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The environment plays an important role in the movement of individuals and their associated genes among populations, which facilitates gene flow. Gene flow can help maintain the genetic diversity both within and between populations and counter the negative impact of genetic drift, which can decrease the fitness of individuals. Sympatric species can have different habitat preferences, and thus can exhibit different patterns of genetic variability and population structure. The specialist-generalist variation hypothesis (SGVH) predicts that specialists will have lower genetic diversity, lower effective population sizes (Ne), and less gene flow among populations. In this study, we used spatially explicit, individual-based comparative approaches to test SGVH predictions in two sympatric cottontail species and identify environmental variables that influence their gene flow. New England cottontail (Sylvilagus transitionalis) is the only native cottontail in the Northeast US, an early successional habitat specialist, and a species of conservation concern. Eastern cottontail (S. floridanus) is an invasive species in the Northeast US and a habitat generalist. We characterized each species' genomic variation by developing double-digest Restriction-site Associated DNA sequence single nucleotide polymorphism markers, quantified their habitat with Geographic Information System environmental variables, and conducted our analyses at multiple scales. Surprisingly, both species had similar levels of genetic diversity and eastern cottontail's Ne was only higher than New England cottontail in one of three subregions. At a regional level, the population clusters of New England cottontail were more distinct than eastern cottontail, but the subregional levels showed more geographic areas of restricted gene flow for eastern cottontail than New England cottontail. In general, the environmental variables had the predicted effect on each species' gene flow. However, the most important environmental variable varied by subregion and species, which shows that location and species matter. Our results provide partial support for the SGVH and the identification of environmental variables that facilitate or impede gene flow can be used to help inform management decisions to conserve New England cottontail.

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This parallel randomized controlled trial aimed to evaluate the effect of acceptance and commitment therapy (ACT) focused on disrupting repetitive negative thinking (RNT) versus a waitlist control (WLC) in the treatment of depression and generalized anxiety disorder (GAD). Forty-eight participants with a main diagnosis of depression and/or GAD were allocated by means of simple randomization to a 2-session RNT-focused ACT intervention or to the WLC. The primary outcomes were emotional symptoms as measured by the Depression, Anxiety, and Stress Scales-21. Process outcomes included ACT- and RNT-related measures: general RNT, experiential avoidance, cognitive fusion, values, and generalized pliance. At the 1-month follow-up, linear mixed effects models showed that the intervention was efficacious in reducing emotional symptoms (d = 2.42, 95% confidence interval [1.64, 3.19]), with 94.12% of participants in the RNT-focused ACT condition showing clinically significant change in the Depression, Anxiety, and Stress Scales-21 total scores versus 9.09% in the WLC condition (70% vs. 8% in intention-to-treat analysis). The intervention effects were maintained at the 3-month follow-up. No adverse events were found. A very brief RNT-focused ACT intervention was highly effective in the treatment of depression and GAD. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

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Young adults suffering from generalized anxiety disorder (GAD) show high levels of worry about different domains, with couple relationships being the most frequent one. Excessive worry in this domain might lead to couple dysfunction, which is associated with lower outcomes of cognitive behavioral therapy. The current study analyzes the effect of an individual, 3-session, acceptance and commitment therapy (ACT) protocol focused on repetitive negative thinking (RNT) in the treatment of GAD with couple relationship as the main worry domain. Three young adults with GAD participated in this study. A delayed multiple-baseline design was implemented. All participants completed a 5 to 7-week baseline without showing improvement trends in couple-related worry (Experiences in Close Relationships -Anxiety; ECR-A) and general pathological worry (Penn State Worry Questionnaire; PSWQ). Afterwards, they received the ACT protocol, and a 3-month follow-up was conducted. All 3 participants showed evidence of intervention effects on the ECR-A and PSWQ. The standardized mean difference effect sizes for single-case experimental design were very large for the ECR-A (g= 5.93) and PSWQ (g= 3.19). No adverse events were found. Brief, RNT-focused ACT protocols for treating GAD with couple relationship as the main worry domain deserve further empirical tests

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The oceans are deteriorating at a fast pace. Conservation measures, such as Marine Protected Areas, are being implemented to relieve areas from local stressors and allow populations to restore to natural levels. Successful networks of MPAs operate if the space among MPAs is smaller than the dispersal capacity of the species under protection. We studied connectivity patterns across populations in a series of MPAs in the common yellowhead Jawfish, Opistognathus aurifrons. Using the power of genome-wide variation, we estimated that the maximum effective dispersal is 8.3 km. We found that MPAs exchange migrants likely via intermediate unprotected habitats through stepping stone dispersal. At scales >50 km such connectivity is decreased, particularly across the Mona Passage. The MPA network studied would be unable to maintain connectivity of these small benthic fishes if habitat in between them is extirpated. Our study highlights the power of SNPs to derive effective dispersal distance and the ability of SNPs to make inferences from single individuals. Given that overall reef fish diversity is driven by species with life histories similar to that of the yellowhead jawfish, managers face a challenge to develop strategies that allow connectivity and avoid isolation of populations and their possible extinction.

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The General Health Questionnaire - 12 (GHQ-12) is a widely used screening self-report for emotional disorders among adults. However, there is little evidence concerning the validity of the GHQ-12 in Colombia and its factorial invariance between nonclinical and clinical samples. Accordingly, the current study aims to explore the GHQ-12 validity in Colombian nonclinical and clinical samples. The GHQ-12 was administered to a total of 1641 participants, including a sample of undergraduates, one of general population, and a clinical sample. The internal consistency of the GHQ-12 across samples was good (overall alpha of .90). The one-factor model showed a good fit to the data and was considered theoretically more coherent than the two-factor model with positive and negative items loading in separate factors. Metric and scalar invariance were observed across nonclinical and clinical samples. The GHQ-12 scores were strongly and positively related to emotional symptoms and experiential avoidance, and negatively related to life satisfaction. According to the receiver operating characteristic (ROC) curves, a threshold score of 11/12 was optimal to identify emotional disorders. In conclusion, the GHQ-12 is a valid screening self-report in Colombia that provides scores that can be compared across clinical and nonclinical participants.

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Shallow water anthozoans, the major builders of modern coral reefs, enhance their metabolic and calcification rates with algal symbionts. Controversy exists over whether these anthozoan-algae associations are flexible over the lifetimes of individual hosts, promoting acclimative plasticity, or are closely linked, such that hosts and symbionts co-evolve across generations. Given the diversity of algal symbionts and the morphological plasticity of many host species, cryptic variation within either partner could potentially confound studies of anthozoan-algal associations. Here, we used ribosomal, organelle and nuclear sequences, along with microsatellite variation, to study the relationship between lineages of a common Caribbean gorgonian and its algal symbionts. The gorgonian Eunicea flexuosa is a broadcast spawner, composed of two recently diverged, genetically distinct lineages largely segregated by depth. We sampled colonies of the two lineages across depth gradients at three Caribbean locations. We find that each host lineage is associated with a unique Symbiodinium B1/184 phylotype. This relationship between host and symbiont is maintained when host colonies are reciprocally transplanted, although cases of within phylotype switching were also observed. Even when the phylotypes of both partners are present at intermediate depths, the specificity between host and symbiont lineages remained absolute. Unrecognized cryptic diversity may mask host-symbiont specificity and change the inference of evolutionary processes in mutualistic associations. Symbiotic specificity thus likely contributes to the ecological divergence of the two partners, generating species diversity within coral reefs.

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