Methods: 191 middle-aged adults from a community-based study on resilience were asked to complete 30 daily diaries assessing positive and negative affect. At least 6 months later, participants completed a phone interview that assessed distress (i.e., depressive and anxiety symptoms), well-being (i.e., WHO-5 well-being, vitality, social functioning), physical functioning, and perceived stress.
Results: A three-factor solution with latent factors representing overall, negative, and positive EC was identified. Overall EC significantly predicted enhanced physical functioning, but was not associated with distress or well-being. Contrary to study hypotheses, positive and negative EC were not associated with future distress, well-being, or physical functioning, though a trend toward improved physical functioning was noted for positive EC. In contrast, positive and negative ED were both associated with less distress, and better well-being and physical functioning. Overall ED was unexpectedly related to worse outcomes (i.e., more distress, less well-being, decreased physical functioning). Stress did not moderate the relationship between emotional complexity and the outcome variables.
Conclusions: Different indicators of EC represent distinct aspects of emotional experience. Partial support of the hypotheses found. Physical functioning was the only outcome influenced by EC. The inclusion of stress did not change the results. The discrepancy between the findings and those in the literature may be related to reliability of EC indicators and absence of contextual factors. Further exploration of ED revealed a potentially important construct of emotional experience that is deserving of further inquiry.
Epigenetic inheritance plays an important role in mediating alternative phenotype in highly social species. In order to gain a greater understanding of epigenetic effects in societies, we investigated DNA methylation in the termite Zootermopsis nevadensis. Termites are the most ancient social insects, and developmentally distinct from highly-studied, hymenopteran social insects. We used replicated bisulfite-sequencing to investigate patterns of DNA methylation in both sexes and among castes of Z. nevadensis. We discovered that Z. nevadensis displayed some of the highest levels of DNA methylation found in insects. We also found strong differences in methylation between castes. Methylated genes tended to be uniformly and highly expressed demonstrating the antiquity of associations between intragenic methylation and gene expression. Differentially methylated genes were more likely to be alternatively spliced than not differentially methylated genes, and possessed considerable enrichment for development-associated functions. We further observed strong overrepresentation of multiple transcription factor binding sites and miRNA profiles associated with differential methylation, providing new insights into the possible function of DNA methylation. Overall, our results show that DNA methylation is widespread and associated with caste differences in termites. More generally, this study provides insights into the function of DNA methylation and the success of insect societies.
Although eusociality evolved independently within several orders of insects, research into the molecular underpinnings of the transition towards social complexity has been confined primarily to Hymenoptera (for example, ants and bees). Here we sequence the genome and stage-specific transcriptomes of the dampwood termite Zootermopsis nevadensis (Blattodea) and compare them with similar data for eusocial Hymenoptera, to better identify commonalities and differences in achieving this significant transition. We show an expansion of genes related to male fertility, with upregulated gene expression in male reproductive individuals reflecting the profound differences in mating biology relative to the Hymenoptera. For several chemoreceptor families, we show divergent numbers of genes, which may correspond to the more claustral lifestyle of these termites. We also show similarities in the number and expression of genes related to caste determination mechanisms. Finally, patterns of DNA methylation and alternative splicing support a hypothesized epigenetic regulation of caste differentiation.