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Perceptual learning is the process by which experience alters how incoming sensory information is processed by the brain to give rise to behavior—it is critical for how humans educate children, train experts, treat diseases, and promote health and well-being throughout the lifespan. Knowledge of perceptual learning requires basic and applied research in humans and nonhuman animal models, which informs strategic targets for advancing applications. Commercial products to induce perceptual learning are proliferating rapidly with limited regulation (e.g., for rehabilitation), while at the same time basic science is increasingly restricted by changing regulations (such as new granting-agency definitions of clinical trials). Realizing the full potential of perceptual learning requires balancing basic and translational science to advance new knowledge, while serving and protecting consumers. Reforms can promote open, accessible, and representative research, and the translation of this research to applications across different sectors of society.

Interest is growing in developing conservation strategies to restore and maintain coral reef ecosystems in the face of mounting anthropogenic stressors, particularly climate warming and associated mass bleaching events. One such approach is to propagate coral colonies ex situ and transplant them to degraded reef areas to augment habitat for reef-dependent fauna, prevent colonization from spatial competitors, and enhance coral reproductive output. In addition to such demographic restoration efforts, manipulating the thermal tolerance of outplanted colonies through assisted relocation, selective breeding, or genetic engineering is being considered for enhancing rates of evolutionary adaptation to warming. Although research into such assisted evolution strategies has been growing, their expected performance remains unclear. We evaluated the potential outcomes of demographic restoration and assisted evolution in climate change scenarios using an eco-evolutionary simulation model. We found that supplementing reefs with pre-existing genotypes (demographic restoration) offers little climate resilience benefits unless input levels are large and maintained for centuries. Supplementation with thermally resistant colonies was successful at improving coral cover at lower input levels, but only if maintained for at least a century. Overall, we found that, although demographic restoration and assisted evolution have the potential to improve long-term coral cover, both approaches had a limited impact in preventing severe declines under climate change scenarios. Conversely, with sufficient natural genetic variance and time, corals could readily adapt to warming temperatures, suggesting that restoration approaches focused on building genetic variance may outperform those based solely on introducing heat-tolerant genotypes.

Corals are experiencing unprecedented decline from climate change-induced mass bleaching events. Dispersal not only contributes to coral reef persistence through demographic rescue but can also hinder or facilitate evolutionary adaptation. Locations of reefs that are likely to survive future warming therefore remain largely unknown, particularly within the context of both ecological and evolutionary processes across complex seascapes that differ in temperature range, strength of connectivity, network size, and other characteristics. Here, we used eco-evolutionary simulations to examine coral adaptation to warming across reef networks in the Caribbean, the Southwest Pacific, and the Coral Triangle. We assessed the factors associated with coral persistence in multiple reef systems to understand which results are general and which are sensitive to particular geographic contexts. We found that evolution can be critical in preventing extinction and facilitating the long-term recovery of coral communities in all regions. Furthermore, the strength of immigration to a reef (destination strength) and current sea surface temperature robustly predicted reef persistence across all reef networks and across temperature projections. However, we found higher initial coral cover, slower recovery, and more evolutionary lag in the Coral Triangle, which has a greater number of reefs and more larval settlement than the other regions. We also found the lowest projected future coral cover in the Caribbean. These findings suggest that coral reef persistence depends on ecology, evolution, and habitat network characteristics, and that, under an emissions stabilization scenario (RCP 4.5), recovery may be possible over multiple centuries.

Global environmental change is challenging species with novel conditions, such that demographic and evolutionary trajectories of populations are often shaped by the exchange of organisms and alleles across landscapes. Current ecological theory predicts that random networks with dispersal shortcuts connecting distant sites can promote persistence when there is no capacity for evolution. Here, we show with an eco-evolutionary model that dispersal shortcuts across environmental gradients instead hinder persistence for populations that can evolve because long-distance migrants bring extreme trait values that are often maladaptive, short-circuiting the adaptive response of populations to directional change. Our results demonstrate that incorporating evolution and environmental heterogeneity fundamentally alters theoretical predictions regarding persistence in ecological networks.

Hue-scaling functions are designed to characterize color appearance by assessing the relative strength of the red versus green and blue versus yellow opponent sensations comprising different hues. However, these judgments can be non-intuitive and may pose difficulties for measurement and analysis. We explored an alternative scaling method based on positioning a dial to represent the relative similarity or distance of each hue from the labeled positions for the opponent categories. The hue-scaling and hue-similarity rating methods were compared for 28 observers. Settings on both tasks were comparable though the similarity ratings showed less inter-observer variability and weaker categorical bias, suggesting that these categorical biases may reflect properties of the task rather than the percepts. Alternatively, properties that are concordant for the two paradigms provide evidence for characteristics that do reflect color appearance. Individual differences on both tasks suggest that color appearance depends on multiple, narrowly tuned color processes, which are inconsistent with conventional color-opponent theory.

Vegetation structural complexity surrounding nests can either provide concealment for intruders and mates or make it more difficult for hosts to recognize parasitic eggs. We investigated whether shading and vegetation aggregation increase extrapair paternity (the presence of broods with half‐siblings) and intraspecific brood parasitism (IBP, the occurrence of broods with unrelated offspring) in socially monogamous Blue‐black Grassquits Volatinia jacarina. We found that habitat shadowing was associated with increased occurrence of IBP, but found no association between the degree of shade and the presence of extrapair offspring. Our findings support the idea that habitat limits cryptic reproductive behaviours and that female grassquits may benefit from habitat shadows to parasitize conspecific nests. [ABSTRACT FROM AUTHOR]

Group‐living in animals comes with a number of benefits associated with predator avoidance, foraging, and reproduction. A large proportion of fish species display grouping behaviour. Fish may also be particularly vulnerable to climate‐related stressors including thermal variation, hypoxia, and acidification. As climate‐related stressors are expected to increase in magnitude and frequency, any effects on fish behaviour may be increased and affect the ability of fish species to cope with changing conditions. Here we conduct a systematic review of the effects of temperature, hypoxia, and acidification on individual sociability and group cohesion in shoaling and schooling fishes. Searches of the published and grey literature were carried out, and studies were included or excluded based on selection criteria. Data from studies were then included in a meta‐analysis to examine broad patterns of effects of climate‐related stressors in the literature. Evidence was found for a reduction in group cohesion at low oxygen levels, which was stronger in smaller groups. While several studies reported effects of temperature and acidification, there was no consistent effect of either stressor on sociability or cohesion. There was some evidence that marine fishes are more strongly negatively affected by acidification compared with freshwater species, but results are similarly inconsistent and more studies are required. Additional studies of two or more stressors in combination are also needed, although one study found reduced sociability following exposure to acidification and high temperatures. Overall, there is some evidence that hypoxia, and potentially other climate‐related environmental changes, impact sociability and group cohesion in fishes. This may reduce survival and adaptability in shoaling and schooling species and have further ecological implications for aquatic systems. However, this synthesis mainly highlights the need for more empirical studies examining the effects of climate‐related factors on social behaviour in fishes. [ABSTRACT FROM AUTHOR]

We examined how visual sensitivity and perception are affected by adaptation to the characteristic amplitude spectra of X-ray mammography images. Because of the transmissive nature of X-ray photons, these images have relatively more low-frequency variability than natural images, a difference that is captured by a steeper slope of the amplitude spectrum (~ - 1.5) compared to the ~ 1/f (slope of - 1) spectra common to natural scenes. Radiologists inspecting these images are therefore exposed to a different balance of spectral components, and we measured how this exposure might alter spatial vision. Observers (who were not radiologists) were adapted to images of normal mammograms or the same images sharpened by filtering the amplitude spectra to shallower slopes. Prior adaptation to the original mammograms significantly biased judgments of image focus relative to the sharpened images, demonstrating that the images are sufficient to induce substantial after-effects. The adaptation also induced strong losses in threshold contrast sensitivity that were selective for lower spatial frequencies, though these losses were very similar to the threshold changes induced by the sharpened images. Visual search for targets (Gaussian blobs) added to the images was also not differentially affected by adaptation to the original or sharper images. These results complement our previous studies examining how observers adapt to the textural properties or phase spectra of mammograms. Like the phase spectrum, adaptation to the amplitude spectrum of mammograms alters spatial sensitivity and visual judgments about the images. However, unlike the phase spectrum, adaptation to the amplitude spectra did not confer a selective performance advantage relative to more natural spectra.

Resolving the degree to which environmental (direct) versus genetic (indirect) benefits shape female mate choice is a long-standing challenge, particularly for socially monogamous species where male environmental and genetic contributions are difficult to disentangle. This study combines long-term population monitoring with quantitative genetic analyses in a socially monogamous but sexually promiscuous Australian songbird to demonstrate that female mating preferences are driven by nongenetic environmental benefits that increase the fitness of both the female and her offspring. Male Red-backed Fairywrens (Malurus melanocephalus) flexibly breed in either ornamented or unornamented plumage, and females consistently prefer ornamented males. Females paired with ornamented males bred earlier and allocated more to current reproduction yet experienced higher survival and lifetime fitness. Furthermore, these females produced more grand-offspring because their early-born sons were more likely to be ornamented and to breed successfully than the later-born sons of females with unornamented partners. Quantitative genetic models showed lifetime fitness was best explained by parental environment rather than genetic effects. Mating preferences in this system are maintained by a combination of primary environmental benefits that increase the lifetime fitness of choosy females and secondary environmental benefits that increase the multigenerational fitness of those females through enhanced offspring quality and performance. [ABSTRACT FROM AUTHOR]

Individual differences are a prominent feature of normal color vision and range from variations in sensitivity to perception and color naming. Corrections for differences in spectral sensitivity are common, and there is growing interest in calibrating displays for the sensitivity of an individual observer. In contrast, few studies have explored calibrations for aspects of color appearance. We developed a technique for adjusting images based directly on an individual's hue percepts and illustrate the principle of the approach using a set of hue scaling functions measured previously for a large sample of color‐normal observers (Emery et al. PNAS 2023). Colors in an image are mapped onto the average scaling function to define the hue perceived by the average “standard observer.” This hue is then mapped back to the chromaticity that would elicit the same response in any individual observer. With this correction, different observers – each looking at physically different images calibrated for their own hue percepts – should in principle agree on the perceived colors. Adjustments of this kind could be easily implemented on standard displays, because they require only measures of hue percepts and not spectral sensitivity, and could lead to greater consistency in the perception and communication about color across individuals with potentially widely different perceptual experiences of color. [ABSTRACT FROM AUTHOR]

Over the past century, the Javan rhinoceroses' (Rhinoceros sondaicus) secluded nature and low population size have led to a gap in knowledge of their ecology. With fewer than 80 individuals surviving in a single population in West Java, Indonesia, the Javan rhinoceros is one of the most critically endangered mammals in the world. As part of a pilot bioacoustics study of the Javan rhinoceros in 2019, we systematically reviewed camera trap footage from the core Javan rhinoceros range in Ujung Kulon National Park (UKNP). In doing so, we discovered a previously unknown interaction between the Javan rhinoceros and the slender‐billed crow (Corvus enca), in which the crow finds and eats ectoparasites from the rhinoceros (Figure 1). We describe this interaction and suggest that it may represent a cleaning mutualism with benefits for both the crow and the rhinoceros. [ABSTRACT FROM AUTHOR]