Laboratory research has shown that age can be estimated with mean absolute errors of approximately five years for faces and ten years for voices. However, it is less clear how precise such age estimates are in real-world settings, where observers often judge from a distance with less controlled and more variable access to facial and vocal cues. This proof-of-concept study assessed the feasibility of examining age estimation under ecologically valid conditions through naturalistic observation in public settings. Two observers estimated the ages of 565 strangers in public from a distance and subsequently approached each individual to record their self-reported age. The findings demonstrate that age estimation can be feasibly conducted in a systematic way through naturalistic observation, with preliminary evidence suggesting that the resulting mean absolute error was comparable to—and possibly lower than—errors reported in laboratory studies. While tentative, these results highlight the potential of studying age estimation in public contexts and support further observational research with larger and more diverse samples.
Many studies have focused on the attractiveness of physical characteristics of the human body, but few have examined extracorporeal attributes. This study investigated whether inherent visual characteristics of necklaces contribute to their attractiveness. Using questionnaires, preferences for nine visual variables were tested across three European regions (France, Germany and the Netherlands). Four variables were linked to the beads themselves (shape, color, shade, and size), and five concerned the overall visual appearance of the necklace (homogeneity, symmetry, contrast with background, number of strands, and length). Despite small sample sizes ( N = 32 for France, N = 69 for Germany, N = 42 for the Netherlands), results across all three regions showed a consistent preference for single-strand necklaces composed of small, white, rounded beads arranged symmetrically and homogeneously on a relatively short string. No significant differences were found between female and male participants. These findings suggest a possible bio-psychological foundation for the appreciation of beauty and attractiveness in extracorporeal elements.
Life History Theory explains how environmental conditions can lead to adaptive behaviors in adulthood. One of the factors that impact early psychological development and adult well-being is the family unpredictability experienced during childhood, i.e., inconsistent parental provision of basic needs (e.g., emotional nurturance, financial stability, and meal regularity). The aim of this study was to explore the impact of childhood family unpredictability on subjective well-being and unpredictability beliefs among adults during the COVID-19 pandemic. We conducted survey-type research with a quasi-experimental design involving 422 participants who completed online questionnaires on perceptions of childhood family unpredictability and current levels of subjective well-being and unpredictability beliefs. Based on their childhood perceptions, participants were categorized into three groups: low overall unpredictability, mixed unpredictability, and high overall unpredictability. We found that the low overall unpredictability group reported higher levels of subjective well-being and lower levels of self-unpredictability beliefs compared to the other two groups. Participants in the mixed unpredictability group reported moderate levels of both subjective well-being and self-unpredictability beliefs compared to the other two groups. Regarding levels of world unpredictability beliefs, all groups exhibited similar patterns. In this case, the pandemic may increase perceptions of world unpredictability, potentially overshadowing childhood experiences of predictability. Notably, the predictability in family emotional support during childhood had a significant influence on adult behavior, surpassing the impact of financial unpredictability. Our findings stress the role of family predictability in aspects related to quality of life, highlighting that beliefs related to unpredictability may lead to less healthy coping strategies in response to adversity compared to those who perceive their environment as predictable.
Collaboration is not just something humans do; it is a condition we live in. The Nature and Dynamics of Collaboration offers a timely and wide-ranging examination of how collaboration shapes human life—from its evolutionary roots to its role in contemporary science, institutions, and global challenges. The book brings together diverse examples, frameworks, and perspectives, arguing that while collaboration takes many forms, certain structures and processes are shared. It explores both what makes collaborations work and why they fail. As we face urgent collective crises, especially climate change and growing polarization, this book suggests that studying collaboration is not only intellectually important, but existentially necessary.
