scholarly journals Evolutionary implications of interspecific variation in a maternal effect: a meta-analysis of yolk testosterone response to competition

2016 ◽  
Vol 3 (11) ◽  
pp. 160499 ◽  
Author(s):  
Alexandra B. Bentz ◽  
Daniel J. Becker ◽  
Kristen J. Navara

Competition between conspecifics during the breeding season can result in behavioural and physiological programming of offspring via maternal effects. For birds, in which maternal effects are best studied, it has been claimed that exposure to increased competition causes greater deposition of testosterone into egg yolks, which creates faster growing, more aggressive offspring; such traits are thought to be beneficial for high-competition environments. Nevertheless, not all species show a positive relationship between competitive interactions and yolk testosterone, and an explanation for this interspecific variation is lacking. We here test if the magnitude and direction of maternal testosterone allocated to eggs in response to competition can be explained by life-history traits while accounting for phylogenetic relationships. We performed a meta-analysis relating effect size of yolk testosterone response to competition with species coloniality, nest type, parental effort and mating type. We found that effect size was moderated by coloniality and nest type; colonial species and those with open nests allocate less testosterone to eggs when in more competitive environments. Applying a life-history perspective helps contextualize studies showing little or negative responses of yolk testosterone to competition and improves our understanding of how variation in this maternal effect may have evolved.

2005 ◽  
Vol 86 (3) ◽  
pp. 161-170 ◽  
Author(s):  
ANE T. LAUGEN ◽  
LOESKE E. B. KRUUK ◽  
ANSSI LAURILA ◽  
KATJA RÄSÄNEN ◽  
JONATHAN STONE ◽  
...  

The degree to which genetic variation in a given trait varies among different populations of the same species and across different environments has seldom been quantified in wild vertebrate species. We investigated the expression of genetic variability and maternal effects in three larval life-history traits of the amphibian Rana temporaria. In a factorial laboratory experiment, five widely separated populations (max. 1600 km) were subjected to two different environmental treatments. Animal model analyses revealed that all traits were heritable (h2≈0·20) in all populations and under most treatment combinations. Although the cross-food treatment genetic correlations were close to unity, heritabilities under a restricted food regime tended to be lower than those under an ad libitum food regime. Likewise, maternal effects (m2≈0·05) were detected in most traits, and they tended to be most pronounced under restricted food conditions. We detected several cross-temperature genetic and maternal effects correlations that were lower than unity, suggesting that genotype–environment interactions and maternal effect–environment interactions are a significant source of phenotypic variation. The results reinforce the perspective that although the expression of genetic and maternal effects may be relatively homogeneous across different populations of the same species, local variation in environmental conditions can lead to significant variation in phenotypic expression of quantitative traits through genotype–environment and maternal effect–environment interactions.


2018 ◽  
Vol 49 (5) ◽  
pp. 303-309 ◽  
Author(s):  
Jedidiah Siev ◽  
Shelby E. Zuckerman ◽  
Joseph J. Siev

Abstract. In a widely publicized set of studies, participants who were primed to consider unethical events preferred cleansing products more than did those primed with ethical events ( Zhong & Liljenquist, 2006 ). This tendency to respond to moral threat with physical cleansing is known as the Macbeth Effect. Several subsequent efforts, however, did not replicate this relationship. The present manuscript reports the results of a meta-analysis of 15 studies testing this relationship. The weighted mean effect size was small across all studies (g = 0.17, 95% CI [0.04, 0.31]), and nonsignificant across studies conducted in independent laboratories (g = 0.07, 95% CI [−0.04, 0.19]). We conclude that there is little evidence for an overall Macbeth Effect; however, there may be a Macbeth Effect under certain conditions.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Hyune June Lee ◽  
Sung Min Kim ◽  
Ji Yean Kwon

Abstract Background Peripartum depression is a common disorder with very high potential hazards for both the patients and their babies. The typical treatment options include antidepressants and electroconvulsive therapy. However, these treatments do not ensure the safety of the fetus. Recently, repetitive transcranial magnetic stimulation has emerged as a promising treatment for neuropathies as well as depression. Nevertheless, many studies excluded pregnant women. This systematic review was conducted to confirm whether repetitive transcranial magnetic stimulation was a suitable treatment option for peripartum depression. Methods We performed a systematic review that followed the PRISMA guidelines. We searched for studies in the MEDLINE, PsycINFO, EMBASE, and Cochrane library databases published until the end of September 2020. Eleven studies were selected for the systematic review, and five studies were selected for quantitative synthesis. Data analysis was conducted using Comprehensive Meta-Analysis 3 software. The effect size was analyzed using the standardized mean difference, and the 95% confidence interval (CI) was determined by the generic inverse variance estimation method. Results The therapeutic effect size of repetitive transcranial magnetic stimulation for peripartum depression was 1.394 (95% CI: 0.944–1.843), and the sensitivity analysis effect size was 1.074 (95% CI: 0.689–1.459), indicating a significant effect. The side effect size of repetitive transcranial magnetic stimulation for peripartum depression was 0.346 (95% CI: 0.214–0.506), a meaningful result. There were no severe side effects to the mothers or fetuses. Conclusions From various perspectives, repetitive transcranial magnetic stimulation can be considered an alternative treatment to treat peripartum depression to avoid exposure of fetuses to drugs and the severe side effects of electroconvulsive therapy. Further research is required to increase confidence in the results.


2021 ◽  
pp. 152483802110216
Author(s):  
Brooke N. Lombardi ◽  
Todd M. Jensen ◽  
Anna B. Parisi ◽  
Melissa Jenkins ◽  
Sarah E. Bledsoe

Background: The association between a lifetime history of sexual victimization and the well-being of women during the perinatal period has received increasing attention. However, research investigating this relationship has yet to be systematically reviewed or quantitatively synthesized. Aim: This systematic review and meta-analysis aims to calculate the pooled effect size estimate of the statistical association between a lifetime history of sexual victimization and perinatal depression (PND). Method: Four bibliographic databases were systematically searched, and reference harvesting was conducted to identify peer-reviewed articles that empirically examined associations between a lifetime history of sexual victimization and PND. A random effects model was used to ascertain an overall pooled effect size estimate in the form of an odds ratio and corresponding 95% confidence intervals (CIs). Subgroup analyses were also conducted to assess whether particular study features and sample characteristic (e.g., race and ethnicity) influenced the magnitude of effect size estimates. Results: This review included 36 studies, with 45 effect size estimates available for meta-analysis. Women with a lifetime history of sexual victimization had 51% greater odds of experiencing PND relative to women with no history of sexual victimization ( OR = 1.51, 95% CI [1.35, 1.67]). Effect size estimates varied considerably according to the PND instrument used in each study and the racial/ethnic composition of each sample. Conclusion: Findings provide compelling evidence for an association between a lifetime history of sexual victimization and PND. Future research should focus on screening practices and interventions that identify and support survivors of sexual victimization perinatally.


2021 ◽  
pp. 1-33
Author(s):  
Chantal VAN DIJK ◽  
Elise VAN WONDEREN ◽  
Elly KOUTAMANIS ◽  
Gerrit Jan KOOTSTRA ◽  
Ton DIJKSTRA ◽  
...  

Abstract Although cross-linguistic influence at the level of morphosyntax is one of the most intensively studied topics in child bilingualism, the circumstances under which it occurs remain unclear. In this meta-analysis, we measured the effect size of cross-linguistic influence and systematically assessed its predictors in 750 simultaneous and early sequential bilingual children in 17 unique language combinations across 26 experimental studies. We found a significant small to moderate average effect size of cross-linguistic influence, indicating that cross-linguistic influence is part and parcel of bilingual development. Language dominance, operationalized as societal language, was a significant predictor of cross-linguistic influence, whereas surface overlap, language domain and age were not. Perhaps an even more important finding was that definitions and operationalisations of cross-linguistic influence and its predictors varied considerably between studies. This could explain the absence of a comprehensive theory in the field. To solve this issue, we argue for a more uniform method of studying cross-linguistic influence.


2020 ◽  
Author(s):  
Kyung Hee Lee ◽  
Ji Yeon Lee ◽  
Bora Kim

Abstract Background and Objectives The concept of person-centered care has been utilized/adapted to various interventions to enhance health-related outcomes and ensure the quality of care delivered to persons living with dementia. A few systematic reviews have been conducted on the use of person-centered interventions in the context of dementia care, but to date, none have analyzed intervention effect by intervention type and target outcome. This study aimed to review person-centered interventions used in the context of dementia care and examine their effectiveness. Research Design and Methods A systematic review and meta-analysis were conducted. We searched through five databases for randomized controlled trials that utilized person-centered interventions in persons living with dementia from 1998 to 2019. Study quality was assessed using the National Institute for Health and Clinical Excellence. The outcomes of interest for the meta-analysis were behavioral and psychological symptoms in dementia (BPSD) and cognitive function assessed immediately after the baseline measurement. Results In total, 36 studies were systematically reviewed. Intervention types were: reminiscence, music, and cognitive therapies, and multisensory stimulation. Thirty studies were included in the meta-analysis. Results showed a moderate effect size for overall intervention, a small one for music therapy, and a moderate one for reminiscence therapy on BPSD and cognitive function. Discussion and Implications Generally speaking, person-centered interventions showed immediate intervention effects on reducing BPSD and improving cognitive function, although the effect size and significance of each outcome differed by intervention type. Thus, healthcare providers should consider person-centered interventions as a vital element in dementia care.


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