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Investigating the effects of climatic variability on biological diversity, productivity, and stability is key to understanding possible futures for ecosystems under accelerating climate change. A critical question for estuarine ecosystems is, how does climatic variability influence juvenile recruitment of different fish species and life histories that use estuaries as nurseries? Here we examined spatiotemporal abundance trends and environmental responses of 18 fish species that frequently spend the juvenile stage rearing in the San Francisco Estuary, CA, USA. First, we constructed multivariate autoregressive state-space models using age-0 fish abundance, freshwater flow (flow), and sea surface temperature data (SST) collected over four decades. Next, we calculated coefficients of variation (CV) to assess portfolio effects (1) within and among species, life histories (anadromous, marine opportunist, or estuarine dependent), and the whole community; and (2) within and among regions of the estuary. We found that species abundances varied over space and time (increasing, decreasing, or dynamically stable); and in 83% of cases, in response to environmental conditions (wet/dry, cool/warm periods). Anadromous species responded strongly to flow in the upper estuary, marine opportunist species responded to flow and/or SST in the lower estuary, and estuarine dependent species had diverse responses across the estuary. Overall, the whole community when considered across the entire estuary had the lowest CV, and life histories and species provided strong biological insurance to the portfolio (2.4- to 3.5-fold increases in stability, respectively). Spatial insurance also increased stability, although to a lesser extent (up to 1.6-fold increases). Our study advances the notion that fish recruitment stability in estuaries is controlled by biocomplexity-life history diversity and spatiotemporal variation in the environment. However, intensified drought and marine heatwaves may increase the risk of multiple consecutive recruitment failures by synchronizing species dynamics and trajectories via Moran effects, potentially diminishing estuarine nursery function.

Executive function (EF) skills are a set of attention-regulation skills involved in intentional, goal-directed behavior that include (but are not limited to) the cool EF skills of working memory, cognitive flexibility, and inhibitory control, and also the hot EF skill of intentional reevaluation. These skills are inevitably expressed in goal- and context-dependent ways, leading some to view EF skills as specific adaptations to particular problems and reinforcing interest in the use of more ecologically contextualized assessments. Appreciation of the context-dependency of EF skills adds to our understanding of how EF skills develop as a consequence of particular experiences and how they contribute to key developmental outcomes. There are good reasons, however, to view EF skills as relatively domain-general neurocognitive skills. Measured using standardized direct behavioral assessments, these skills are associated reliably with well-defined but distinct neural networks; they predict long-term developmental outcomes; and they can be trained in ways that produce far transfer. We argue that developmental systems models of EF skills can reconcile views of EF skills as relatively domain-general and views that emphasize the context-dependency of these skills. Ecologically adapted measures of EF skills can complement standardized measures that capture important age-related and individual differences and should remain a cornerstone of research on the topic. We believe this type of model will facilitate a deeper understanding of how multiple, simultaneous, and interacting causal influences, operating at many levels of analysis (cultural, social, cognitive, neural, and molecular), work together to produce conscious control.

Despite growing evidence of spatial dispersal and gene flow between salmonid populations, the implications of connectivity for adaptation, conservation, and management are still poorly appreciated. Here, we explore the influence of a gradient of dispersal rates on portfolio strength and eco-evolutionary dynamics in a simulated population network of Atlantic salmon (Salmo salar) by extending a demo-genetic agent-based model to a spatially explicit framework. Our model results highlight a nonlinear relationship between dispersal rates and the stability of the metapopulation, resulting in an optimal portfolio effect for dispersal rates around 20%. At local population scale, we also demonstrate phenotypic changes induced by density-dependent effects modulated by dispersal, and a dispersal-induced increase in genetic diversity. We conclude that it is critical to account for complex interactions between dispersal and eco-evolutionary processes and discuss future avenues of research that could be addressed by such modeling approaches to more fully appreciate responses of Atlantic salmon to environmental changes and investigate management actions accordingly. Key words: Atlantic salmon, demo-genetic agent-based model, dispersal, eco-evolutionary dynamics, metapopulation, portfolio effect, synchrony Malgre des preuves de plus en plus abondantes de dispersion spatiale et de flux genetique entre populations de salmonides, les consequences de la connectivite en ce qui concerne l'adaptation, la conservation et la gestion demeurent mal comprises. Nous explorons l'influence d'un gradient de taux de dispersion sur la force du portefeuille et les dynamiques eco-evolutives d'un reseau de populations simule de saumon atlantique (Salmo salar) en elargissant un modele demo-genetique base sur les agents a un cadre spatialement explicite. Les resultats du modele font ressortir une relation non lineaire entre les taux de dispersion et la stabilite de la metapopulation, qui se traduit par un effet de portefeuille optimal pour des taux de dispersion d'environ 20 %. Nous demontrons aussi la presence de changements phenotypiques a l'echelle de la population locale induits par des effets dependants de la densite modules par la dispersion, ainsi qu'une augmentation de la diversite genetique induite par la dispersion. Nous concluons qu'il est d'importance capitale de tenir compte des interactions complexes entre la dispersion et les processus eco-evolutifs et abordons des avenues de recherche future pouvant etre explorees a l'aide de telles approches de modelisation pour mieux comprendre les reponses du saumon atlantique aux changements environnementaux et examiner differentes mesures de gestion. [Traduit par la Redaction] Mots-cles : saumon atlantique, modele demo-genetique base sur les agents, dispersion, dynamique eco-evolutive, metapopulation, effet de portefeuille, synchronie, 1. Introduction Rapid environmental changes and associated selection pressures are affecting the adaptive capacity and persistence of many species globally (Ceballos et al. 2015). Consequently, there is considerable interest in [...]

Many changes were thrust upon families by the COVID-19 pandemic, including mandated quarantines, social distancing, transitions to distance learning for children, and remote work. The current study used mixed methods to examine the challenges and resilience of families in the United States during the pandemic (May-July 2020), as well as predictors and moderators of parent/child psychological distress. Our sample included 469 parents (459 mothers) of children aged [approximately]2-13 years (239 girls, 228 boys, one nonbinary child, one "prefer not to answer" selection), who completed an online survey with closed-ended and open-ended portions. The sample had middle-to-high socioeconomic status and 86% of families were White/non-Hispanic. Qualitative (content and thematic analyses) and quantitative (descriptive statistics and regressions) findings revealed that, even in this relatively privileged sample, parents and families were experiencing struggles in many life domains (e.g., family, school) and shifts in family dynamics and routines, which were related to emotional and mental health. Families experienced many changes in their lives, some positive and some negative, and often exhibited resilience through managing these changes. Our moderation analyses indicated that COVID-19's daily impact was significantly associated with psychological distress for children and parents, and this association was stronger for older versus younger children. Less active/instructive parental media mediation was also related to less child psychological distress. Moving forward, practitioners can focus on preventive efforts including psychoeducation regarding healthy outlets for negative emotions during COVID-19, and practical help troubleshooting childcare and health care challenges impacting many families.

Migration is a complex trait that often has genetic underpinnings. However, it is unclear if migratory behaviour itself is inherited (direct genetic control), or if the decision to migrate is instead the outcome of a set of physiological traits (indirect genetic control). For steelhead/rainbow trout (Oncorhynchus mykiss), migration is strongly linked to a large genomic region across their range. Here, we demonstrate a shared allelic basis between early life growth rate and migratory behaviour. Next, we demonstrate that early life growth differs among resident/migratory genotypes in wild juveniles several months prior to migration, with resident genotypes achieving a larger size in their first few months of life than migratory genotypes. We suggest that the genetic basis of migration is likely indirect and mediated by physiological traits such as growth rate. Evolutionary benefits of this indirect genetic mechanism likely include flexibility among individuals and persistence of life-history diversity within and among populations.

Historically, many biologists assumed that evolution and ecology acted independently because evolution occurred over distances too great to influence most ecological patterns. Today, evidence indicates that evolution can operate over a range of spatial scales, including fine spatial scales. Thus, evolutionary divergence across space might frequently interact with the mechanisms that also determine spatial ecological patterns. Here, we synthesize insights from 500 eco-evolutionary studies and develop a predictive framework that seeks to understand whether and when evolution amplifies, dampens, or creates ecological patterns. We demonstrate that local adaptation can alter everything from spatial variation in population abundances to ecosystem properties. We uncover 14 mechanisms that can mediate the outcome of evolution on spatial ecological patterns. Sometimes, evolution amplifies environmental variation, especially when selection enhances resource uptake or patch selection. The local evolution of foundation or keystone species can create ecological patterns where none existed originally. However, most often, we find that evolution dampens existing environmental gradients, because local adaptation evens out fitness across environments and thus counteracts the variation in associated ecological patterns. Consequently, evolution generally smooths out the underlying heterogeneity in nature, making the world appear less ragged than it would be in the absence of evolution. We end by highlighting the future research needed to inform a fully integrated and predictive biology that accounts for eco-evolutionary interactions in both space and time.

Landscape permeability is often explored spatially, but may also vary temporally. Landscape permeability, including partial barriers, influences migratory animals that move across the landscape. Partial barriers are common in rivers where barrier passage varies with streamflow. We explore the influence of partial barriers on the spatial and temporal distribution of migration-linked genotypes of Oncorhynchus mykiss, a salmonid fish with co-occurring resident and migratory forms, in tributaries to the South Fork Eel River, California, USA, Elder and Fox Creeks. We genotyped >4,000 individuals using RAD-capture and classified individuals as resident, heterozygous or migratory genotypes using life history-associated loci. Across four years of study (2014-2017), the permeability of partial barriers varied across dry and wet years. In Elder Creek, the largest waterfall was passable for adults migrating up-river 4-39 days each year. In this stream, the overall spatial pattern, with fewer migratory genotypes above the waterfall, remained true across dry and wet years (67%-76% of migratory alleles were downstream of the waterfall). We also observed a strong relationship between distance upstream and proportion of migratory alleles. In Fox Creek, the primary barrier is at the mouth, and we found that the migratory allele frequency varied with the annual timing of high flow events. In years when rain events occurred during the peak breeding season, migratory allele frequency was high (60%-68%), but otherwise it was low (30% in two years). We highlight that partial barriers and landscape permeability can be temporally dynamic, and this effect can be observed through changing genotype frequencies in migratory animals.

Many migratory species, from monarch butterflies to wildebeest, express partial migration, where only a subset of a population migrates. This intraspecific variation is likely to have large ecological consequences. We studied the ecological consequences of partial migration in a salmonid fish, Oncorhynchus mykiss , in coastal streams in California, USA. One ecotype, steelhead trout, migrates to the ocean, whereas the other, rainbow trout, completes its lifecycle in freshwater. Migration has a strong genetic basis in O. mykiss . In one stream, we found differences in the frequency of migration‐linked genotypes below and above a waterfall barrier (migratory allele frequency of 60% below vs. 31% above). Below the waterfall, in the migratory‐dominated region, the density of young fish (1 yr old) in pools downstream of the waterfall (0.05 vs. 0.13 individuals/m2). In a second stream, between‐year variation in the dominance of migratory vs. resident fish allowed us to explore differences in fish density and size structure through time, and we found a consistent pattern. In brief, when migratory genotypes dominated, we found higher densities of young fish and lower densities of older fish, resulting in a simpler size structure, compared to when resident genotypes dominated. Moreover, large resident trout had a slightly higher trophic position than young fish (3.92 vs. 3.42 in one creek and 3.77 vs. 3.17 in the other), quantified with stable isotope data. The difference in fish size structure did not generate trophic cascades. Partial migration is widespread among migratory populations, as is phenotypic divergence between resident and migratory forms, suggesting the potential for widespread ecological effects arising from this common form of intraspecific variation.

Dispersal and shared environmental conditions can both synchronize the dynamics of local populations, but disentangling their relative influence on dynamics is challenging. We used a Bayesian approach to estimate the synchrony of a metapopulation of Atlantic salmon (Salmo salar) composed of 18 populations in Brittany, France, including a 24-year time series of the abundances of juveniles. We estimated the spatial synchrony at a regional and local spatial scale over the study period. We found a strong regional synchrony despite spatiotemporal variability of local synchrony in the abundance of juveniles. We then explored the drivers of synchrony, including environmental conditions (aspects of river flow) and abundance of adult breeders. This revealed that summer low-flow conditions seemed to synchronize the abundances of juveniles more than the synchrony in the abundance of adult breeders, suggesting a Moran effect. Given that drought conditions are expected to become more common with climate change, our work highlights the potentially strong synchronizing effect of summer low flow on the dynamics of local salmon populations and the benefits of considering synchrony at multiple scales. Si la dispersion et des conditions environnementales similaires peuvent toutes deux synchroniser la dynamique de populations locales, il peut etre difficile de departager leurs influences respectives sur cette dynamique. Nous avons utilise une approche Bayesienne pour estimer la synchronie d'une metapopulation de saumons atlantiques (Salmo salar) composee de 18 populations en Bretagne (France), sur la base d'une serie de 24 ans de donnees d'abondance des juveniles. Nous avons estime la synchronie spatiale aux echelles regionale et locale durant la periode a l'etude. Nous avons releve une forte synchronie regionale malgre la variabilite spatiotemporelle de la synchronie locale de l'abondance des juveniles. Nous nous sommes ensuite penches sur les facteurs generant cette synchronie, parmi lesquels les conditions ambiantes (differents aspects du debit des rivieres) et l'abondance des geniteurs. Cette analyse a revele que des conditions de faible debit estival semblent synchroniser l'abondance des juveniles plus que la synchronie de l'abondance des geniteurs, ce qui indiquerait un effet Moran. Au vu de la frequence accrue de conditions de secheresse a prevoir en raison du changement climatique, nos travaux soulignent l'effet de synchronisation potentiellement marque de faibles debits estivaux sur la dynamique des populations locales de saumons et les avantages de tenir compte de la synchronie a differentes echelles. [Traduit par la Redaction], 1. Introduction Spatial synchrony describes the pattern of spatial autocorrelation in the dynamics of a set of local populations (Bjornstad et al. 1999a; Walter et al. 2017). High spatial synchrony [...]

This mixed methods study examined parent-reported child screen media use before and during the COVID-19 pandemic by examining 2019-2020 changes in parent perceptions of media, screen media use (SMU), and problematic media use (PMU) in children aged 2-13 years (N = 129; 64 boys, 64 girls, 1 nonbinary; 90.7% White, 4.6% Hispanic/Latino, 0.8% Black, 8.5% multiethnic; primarily middle-to-high income). Quantitative analyses showed a significant SMU and PMU increase (medium effect size). There was a steeper increase in PMU among school-age (older) children. Together, the qualitative and quantitative results suggest that the PMU and SMU increase were influenced by distal, proximal, and maintaining factors including the COVID-19 pandemic, distance learning, child behaviors, other children, parental mediation, and positive media reinforcement.

Dispersal is a ubiquitous ecological process that has been extensively studied in many plants and animals. Anadromous salmonids are an interesting system for examining dispersal, in part because of their well‐known philopatric behaviour, but also because of the conservation challenges related to the dispersal of hatchery‐origin fish. Building on earlier work, we provide an updated systematic review of dispersal and gene flow in anadromous salmonids. In particular, we compared studies on the dispersal of anadromous salmonids from wild and hatchery origins, including studies providing estimates of dispersal rates, observations of dispersal and results from modelling studies. We reviewed 228 studies and found these were unevenly distributed among species, with Atlantic salmon, Chinook salmon and sea trout being well‐represented. Our results showcase considerable variability in estimated dispersal rates within and across studies, which is likely related to the different methodologies, dispersal propensities across species and populations, and spatial extents considered. Overall, our results confirmed a higher tendency of hatchery fish to disperse relative to wild fish, but we also found some variation across species that warrants further study. Moreover, we found that dispersal propensity tended to decline exponentially with distance and that the drivers of dispersal varied considerably among studies. Additionally, we highlight various facets of dispersal captured across this suite of studies, including variation in terminology, methods and metrics for characterising dispersal, and the spatio‐temporal scales considered. Finally, our review revealed that few studies considered, and even fewer assessed, the implications of dispersal for the conservation and management of anadromous salmonids. [ABSTRACT FROM AUTHOR]

California’s salmonids are at the southern limits of their individual species’ ranges, and display a wide diversity of strategies to survive in California’s highly variable climate. Land use changes after statehood in 1850 eliminated important habitats, or blocked access to them, and reduced the abundance, productivity, and distribution of California’s salmon. Habitat simplification, fishing, hatchery impacts, and other stressors led to the loss of genetic and phenotypic (life history, morphological, behavioral, and physiological) diversity in salmonids. Limited diversity and habitat loss left California salmon with reduced capacity to cope with a variable and changing climate. Since 1976, California has experienced frequent droughts, as were common in the paleo-climatological record, but rare in the peak dam-building era of 1936–1976. Increasing temperatures and decreasing snowpacks have produced harsher conditions for California’s salmon in their current habitats than they experienced historically. The most likely way to promote salmon productivity and persistence in California is to restore habitat diversity, reconnect migratory corridors to spawning and rearing habitats, and refocus management to replenish the genetic and phenotypic diversity of these southernmost populations.

In 1978, the Golden Trout Wilderness area was established to protect the California golden trout (Oncorhynchus mykiss aguabonita)—a vulnerable subspecies of the rainbow trout that is endemic to California—and its habitat, which is currently restricted to a few streams within high-elevation meadows in the Sierra Nevada Mountain Range. Because of the deleterious effects of livestock grazing on riparian vegetation in the golden trout habitat (occurring since the 1800s), meadow restoration activities were initiated in 1991, including cattle exclusion. There has been renewed discussion about re-opening these public lands to livestock grazing, and impact assessment studies are needed to inform decision makers about the potential consequences. Thus, we estimated the recovery potential of the golden trout habitat by measuring the height of riparian vegetation within areas that have been grazed vs. closed to grazing (“rested”) since 1991. We found that cattle exclusion is effective at favoring riparian vegetation growth, but that vegetation recovery from grazing could take several decades in these sensitive habitats as some “rested” areas have yet to recover to full vegetation height, even after 25 yr of rest.

The connection between brain rhythms at rest and cognition remains poorly understood. This is especially true during early childhood in which neuroimaging data are relatively scarce. We developed a new method for collecting eyes closed and eyes open resting state electroencephalography (EEG) suitable for young children. We report results characterizing age-related change in power in multiple brain rhythms over frontal and posterior regions under eyes closed and open conditions of rest in 3-, 4-, 5- and 9-year-old children (N = 162). We observed two key patterns of results. First, with age theta decreased, alpha increased, and alpha peak frequency increased. Second, power was generally higher when eyes were closed than open for theta and alpha but higher when eyes were open than closed for beta and gamma. We also investigated the relation between resting state EEG activity and executive function (EF) using the Minnesota Executive Function Scale, a standardized behavioral measure of EF for ages 2 and up. Correlational and regression analyses showed that individual differences in the theta/beta ratio is associated with EF even after controlling for children's age and verbal abilities. We situate our results in a theoretical discussion of theta/beta and its role in control processes.

Urbanization is one of the leading threats to freshwater biodiversity, and urban regions continue to expand globally. Here we examined the relationship between recent urbanization and shifts in stream fish communities. We sampled fishes at 32 sites in the Alameda Creek Watershed, near San Francisco, California, in 1993–1994 and again in 2009, and we quantified univariate and multivariate changes in fish communities between the sampling periods. Sampling sites were classified into those downstream of a rapidly urbanizing area (“urbanized sites”), and those found in less impacted areas (“low-impacted sites”). We calculated the change from non-urban to urban land cover between 1993 and 2009 at two scales for each site (the total watershed and a 3km buffer zone immediately upstream of each site). Neither the mean relative abundance of native fish nor nonnative species richness changed significantly between the survey periods. However, we observed significant changes in fish community composition (as measured by Bray-Curtis dissimilarity) and a decrease in native species richness between the sampling periods at urbanized sites, but not at low-impacted sites. Moreover, the relative abundance of one native cyprinid (Lavinia symmetricus) decreased at the urbanized sites but not at low-impacted sites. Increased urbanization was associated with changes in the fish community, and this relationship was strongest at the smaller (3km buffer) scale. Our results suggest that ongoing land change alters fish communities and that contemporary resurveys are an important tool for examining how freshwater taxa are responding to recent environmental change.

Partial migration is a common phenomenon wherein populations include migratory and resident individuals. Whether an individual migrates or not has important ecological and management implications, particularly within protected populations. Within partially migratory populations of Oncorhynchus mykiss, migration is highly correlated with a specific genomic region, but it is unclear how well this region predicts migration at the individual level. Here, we relate sex and life history genotype, determined using >400 single nucleotide polymorphisms (SNPs) on the migratory-linked genomic region, to life history expression of marked juvenile O. mykiss from two tributaries to the South Fork Eel River, northern California. Most resident fish were resident genotypes (57% resident, 37% heterozygous, 6% migratory genotype) and male (78%). Most migratory fish were female (62%), but were a mixture of genotypes (30% resident, 45% heterozygous, 25% migratory genotype). Sex was more strongly correlated with life history expression than genotype, but the best-supported model included both. Resident genotypes regularly migrated, highlighting the importance of conserving the full suite of life history and genetic diversity in partially migratory populations. La migration partielle est un phenomene repandu dans lequel des populations comptent des individus migrateurs et residents. Le fait pour un individu de migrer ou non a d'importantes consequences ecologiques et en matiere de gestion, en particulier au sein de populations protegees. Au sein de populations partiellement migratrices de truites arc-en-ciel (Oncorhynchus mykiss), la migration est fortement correlee a une region precise du genome, mais la mesure dans laquelle cette region peut predire la migration au niveau individuel n'est pas bien etablie. Nous relions le sexe et le genotype du cycle biologique, determine en utilisant >400 polymorphismes mononucleotidiques (SNPs) sur la region du genome associee a la migration, a l'expression du cycle biologique d'O. mykiss juveniles marques issus de deux affluents de la riviere South Fork Eel, dans le nord de la Californie. La plupart des poissons residents presentent des genotypes de resident (57 %, 37 % et 6 %, respectivement, de genotypes de resident, d'heterozygote et de migrateur) et sont des males (78 %). La plupart des poissons migrateurs sont des femelles (62 %), mais ils presentent un melange de genotypes (30 % resident, 45 % heterozygote, 25 % migrateur). Le sexe presente une plus forte correlation avec l'expression du cycle biologique que le genotype, mais le modele qui a le plus d'appui comprend les deux. Les individus de genotype resident migrent regulierement, soulignant l'importance de conserver toute la gamme de diversite genetique et du cycle biologique dans les populations partiellement migratrices. [Traduit par la Redaction], Introduction Animal migration is an important phenomenon that allows populations to exploit different habitats throughout their life history (Dingle 2014). Many migratory populations are partially migratory, meaning they include a [...]

The liberalization of marijuana policies, including the legalization of medical and recreational marijuana, is sweeping the United States and other countries. Marijuana cultivation can have significant negative collateral effects on the environment that are often unknown or overlooked. Focusing on the state of California, where by some estimates 60%-70% of the marijuana consumed in the United States is grown, we argue that (a) the environmental harm caused by marijuana cultivation merits a direct policy response, (b) current approaches to governing the environmental effects are inadequate, and

The Central Valley fall-run Chinook salmon (Oncorhynchus tshawytscha) is the dominant population complex supporting the California and Southern Oregon commercial salmon fishery. The stock is largely dominated by hatchery productionand has shown high variability in adult returns, suggesting that hatchery practices are critical to thelong-term sustainability of the fishery. We compiled information from numerous sources to synthesizetrends in the number, location, size, and timingof fall-run Chinook salmon released from the five Central Valley hatcheries between 1946 and 2012. Approximately 2 billion fish were released duringthis period, nearly half of which were released from the single federally operated hatchery. Juveniles have been planted off-site in the estuary with increasing frequency since the early 1980s, particularly by state-operated hatcheries. Approximately 78% of all releases occurred between January and June, including ~25% in April and ~20% in May. Release timing and size trends differed among hatcheries,and were correlated. For example, the Coleman and Nimbus hatcheries tended to release small fish (10 g, on average) later in the year. Moreover, sizes-at-release (by month) haveincreased since the 1980s, leading to the emergence of a new life-history type that now comprises nearly all of the estuary releases: springtime releases of large ocean-ready “advanced smolts.” We collapsed release timing and size data into a single index of life-history diversity and our results indicate a reduction in juvenile life-history diversity, with decreased variability in release number, timing, and size through time. Together, these results indicate a reduction in the diversity of life-history types represented in the fall-run Chinook salmon hatchery releases, which may be a factor that contributes to the decreased stability of the Central Valley fall-run Chinook salmon stock complex.

In the 1960s at Stanford University's Bing Preschool, children were given the option of taking an immediate, smaller reward or receiving a delayed, larger reward by waiting until the experimenter returned. Since then, the "Marshmallow Test" has been used in numerous studies to assess delay of gratification. Yet, no prior study has compared the performance of children across the decades. Common wisdom suggests children today would wait less long, preferring immediate gratification. Study 1 confirmed this intuition in a survey of adults in the United States (N = 354; "Mdn" age = 34 years). To test the validity of this prediction, Study 2 analyzed the original data for average delay-of-gratification times (out of 10 min) of 840 typically developing U.S. children in three birth cohorts from similar middle-high socioeconomic backgrounds in the late 1960s, 1980s, and 2000s, matched on age (3 to 5 years) at the time of testing. In contrast to popular belief, results revealed a linear "increase" in delay over time (p < 0.0001, ?[subscript p][superscript 2] = 0.047), such that children in the 2000s waited on average 2 min longer than children in the 1960s, and 1 min longer than children in the 1980s. This pattern was robust with respect to age, sex, geography and sampling effects. We posit that increases in symbolic thought, technology, preschool education, and public attention to executive function skills have contributed to this finding, but caution that more research in diverse populations is needed to examine the generality of the findings and to identify causal factors.

Investigating eco‐evolutionary responses of populations to environmental changes requires a solid understanding of the spatial context in which they evolve. While the interplay between local adaptation and dispersal in guiding evolutionary outcomes has been studied extensively, it is often in a context of divergent selection and simplified spatial structure. Alternatively, we used a spatially‐explicit demo‐genetic agent‐based model to simulate a complex network of interconnected populations of Atlantic salmon facing a perturbation shifting their genetic composition to create diversity among populations. Our model allowed us to track emerging demographic, phenotypic, and evolutionary changes from the individual to the metapopulation in a single, spatially realistic framework. We analyzed the influence of the spatial structure of genetic diversity and populations on the evolutionary dynamics under convergent selection (toward a common optimum). Our simulations showed adaptation and demographic recovery of local populations was enhanced by dispersal between initially diverse populations, providing general support for the adaptation network theory. This was particularly true for increased dispersal rates and a random spatial genetic structure. Importantly, our spatially realistic model emphasized that the evolutionary and demographic trajectories of local populations are context‐dependent and can be heavily influenced by the spatial configuration of populations linked by dispersal. Overall, the adaptive capacity of the network depended on the 'opportunity for adaptation' provided by immigration patterns that emerged from the connectivity structures of the scenarios tested. We highlight the importance of spatial diversity and population structure for the ability of species to respond to environmental change, with implications for management and conservation of spatially structured populations. [ABSTRACT FROM AUTHOR]