free-play and infant development was evaluated with a standardized scale. Intervention took place in eight home visits between the infant's third and tenth month. Results showed mothers in the intervention group interpreted the meaning of their infants' behavior more often (r = 0.33), asked babies more qu…
Maternal anxiety following delivery, early infant temperament and mother's confidence in caregiving.
2015
AbstractA mother’s emotional state is a well-known environmental factor that relates to the development of infant temperament. However, some relevant issues have not yet been fully explored. The current study examines the influence of determined maternal, contextual and perinatal variables on infant temperament and the mother’s confidence in caregiving during the first weeks of life. A prospective study was carried out in three-hundred and seventeen newborns and their mothers. Perinatal and socio-demographic variables were recorded. The mother’s anxiety and mood were measured in the first days after childbirth and again at 8 weeks. Infant temperament and the mother’s confidence in caregivin…
Mother-infant interaction and children's socio-emotional development with high- and low-risk mothers.
2008
Charting the dynamic character of mother-infant interaction requires using observational systems of sequential coding in real time. A longitudinal study was designed to approach maternal sensitivity in a more complex way using sequential analysis. The study was conducted with 20 high- and 20 low-risk mothers and their infants (aged: 3, 12 and 15 months) to examine the relation among mothers' risk status for physical abuse and their maternal interactive profiles, using micro-social sequential analyses, and the subsequent quality of attachment developed by their children at 15 months of age. Results showed significantly different timings in maternal responses in high- and low-risk groups, tha…