Male–male competition may interfere with the ability of females to choose mates by interrupting courtship or by favoring highly aggressive males who may damage females during mating attempts. Alternatively, females may benefit by mating with dominant males, and female choice and male–male competition may therefore act in unison. The same traits, including aggressiveness, may indicate male quality to females and to rivals. We investigated sexual selection in the black morph of the endemic Cuban poeciliid fish, Girardinus metallicus, to ascertain the links between morphological and behavioral traits and success in intra‐ and intersexual selection. Males conspicuously exhibit their black ventral surface and gonopodium to females during courtship. Dichotomous choice tests revealed female association preferences for certain males, and those same males were more successful in monopolizing access to females when the fish were allowed to directly interact. Dominant males followed, courted, and copulated with females more than subordinate males within a pair, and it appears that females could either assess dominance based on cues we did not measure, or could influence subsequent mating success by their behavior during the dichotomous choice trials. There was an interaction between black status (i.e., whether the male in each pair had more or less ventral black coloration than the other male in that pair) and dominance, such that low‐black dominant males courted early and then shifted to following females, whereas high‐black dominant males courted far more later in the observation period. These results hint at the importance for sexual selection of the interplay between a static morphological trait (black coloration) and a dynamic behavioral trait (aggressiveness), but the functional significance of the courtship display remains a mystery.

Background: Though a growing body of research suggests that greater positive psychological well-being in irritable bowel syndrome (IBS) may be protective, existing brain-gut behavior therapies primarily target negative psychological factors. Little is known about how positive psychological factors in IBS relate to IBS symptoms, health-related quality of life (HRQoL), or adherence to key health behaviors, such as physical activity and diet modification. Accordingly, per the ORBIT model of behavioral treatment development for chronic diseases, we explored potential connections between psychological constructs and IBS symptoms, health behavior engagement (physical activity and dietary modification), and HRQoL in a qualitative study to inform the development of a novel brain-gut behavior therapy. Methods: Participants with IBS completed self-report assessments and semistructured phone interviews about relationships between positive and negative psychological constructs, IBS symptoms, health behavior engagement, and HRQoL. Key Results: Participants (n = 23; 57% female) ranged in age from 25 to 79 (mean age = 54). IBS subtypes were similarly represented (IBS-diarrhea [n = 8], IBSconstipation [n = 7], and IBS-mixed [n = 8]). Participants described opposing relationships between positive and negative psychological constructs, IBS symptoms, health behavior engagement, and HRQoL, respectively, such that experiencing positive constructs largely mitigated IBS symptoms, boosted health behavior participation, and improved HRQoL, and negative constructs exacerbated symptoms, reduced health behavior participation, and worsened HRQoL. Conclusions and Inferences: Participants with IBS linked greater positive psychological well-being to moderated IBS symptoms and better HRQoL and health behavior participation. An intervention to cultivate greater well-being may be a novel way to mitigate IBS symptoms, boost health behavior participation, and improve HRQoL in IBS.

The effects of common anaesthetics on the hue, saturation and brightness measurements of the poeciliid fish Girardinus metallicus were investigated in two experiments. For both experiments the coloration of four body regions was measured from digital images of the same males obtained under three conditions: (1) control (in a water‐filled chamber); (2) anaesthetised with MS‐222; and (3) anaesthetised with eugenol (clove oil). In experiment 1 anaesthetised fish were photographed out of water. In experiment 2 all photographs were taken in a water‐filled chamber. Anaesthetics altered coloration in both experiments. In the more methodologically consistent experiment 2 we found significantly different hue, increased saturation and decreased brightness in anaesthetic v. control conditions, consistent with darkening caused by the anaesthetics. The body regions differed in coloration consistent with countershading but did not differentially change in response to anaesthesia. These findings suggest that photographing fish in a water‐filled chamber without anaesthetic is preferable for obtaining digital images for colour analysis and that multiple body regions of fish should be measured when assessing coloration patterns meaningful in behavioural contexts, to account for the gradients caused by countershading. We are encouraged that some researchers employ such methods already and caution against using anaesthetics except when absolutely necessary for immobilisation.

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Background/Objectives: This pilot randomized controlled trial aimed to help people with metabolic syndrome increase physical activity and well-being. Intervening on lifestyle behaviors such as physical activity, can improve metabolic syndrome outcomes. Methods: Primary care patients with metabolic syndrome were recruited from clinics across our hospital system. Eligibility criteria were: <150 minutes/week of moderate-vigorous physical activity (MVPA), having ≥2 of 5 metabolic syndrome criteria, and not having cardiovascular disease or diabetes, as this was a prevention study. The multilevel intervention (MAPP) included 8-weekly 60-minute group sessions, physical activity self-monitoring/goal setting using Fitbits, physical activity/motivational interviewing (MI) topics, positive psychology (PP) topics, a weekly group walk prior to COVID, and neighborhood walkability assessments. Participants were randomized to an immediate or waitlist control group. They wore an Actigraph GT3X+ accelerometer for one week before beginning and after the last session (8-weeks). We obtained pre-post weight measurements. Mean baseline to 8-week individual difference results were compared between groups using t-tests with unequal variances. Results: Sixty-four participants enrolled, with 32 randomized to each arm; 51 provided complete follow-up data, and 63% (10/16) of the groups were conducted virtually (post-COVID). Most (92%; 59/64) were non-Hispanic White, 69% (44/64) were female, and mean age was 60. Average daily physical activity did not increase significantly by objective measures. The estimated change in mean difference for sedentary time decreased for the intervention group compared to the control group by 46.8 minutes/day (CI: -47.5-141.1; d= 0.28). Light physical activity increased by an average of 21.0 minutes/day (CI: -13.9-55.9; d= 0.34), steps/day increased by 376.6 (CI: -949.6-1702.9; d =0.16), and moderate-vigorous physical activity increased by 4.1 minutes/day (CI: -4.5-12.8; d=0.27). The estimated change in mean weight was significant: 8.4 pounds lost for the intervention group compared to the control group (CI: -13.5-3.2; p =.002; d =0.92). Discussion: This 8-week randomized controlled trial of a multilevel physical activity PP-MI intervention was associated with small to medium effect sizes for changes in physical activity, and a significant decrease in weight, despite weight not being an intervention target. Changes of this magnitude are associated with reduced cardiovascular disease risk and mortality. These findings are all in expected directions, producing signals even amidst different modalities and COVID-19-related disruptions. We plan to test this in a larger efficacy trial with broader reach and implementation.