Boring life: early colony formation and growth in the endolithic bryozoan genus Penetrantia Silén, 1946.

As in most colonial and sessile marine invertebrates, bryozoan life history is characterized by asexual propagation of zooids for colonial growth and by sexual production of larvae for dispersal. However, comprehensive life histories, particularly in cryptic species such as endolithic (boring) bryozoans, remain poorly understood. The ctenostome family Penetrantiidae is widespread from temperate to tropical waters and often found in molluscan shells, offering an opportunity to study the boring lifestyle and its potential impact on bioerosion through growth and settlement experiments. Our research focused on Penetrantia clionoides from Guam in the Pacific Ocean, Penetrantia japonica from Japan, and a Penetrantia species from France in the Atlantic Ocean. We found distinct life histories and reproductive patterns potentially influenced by environmental factors such as temperature and food availability. The tropical P. clionoides displayed higher rates of larval production and growth compared to its temperate counterpart. For instance, the mean stolon extension was 335.2 µm/week in P. clionoides versus 232.1 µm/week in Penetrantia sp. Autozooid development took 13 days in P. clionoides and 31 days in Penetrantia sp. Anatomical features like apertural rims aided in species identification and in understanding larval settlement preferences, suggesting a tendency for philopatric settlement behavior. The bioerosional impact of penetrantiids remains little understood, but we generated first projections of bioerosion rates and a protocol for keeping Penetrantia under laboratory conditions, laying a foundation for further research in this field.

What is high rumination?

OBJECTIVE: The current paper tries to illuminate the need for standard cutoff points. INTRODUCTION: rumination is considered to be a transdiagnostic process leading to a variety of consequences. But, what is prominent ruminative tendency? Are there agreed-upon specifications or cutoff points that distinguish between high and low tendency to ruminate? In an attempt to answer these questions, we reviewed 25 works that compared people characterized as high or low in rumination. We found numerous inconsistencies in the characterization criteria and a great variability in cutoff points. Most studies did not provide enough information about the cutoff criteria or values. METHOD: We examined a sample of 454 participants using the RRS (Ruminative Response Scale), from which we tried to identify standard cutoff points. RESULTS SHOWED: 1) distributions of RRS, brooding and reflective pondering; 2) most studies used median split, which might explain the differences among studies; 3) examination of standard scores for the various cutoffs presented big variability among the studies; and 4) women had higher scores of rumination and brooding than men. CONCLUSION: Our paper highlights the need for homogeneity in the field. It suggests addressing the RRS, brooding and reflective pondering distributions as references for future studies. We recommend specifying: cutoff criteria, cutoff values, range, means and standard deviations. Researchers should consider the specific population (i.e., men vs. women or clinical vs. non clinical) of interest and infer specific cutoff points accordingly. Importantly, researchers should consider the implications of their choice of cutoff points and apply their criterion accordingly.

Functional brain network dynamics of brooding in depression: insights from real-time fMRI neurofeedback.

Background: Brooding is a critical symptom and prognostic factor of major depressive disorder (MDD), which involves passively dwelling on self-referential dysphoria and related abstractions. The neurobiology of brooding remains under characterized. We aimed to elucidate neural dynamics underlying brooding, and explore their responses to neurofeedback intervention in MDD. Methods: We investigated functional MRI (fMRI) dynamic functional network connectivity (dFNC) in 36 MDD subjects and 26 healthy controls (HCs) during rest and brooding. Rest was measured before and after fMRI neurofeedback (MDD-active/sham: n=18/18, HC-active/sham: n=13/13). Baseline brooding severity was recorded using Ruminative Response Scale - Brooding subscale (RRS-B). Results: Four recurrent dFNC states were identified. Measures of time spent were not significantly different between MDD and HC for any of these states during brooding or rest. RRS-B scores in MDD showed significant negative correlation with measures of time spent in dFNC state 3 during brooding (r=-0.5, p= 1.7E-3, FDR-significant). This state comprises strong connections spanning several brain systems involved in sensory, attentional and cognitive processing. Time spent in this anti-brooding dFNC state significantly increased following neurofeedback only in the MDD active group (z=-2.09, p=0.037). Limitations: The sample size was small and imbalanced between groups. Brooding condition was not examined post-neurofeedback. Conclusion: We identified a densely connected anti-brooding dFNC brain state in MDD. MDD subjects spent significantly longer time in this state after active neurofeedback intervention, highlighting neurofeedback's potential for modulating dysfunctional brain dynamics to treat MDD.

Perinatal posttraumatic stress disorder as a predictor of mother-child bonding quality 8 months after childbirth: a longitudinal study.

BACKGROUND: Negative childbirth experiences can be related to the onset of perinatal post-traumatic stress symptomatology (P-PTSS), which significantly impacts the mother and the infant. As a response in the face of the discomfort caused by P-PTSS, maladaptive emotion regulation strategies such as brooding can emerge, contributing to the consolidation of post-partum depressive symptoms. Ultimately, both types of symptomatology, P-PTSS and post-partum depression, can act as risk factors for developing mother-child bonding difficulties. Still, this full set of temporal paths has to date remained untested. The present longitudinal study aimed to analyze the risk factors associated with the appearance of P-PTSS after post-partum and to test a path model considering the role of P-PTSS as an indirect predictor of bonding difficulties at eight months of postpartum. METHODS: An initial sample of pregnant women in the third trimester of gestation (N = 594) participated in a longitudinal study comprising two follow-ups at two and eight months of postpartum. The mothers completed online evaluations that included socio-demographic data and measures of psychological variables. A two-step linear regression model was performed to assess the predictive role of the variables proposed as risk factors for P-PTSS, and a path model was formulated to test the pathways of influence of P-PTSS on bonding difficulties. RESULTS: A history of psychopathology of the mother, the presence of depression during pregnancy, the presence of medical complications in the mother, and the occurrence of traumatic birth experiences all acted as significant predictors of P-PTSS, explaining 29.5% of its variance. Furthermore, the path model tested further confirmed an indirect effect of P-PTSS, triggered by a negative childbirth experience, on subsequent bonding difficulties eight months after labor through its association with higher levels of brooding and, ultimately, postpartum depression levels. A further path showed that bonding difficulties at two months postpartum can persist at eight months postpartum due to the onset of brooding and postpartum depression symptoms. CONCLUSION: We identified a set of robust predictors of P-PTSS: the mother's previous history of depression, perinatal depression during pregnancy, the presence of medical complications in the mother and the occurrence of traumatic birth experiences, which has important implications for prevention. This is particularly relevant, as P-PTSS, when triggered by a negative childbirth experience, further indirectly predicted the development of mother-child bonding difficulties through the mediation of higher use of brooding and symptoms of postpartum depression. These findings can serve as a basis for developing new longitudinal studies to further advance the understanding of perinatal mechanisms of mental health.

Cognitive Vulnerability to Mood Deterioration in an Exercise Cessation Paradigm.

Mood deterioration in response to exercise cessation is well-documented, but moderators of this effect remain unknown. This study tested the hypothesis that physically active individuals with higher levels of cognitive vulnerability (i.e., tendencies towards negative thought content and processes in response to stress or negative mood states) are at greater risk for increased anxiety and depressive symptoms when undergoing exercise cessation. Community adults meeting recommended physical activity guidelines (N=36) participated in a 4-week prospective, longitudinal study with 2 weeks each of maintained exercise and exercise cessation. Cognitive vulnerability measures included dysfunctional attitudes, brooding rumination, and cognitive reactivity (i.e., change in dysfunctional attitudes over a dysphoric mood induction). Anxiety and depression symptoms increased during exercise cessation. Brooding emerged as a risk factor for increases in Tension scores on the Profile of Mood States-Brief during exercise cessation. Future studies should explore brooding as a mediator (i.e., potential mechanism) of exercise-induced mood deterioration.

May brood desertion be ruled by partner parenting capability in a polygamous songbird? An experimental study.

Parents confront multiple aspects of offspring demands and need to coordinate different parental care tasks. Biparental care is considered to evolve under circumstances where one parent is not competent for all tasks and cannot efficiently raise offspring. However, this hypothesis is difficult to test, as uniparental and biparental care rarely coexist. Chinese penduline tits (Remiz consobrinus) provide such a system where both parental care types occur. Here, we experimentally investigated whether parents in biparental nests are less capable of caring than parents in uniparental nests. We monitored parenting efforts at (1) naturally uniparental and biparental nests and (2) biparental nests before and during the temporary removal of a parent. Given the relatively small sample sizes, we have employed various statistical analyses confirming the robustness of our results. We found that total feeding frequency and brooding duration were similar for natural uniparental and biparental nests. Feeding frequency, but not brooding duration, contributed significantly to nestling mass. In line with this, a temporary parental removal revealed that the remaining parents at biparental nests fully compensated for the partner's feeding absence but not for brooding duration. This reflects that the manipulated parents are confronted with a trade-off between feeding and brooding and were selected to invest in the more influential one. However, such a trade-off may not occur in parents of natural uniparental care nests. The different capabilities of a parent independently coordinating feeding and brooding tasks suggest that parents from biparental and uniparental nests were exposed to different resource conditions, thereby foraging efficiency may differ between care types.

Unpacking affect maintenance and its association with depressive symptoms: integrating positive and negative affects.

ABSTRACTDepression is associated with increased maintenance of negative affect (NA) and reduced - blunted and short-lived - maintenance of positive affect (PA). Studies have focused on factors associated with the maintenance of NA, specifically, the emotion regulation strategy of brooding and the capacity to hold negative affective experiences in working memory (WM). Despite its theoretical importance, less attention has been given to factors associated with the maintenance of PA in depression. This study aims to synthesise factors playing a role in the maintenance of both NA and PA. Specifically, we used self-reported assessment of PA and NA regulation and performance-based measures of NA and PA processing in WM to predict depressive symptoms severity. Participants (N = 219) completed the Affective Maintenance Task (AMT, Mikels et al., 2008), which provided performance-based measures of PA and NA maintenance, and filled out questionnaires assessing brooding, positive rumination and depressive severity. Brooding, positive rumination and AMT-based measures of positive (but not negative) affective information processing were independently associated with depressive symptoms. We highlight the unique contributions of PA processing, as well as of self-reported emotion regulation strategies in understanding depression maintenance.

Rumination and Gender in the Relation Between Perceived Threat and State Anxiety During COVID-19.

OBJECTIVES: Perception of and subsequent responses to counter threats by disease, such as COVID-19, are essential for engagement in self-protective behaviors. But, associated increases in anxiety that accompany the threat of disease may negatively impact well-being. Therefore, identifying variables that may modulate the association between perceived threat from COVID-19 and anxiety is important. We conducted a study to examine the moderating roles of two subtypes of rumination (brooding and reflection) in the association between perceived threat from COVID-19 and state anxiety. Additionally, as both COVID-19 outcomes and the tendency to ruminate differ across genders, we explored gender as a second moderator. METHODS: Participants (N = 300; Men = 144) were recruited online in April 2020 and completed measures of state anxiety, brooding and reflective rumination, and perceived threat from COVID-19. RESULTS: Moderation regression analyses revealed that perceived threat and brooding were independently associated with increased state anxiety. Reflective rumination and gender, however, significantly moderated the relation between perceived threat and state anxiety. For men, reflective rumination strengthened the association between threat and anxiety. For women, reflective rumination weakened this association; women with the highest scores in reflective rumination also reported high state anxiety at low, medium, and high perceived threat levels. CONCLUSIONS: These findings illuminate gender differences in the relations between perceived threat, rumination, and experienced state anxiety during the pandemic.

Effects of a Digital Mental Health Intervention on Perceived Stress and Rumination in Adolescents Aged 13 to 17 Years: Randomized Controlled Trial.

BACKGROUND: Although adolescents report high levels of stress, they report engaging in few stress management techniques. Consequently, developing effective and targeted programs to help address this transdiagnostic risk factor in adolescence is particularly important. Most stress management programs for adolescents are delivered within schools, and the evidence for these programs is mixed, suggesting a need for alternative options for stress management among adolescents. OBJECTIVE: The aim of the study is to test the short-term effects of a self-guided digital mental health intervention (DMHI) designed for adolescents on perceived stress and rumination (ie, brooding). METHODS: This was a 12-week, 2-arm decentralized randomized controlled trial of adolescents aged 13 to 17 years who presented with elevated levels of perceived stress and brooding. Participants were randomly assigned to engage with a self-guided DMHI (Happify for Teens) or to a waitlist control. Participants assigned to the intervention group were given access to the program for 12 weeks. Happify for Teens consists of various evidence-based activities drawn from therapeutic modalities such as cognitive behavioral therapy, positive psychology, and mindfulness, which are then organized into several programs targeting specific areas of concern (eg, Stress Buster 101). Participants in the waitlist control received access to this product for 12 weeks upon completing the study. Participants in both groups completed measures of perceived stress, brooding, optimism, sleep disturbance, and loneliness at baseline, 4 weeks, 8 weeks, and 12 weeks. Changes in outcomes between the intervention and waitlist control groups were assessed using repeated-measures multilevel models. RESULTS: Of the 303 participants included in data analyses, 132 were assigned to the intervention and 171 to the waitlist. There were significantly greater improvements in the intervention condition for perceived stress (intervention: B=-1.50; 95% CI -1.82 to -1.19; P<.001 and control: B=-0.09; 95% CI -0.44 to 0.26; P=.61), brooding (intervention: B=-0.84; 95% CI -1.00 to -0.68; P<.001 and control: B=-0.30; 95% CI -0.47 to -0.12; P=.001), and loneliness (intervention: B=-0.96; 95% CI -1.2 to -0.73; P<.001 and control: B=-0.38; 95% CI: -0.64 to -0.12; P=.005) over the 12-week study period. Changes in optimism and sleep disturbance were not significantly different across groups (Ps≥.096). CONCLUSIONS: Happify for Teens was effective at reducing perceived stress, rumination, and loneliness among adolescents over 12 weeks when compared to a waitlist control group. Our data reveal the potential benefits of DMHIs for adolescents, which may present a more scalable, destigmatized, and cost-effective alternative to school-based programs. TRIAL REGISTRATION: ClinicalTrials.gov NCT04567888; https://clinicaltrials.gov/ct2/show/NCT04567888. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/25545.

Hard to let it go: repetitive negative thinking and hoarding in later life in Japan.

Objectives: Hoarding in older adults can have a detrimental effect on daily life. Repetitive negative thinking (RNT) could result in a greater avoidance of discarding and increased saving behaviors; yet, the unique role of RNT on hoarding in older adults remains understudied. This study aimed to investigate whether the intensity of RNT contributes to hoarding in older adults. Methods: Two hundred and sixty-four older adults in Japan (ages 65-86 years, 132 males and 132 females) participated in an online survey. Hierarchical regression analyses were conducted to examine whether RNT could significantly explain the variance of hoarding after controlling for age, sex, years of education, self-reported cognitive impairment, and depression. Results: As we expected, RNT was significantly associated with greater hoarding behaviors, such as excessive acquisition (ß = .27, p = .005) and difficulty in discarding (ß = .27, p = .003). On the other hand, reflection, repetitive thinking without negative emotional valence, was significantly associated with higher scores on clutter (ß = .36 p < .001). Conclusion: Our findings highlight the importance of addressing RNT in the prevention and treatment of hoarding symptoms among older adults, potentially leading to more effective interventions and improved outcomes in managing hoarding behaviors in this population.

Depression and bedtime procrastination: Chain mediation of brooding and perceived stress.

This study aimed to investigate the relationships between depression and bedtime procrastination (BP), and the mediating effect of the brooding and perceived stress (PS). Based on the self-regulatory failure theory of procrastination in a temporal context and response styles theory, we constructed a chain mediation model. Total of 1136 participants (389 males and 747 females) completed the online questionnaire. In the present study, the participants were asked to fill The Beck Depression Inventory-II (BDI-II), Bedtime Procrastination Scale (BPS), Perceived Stress Scale (PSS) and Ruminative Responses Scale (RRS). The results showed that high level of depression positively affected brooding, and high level of brooding further positively affected PS, thus leading to BP. However, we did not find the mediating effect of brooding between depression and BP. This indicated that mood plays an important role in the mechanism of depression's effect on BP. The findings revealed pathways between depression and BP and was of great significance for the intervention of BP.

Prospective Relation between Ruminative Subtypes and Suicide Ideation: Moderating Role of Problem Solving.

Background: Although reflection has been characterized as a more adaptive subtype of rumination than brooding, evidence suggests that reflection is associated with suicide ideation. The present longitudinal study investigated the mediating role of hopelessness and depressive symptoms and the moderating role of problem solving in explaining why reflection may lead to suicide ideation. Methods: Two hundred ninety-four undergraduates participated in the study and were followed up every 6 months over 18 months. Participants completed measures of brooding and reflection, hopelessness, depressive symptoms, problem solving, and suicide ideation. Results: Results revealed that after adjusting for baseline suicide ideation, the serial mediation path from brooding (but not reflection) to suicide ideation via hopelessness and depressive symptoms was significant. Baseline reflection predicted suicide ideation 18 months later through depressive symptoms at 12 months for people average in passive problem solving, and for those low or average in active problem solving. Brooding predicted suicide ideation through depressive symptoms, regardless of problem-solving. Conclusions: Reflection may result in suicide ideation via depressive symptoms among people with poor problem-solving skills. Clinical and theoretical implications are discussed.

Multiple evolutionary transitions of reproductive strategies in a phylum of aquatic colonial invertebrates.

Parental care is considered crucial for the enhanced survival of offspring and evolutionary success of many metazoan groups. Most bryozoans incubate their young in brood chambers or intracoelomically. Based on the drastic morphological differences in incubation chambers across members of the order Cheilostomatida (class Gymnolaemata), multiple origins of incubation were predicted in this group. This hypothesis was tested by constructing a molecular phylogeny based on mitogenome data and nuclear rRNA genes 18S and 28S with the most complete sampling of taxa with various incubation devices to date. Ancestral character estimation suggested that distinct types of brood chambers evolved at least 10 times in Cheilostomatida. In Eucratea loricata and Aetea spp. brooding evolved unambiguously from a zygote-spawning ancestral state, as it probably did in Tendra zostericola, Neocheilostomata, and 'Carbasea' indivisa. In two further instances, brooders with different incubation chamber types, skeletal and non-skeletal, formed clades (Scruparia spp., Leiosalpinx australis) and (Catenicula corbulifera (Steginoporella spp. (Labioporella spp., Thalamoporella californica))), each also probably evolved from a zygote-spawning ancestral state. The modular nature of bryozoans probably contributed to the evolution of such a diverse array of embryonic incubation chambers, which included complex constructions made of polymorphic heterozooids, and maternal zooidal invaginations and outgrowths.

A landmark-free analysis of the pelvic girdle in Sulawesi ricefishes (Adrianichthyidae): How 2D and 3D geometric morphometrics can complement each other in the analysis of a complex structure.

Geometric morphometrics (GM) enable the quantification of morphological variation on various scales. Recent technical advances allow analyzing complex three-dimensional shapes also in cases where landmark-based approaches are not appropriate. Pelvic girdle bones (basipterygia) of Sulawesi ricefishes are 3D structures that challenge traditional morphometrics. We hypothesize that the pelvic girdle of ricefishes experienced sex-biased selection pressures in species where females provide brood care by carrying fertilized eggs supported by elongated pelvic fins ("pelvic brooding"). We test this by comparing pelvic bone shapes of both sexes in species exhibiting pelvic brooding and the more common reproductive strategy "transfer brooding," by using landmark-free 2D and 3D GM, as well as qualitative shape descriptions. Both landmark-free approaches revealed significant interspecific pelvic bone variation in the lateral process, medial facing side of the pelvic bone, and overall external and internal wing shape. Within pelvic brooders, the three analyzed species are clearly distinct, while pelvic bones of the genus Adrianichthys are more similar to transfer brooding Oryzias. Female pelvic brooding Oryzias exhibit prominent, medially pointing tips extending from the internal wing and basipterygial plate that are reduced or absent in conspecific males, Adrianichthys and transfer brooding Oryzias, supporting our hypothesis that selection pressures affecting pelvic girdle shape are sex-biased in Sulawesi ricefishes. Furthermore, both sexes of pelvic brooding Oryzias have overall larger pelvic bones than other investigated ricefishes. Based on these differences, we characterized two reproductive strategy- and sex-dependent pelvic girdle types for Sulawesi ricefishes. Morphological differences between the investigated pelvic brooding genera Adrianichthys and Oryzias provide additional evidence for two independent origins of pelvic brooding. Overall, our findings add to a better understanding on traits related to pelvic brooding in ricefishes and provide a basis for upcoming studies on pelvic girdle function and morphology.

Associations between daily affective experiences, trait and daily rumination on negative and positive affect: a diary study.

BACKGROUND: Rumination has mostly been studied in relation to depression, however, it may also occur in response to positive emotions (i.e., positive rumination) and therefore may be a protective factor related to the maintenance of positive mood. OBJECTIVE: We hypothesized that daily positive and negative affect would be associated with daily positive and negative rumination even after controlling for trait-level rumination. METHOD: We carried out a diary study with university students (n = 178), where participants had to answer short surveys online about their daily affect and daily rumination every evening for 10 days. We analyzed our data with multilevel regression in R. RESULTS: Daily positive and negative affect were significantly associated with daily negative and positive rumination, while trait-level rumination scores were not. Daily and trait-level rumination were moderately correlated (r = 0.333-0.440). CONCLUSIONS: Our findings highlight that daily rumination plays a more significant role in daily emotional experiences than trait rumination across positive and negative valence domains. Daily negative affect appears to be more closely related to higher daily negative rumination than the lack of daily positive rumination, which could be relevant for intervention strategies.

Patterns of life stress and the development of ruminative brooding in adolescence: A person-centered approach.

Research links life stressors, including acute, chronic, and early life stress, to the development of ruminative brooding. However, singular forms of life stress rarely occur in isolation, as adolescents typically encounter stressors that vary on important dimensions (e.g., types, timings, quantities) across development. The current study employs latent profile analysis (LPA) to identify natural clusters of life stress that, over time, may be differently associated with ruminative brooding. Evaluations of episodic, chronic, and early life stress were conducted with community-recruited mid-adolescents (N = 241, Mage = 15.90 years, 53% female) and their parents using the UCLA Life Stress Interview and lifetime adversity portions of the Youth Life Stress Interview. Analyses identified four distinct patterns: low stress, high peer stress, moderate home / family stress, and multifaceted / high school stress. Adolescents in the high peer stress and moderate home / family stress profiles were at highest risk for developing a brooding style over time. Despite high overall levels of stress, teens in the multifaceted / high school stress profile were at not at elevated risk for developing a brooding style. Findings demonstrate the utility of person-centered approaches to identify patterns of stress exposure that heighten risk for brooding over time.

Phosphoproteome Reveals Extracellular Regulated Protein Kinase Phosphorylation Mediated by Mitogen-Activated Protein Kinase Kinase-Regulating Granulosa Cell Apoptosis in Broody Geese.

Geese have strong brooding abilities, which severely affect their egg-laying performance. Phosphorylation is widely involved in regulating reproductive activities, but its role in goose brooding behavior is unclear. In this study, we investigated differences in the phosphoprotein composition of ovarian tissue between laying and brooding geese. Brooding geese exhibited ovarian and follicular atrophy, as well as significant oxidative stress and granulosa cell apoptosis. We identified 578 highly phosphorylated proteins and 281 lowly phosphorylated proteins, and a KEGG pathway analysis showed that these differentially phosphorylated proteins were mainly involved in cell apoptosis, adhesion junctions, and other signaling pathways related to goose brooding behavior. The extracellular regulated protein kinase (ERK)-B-Cell Lymphoma 2(BCL2) signaling pathway was identified as playing an important role in regulating cell apoptosis. The phosphorylation levels of ERK proteins were significantly lower in brooding geese than in laying geese, and the expression of mitogen-activated protein kinase kinase (MEK) was downregulated. Overexpression of MEK led to a significant increase in ERK phosphorylation and BCL2 transcription in H2O2-induced granulosa cells (p < 0.05), partially rescuing cell death. Conversely, granulosa cells receiving MEK siRNA exhibited the opposite trend. In conclusion, geese experience significant oxidative stress and granulosa cell apoptosis during brooding, with downregulated MEK expression, decreased phosphorylation of ERK protein, and inhibited expression of BCL2.

Effects of heat waves on telomere dynamics and parental brooding effort in nestlings of the zebra finch (Taeniopygia castanotis) transitioning from ectothermy to endothermy.

Heat waves are predicted to be detrimental for organismal physiology with costs for survival that could be reflected in markers of biological state such as telomeres. Changes in early life telomere dynamics driven by thermal stress are of particular interest during the early post-natal stages of altricial birds because nestlings quickly shift from being ectothermic to endothermic after hatching. Telomeres of ectothermic and endothermic organisms respond differently to environmental temperature, but few investigations within species that transition from ectothermy to endothermy are available. Also, ambient temperature influences parental brooding behaviour, which will alter the temperature experienced by offspring and thereby, potentially, their telomeres. We exposed zebra finch nestlings to experimental heat waves and compared their telomere dynamics to that of a control group at 5, 12 and 80 days of age that encapsulate the transition from the ectothermic to the endothermic thermoregulatory stage; we also recorded parental brooding, offspring sex, mass, growth rates, brood size and hatch order. Nestling mass showed an inverse relationship with telomere length, and nestlings exposed to heat waves showed lower telomere attrition during their first 12 days of life (ectothermic stage) compared to controls. Additionally, parents of heated broods reduced the time they spent brooding offspring (at 5 days old) compared to controls. Our results indicate that the effect of heat waves on telomere dynamics likely varies depending on age and thermoregulatory stage of the offspring in combination with parental brooding behaviour during growth.

Crying over spilled milk? A network analysis of aversive well-being comparison, brooding rumination and depressive symptoms.

BACKGROUND: Comparative thinking about one's well-being is ubiquitous. Comparisons that threaten an individual's self-motives are aversive and interact with rumination and depression. Aversive well-being comparisons include upward social, past temporal, counterfactual, and criteria-based comparisons, as well as downward prospective temporal comparisons. Although the frequency, discrepancy, and affective impact of aversive comparison total scores have been associated with brooding rumination and depression, no study has investigated the interaction of specific comparison standards (e.g., social or counterfactual) with symptom cascades of brooding and depressive symptoms. METHODS: To examine this interaction, we conducted network analyses on the interplay between aversive well-being comparisons, brooding rumination, and depression. Specifically, we conducted a cross-sectional study in N = 500 dysphoric individuals and a longitudinal study in N = 921 participants at two timepoints, three months apart. Participants completed measures of depression, brooding, and the Comparison Standards Scale for Well-being, which assessed the frequency, perceived discrepancy, and affective impact of aversive well-being comparisons. RESULTS: Feelings of worthlessness emerged as the most central attribute in the networks of the dysphoric sample. Longitudinally, brooding and depressive symptoms predicted aversive comparisons, but not the other way around, which accounted for social and other-referent counterfactual comparisons to a greater degree than for other comparison types. LIMITATIONS: We used nonclinical samples. CONCLUSIONS: The findings highlight the critical role of comparison standards in depression. Further research is warranted to detect potential intervention targets for mitigating negative effects of negative self-evaluation.

Potential Contribution of Ancient Introgression to the Evolution of a Derived Reproductive Strategy in Ricefishes.

Transitions from no parental care to extensive care are costly and involve major changes in life history, behavior, and morphology. Nevertheless, in Sulawesi ricefishes, pelvic brooding evolved from transfer brooding in two distantly related lineages within the genera Adrianichthys and Oryzias, respectively. Females of pelvic brooding species carry their eggs attached to their belly until the fry hatches. Despite their phylogenetic distance, both pelvic brooding lineages share a set of external morphological traits. A recent study found no direct gene flow between pelvic brooding lineages, suggesting independent evolution of the derived reproductive strategy. Convergent evolution can, however, also rely on repeated sorting of preexisting variation of an admixed ancestral population, especially when subjected to similar external selection pressures. We thus used a multispecies coalescent model and D-statistics to identify gene-tree-species-tree incongruencies, to evaluate the evolution of pelvic brooding with respect to interspecific gene flow not only between pelvic brooding lineages but also between pelvic brooding lineages and other Sulawesi ricefish lineages. We found a general network-like evolution in Sulawesi ricefishes, and as previously reported, we detected no gene flow between the pelvic brooding lineages. Instead, we found hybridization between the ancestor of pelvic brooding Oryzias and the common ancestor of the Oryzias species from the Lake Poso area. We further detected signs of introgression within the confidence interval of a quantitative trait locus associated with pelvic brooding in O. eversi. Our results hint toward a contribution of ancient standing genetic variation to the evolution of pelvic brooding in Oryzias.