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During social interactions, the behavior of an individual often depends on the sex of its social partner. Many animal societies have males and females that play very different behavioral roles, although they coexist and interact non-sexually. At specific phases of the colony cycle, social wasp females and males are contemporaries within a nest, they often interact, although mating occurs mostly off the nest, therefore providing an opportunity to test sex discrimination in contexts other than classical sexual ones. We performed a lure presentation experiment to test if Mischocyttarus metathoracicus discriminate between conspecifics of the 2 sexes during on-nest social interactions. Female wasps discriminated conspecific sex during experimentally simulated nest intrusions. Visual and chemical cues may account for this sex discrimination. Despite sex discrimination (evidenced by differential inspective behavior from the nest females toward the female and the male lures), female wasps were as aggressive toward lures of both sexes. In the female-dominated hymenopteran societies, males are often subordinate and not aggressive on nest, resulting in females directing less aggression to them compared to other females. Instead, M. metathoracicus males and females are both aggressive toward nestmates, so they might be perceived as similar threat during on-nest social interactions.

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Small-scale fisheries are vital for food security, nutrition, and livelihoods in coastal areas throughout the world's oceans.1-9 As intricately linked social-ecological systems, small-scale fisheries require management approaches that help ensure both ecological and socioeconomic sustainability.7,10-14 Given their ease of use and lucrative nature, coastal gillnet fisheries are globally ubiquitous.10,15 However, these fisheries often result in high discarded capture of non-target organisms (bycatch) that can lead to significant cascading effects throughout trophic chains16-18 and costly fisheries restrictions that result in important revenue losses in coastal communities with scarce economic alternatives.19,20 Despite these challenges, few solutions have been developed and broadly adopted to decrease bycatch in coastal gillnet fisheries, particularly in developing nations.5,21 Here we used controlled experiments along Mexico's Baja California peninsula to show that illuminating gillnets with green LED lights-an emerging technology originally developed to mitigate sea turtle bycatch-significantly reduced mean rates of total discarded bycatch biomass by 63%, which included significant decreases in elasmobranch (95%), Humboldt squid (81%), and unwanted finfish (48%). Moreover, illuminated nets significantly reduced the mean time required to retrieve and disentangle nets by 57%. In contrast, there were no significant differences in target fish catch or value. These findings advance our understanding of how artificial illumination affects operational efficiency and changes in catch rates in coastal gillnet fisheries, while illustrating the value of assessing broad-scale ecological and socioeconomic effects of species-specific conservation strategies.

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Introduction: Number sense has been systematically measured using dot comparison tasks. However, recent studies have reported that performance on dot comparison might be influenced inhibitory control and visual properties of dot arrays. In the present study, we analysed the influence of continuous magnitude, inhibitory control, and numerical ratio on the dot comparison performance of preschool children. Methods: Participants were 517 preschool children from 13 different schools in Chile. Children completed a dot comparison and two inhibitory control tasks. Gebuis and Reynvoet method was used to create well-controlled dot arrays for use in the dot comparison task. A logistic mixed effects model was conducted to predict participants' dot comparison accuracy. Continuous magnitude and ratio were entered as level-1 predictors and inhibitory control as level-2 predictors. Results: The results showed that all predictors made a significant contribution to dot comparison accuracy. Furthermore, a significant double interaction (inhibitory control x continuous magnitude) and a triple interaction (inhibitory control x continuous magnitude x ratio) showed that the contribution of inhibitory control skills in dot comparison accuracy depends on the continuous properties of dot arrays and ratio. Discussion: These findings suggest that preschool children rely more on continuous magnitudes than numerosity in dot comparison tasks. They also indicate that the greater children's inhibitory control, the more able they are to respond based on numerosity in fully incongruent trials, particularly when ratio is low (easiest items). Taken together, the above findings support the competing processes account provided that both ANS and inhibitory control skills influence performance on dot comparison tasks.

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BACKGROUND: Learning abilities help animals modify their behaviors based on experience and innate sensory biases to confront environmental unpredictability. In a food acquisition context, the ability to detect, learn, and switch is fundamental in a wide range of insect species facing the ever-changing availability of their floral rewards. Here, we used an experimental approach to address the innate color preferences and learning abilities of the common green-eyed white butterfly (Leptophobia aripa). METHODS: In Experiment 1, we conducted innate preference choice-tests to determine whether butterflies had a strong innate color preference and to evaluate whether color preferences differed depending on the array of colors offered. We faced naïve butterflies to artificial flowers of four colors (quadruple choice-test): yellow, pink, white, and red; their choices were assessed. In Experiment 2, we examined the ability of this butterfly species to associate colors with rewards while exploring if the spectral reflectance value of a flower color can slow or accelerate this behavioral response. Butterflies were first trained to be fed from artificial yellow flowers inserted in a feeder. These were later replaced by artificial flowers with a similar (blue) or very different (white) spectral reflectance range. Each preference test comprised a dual-choice test (yellow vs blue, yellow vs white). RESULTS: Butterflies showed an innate strong preference for red flowers. Both the number of visits and the time spent probing these flowers were much greater than the pink, white, and yellow color flowers. Butterflies learn to associate colors with sugar rewards. They then learned the newly rewarded colors as quickly and proficiently as if the previously rewarded color was similar in spectral reflectance value; the opposite occurs if the newly rewarded color is very different than the previously rewarded color. CONCLUSIONS: Our findings suggest that common green-eyed white butterflies have good learning abilities. These capabilities may allow them to respond rapidly to different color stimulus.

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Biotic and abiotic factors may individually or interactively disrupt plant-pollinator interactions, influencing plant fitness. Although variations in temperature and precipitation are expected to modify the overall impact of predators on plant-pollinator interactions, few empirical studies have assessed if these weather conditions influence anti-predator behaviors and how this context-dependent response may cascade down to plant fitness. To answer this question, we manipulated predation risk (using artificial spiders) in different years to investigate how natural variation in temperature and precipitation may affect diversity (richness and composition) and behavioral (visitation) responses of flower-visiting insects to predation risk, and how these effects influence plant fitness. Our findings indicate that predation risk and an increase in precipitation independently reduced plant fitness (i.e., seed set) by decreasing flower visitation. Predation risk reduced pollinator visitation and richness, and altered species composition of pollinators. Additionally, an increase in precipitation was associated with lower flower visitation and pollinator richness but did not alter pollinator species composition. However, maximum daily temperature did not affect any component of the pollinator assemblage or plant fitness. Our results indicate that biotic and abiotic drivers have different impacts on pollinator behavior and diversity with consequences for plant fitness components. Even small variation in precipitation conditions promotes complex and substantial cascading effects on plants by affecting both pollinator communities and the outcome of plant-pollinator interactions. Tropical communities are expected to be highly susceptible to climatic changes, and these changes may have drastic consequences for biotic interactions in the tropics.

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The postural control is improved by implicit somatosensory information from lightly touching a rigid bar or explicit visual information about the postural sway. Whether these two additional sources provided at the same time further reduce the postural sway is still unknown. Participants stood on a force plate as quiet as possible lightly touching the bar while received or not visual feedback of the center of pressure position on a monitor screen. Postural sway reduced similarly with the light touch regardless of the additional visual feedback. The findings suggested that providing explicit visual feedback of the center of pressure does not increase the light touch effects on the postural sway. The importance of the implicit somatosensory information on postural control is discussed.

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Resumen El objetivo del estudio es cuantificar el efecto de la información situacional probabilística (ISP) sobre el rendimiento deportivo y en concreto sobre el inicio en el tiempo de respuesta y la precisión de los deportistas. Existe evidencia científica de que los deportistas de mayor nivel deportivo desarrollan la habilidad perceptiva para usar la ISP, realizando comportamientos anticipatorios, si bien se desconoce la magnitud de dicho efecto. Se realiza un metaanálisis de efectos aleatorios para cuantificar el tamaño del efecto (TE) de la ISP en el comportamiento motor de los deportistas. Los resultados muestran un TE medio final grande de 1.29 para el tiempo de respuesta (en 7 estudios y 252 participantes) y de 1.31 para la precisión (en nueve investigaciones y 292 participantes), seleccionados de acuerdo con los criterios establecidos. Con la limitación del reducido número de estudios analizados (n = 9), los resultados indican que los deportistas expertos anticipan más respuestas y con más precisión que los noveles debido al uso de la ISP. Se recomienda entrenar perceptivamente la identificación y el uso de la ISP a nivel deportivo, ya que aquellos deportistas que hagan un mejor uso de esta información contextual podrán anticipar sus respuestas con precisión.

Abstract The aim of the study is to quantify the effect of Situational Probability Information (SPI) on athletic performance, specifically on the onset of the response time and the accuracy of athletes. There is scientific evidence that shows that higher sport level athletes develop the perceptive skills to use SPI, thereby performing anticipatory behaviors. However, the magnitude of this effect remains unknown. A meta-analysis of random effects was carried out to quantify the effect size (ES) of SPI on the motor behavior of athletes. The results showed an overall final mean ES of 1.29 for the response time (in 7 studies and 252 participants), and 1.31 for accuracy (in 9 studies and 292 participants), according to the criteria established. With the limitation of the low number of studies analyzed (n = 9), the results suggest that expert athletes anticipate more frequently and with higher accuracy than beginners, due to the use of SPI. It is recommended to train in the identification and use of the SPI in the sports domain, as athletes who use this contextual information more effectively could anticipate the responses with precision.

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OBJECTIVE: The aim of this study is to investigate the effects of transcranial direct current stimulation (tDCS) combined with cueing gait training (CGT) on functional mobility in patients with Parkinson´s disease (PD). METHODS: A pilot double-blind controlled, randomized clinical trial was conducted with 22 patients with PD assigned to the experimental (anodal tDCS plus CGT) and control group (sham tDCS plus CGT). The primary outcome (functional mobility) was assessed by 10-m walk test, cadence, stride length, and Timed Up and Go test. Motor impairment, bradykinesia, balance, and quality of life were analyzed as secondary outcomes. Minimal clinically important differences (MCIDs) were observed when assessing outcome data. RESULTS: Both groups demonstrated similar gains in all outcome measures, except for the stride length. The number of participants who showed MCID was similar between groups. CONCLUSION: The CGT provided many benefits to functional mobility, motor impairment, bradykinesia, balance, and quality of life. However, these effect magnitudes were not influenced by stimulation, but tDCS seems to prolong the effects of cueing therapy on functional mobility.

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Mainly owing to their high diversity and abundance, ants are formidable as predators and defenders of foliage. Consequently, ants can exclude both invertebrate and vertebrate activity on plants via direct and indirect interactions as already shown in many previous studies. Here we present empirical evidence that objects resembling ant shape on dummy caterpillars were able to repel visually oriented predators. Moreover, we also show that rubber ants on dummy fruits can repel potential fruit dispersers. Our results have direct implications on the ecological and evolutionary dynamics of interactions in ant-based systems, as ant presence could affect the fitness of its partners. In short, our study highlights the importance of visual cues in interspecific interactions and opens a new way to study the effects of ant presence to test ecological and evolutionary hypotheses.

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This study investigated the ability of the dusky damselfish Stegastes fuscus to associate conditioned and unconditioned stimuli (single CS-US) and to find a specific place in a clueless ambiece (spatial learning). After tested for colour preference and showing no specific colour attractively, the fish were trained to associate a colour cue with a stimulus fish (conspecific). Fish were then challenged to locate the exact place where the stimulus fish was presented. Stegastes fuscus spent most time close to the zone where stimulus was presented, even without obvious marks for orientation. The results confirm that S. fuscus show single CS-US learning and suggest the fish ability for spatial orientation. Stegastes fuscus appears to use multiple senses (sight and lateral line) for cues association and recall, and appear to perform relational learning similar to mammals. These data suggest the importance of cognitive skill for reef fishes that may have contributed to their establishment and evolutionary success in such complex environment.

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The arboreal ant Odontomachus hastatus nests among roots of epiphytic bromeliads in the sandy forest at Cardoso Island (Brazil). Crepuscular and nocturnal foragers travel up to 8m to search for arthropod prey in the canopy, where silhouettes of leaves and branches potentially provide directional information. We investigated the relevance of visual cues (canopy, horizon patterns) during navigation in O. hastatus. Laboratory experiments using a captive ant colony and a round foraging arena revealed that an artificial canopy pattern above the ants and horizon visual marks are effective orientation cues for homing O. hastatus. On the other hand, foragers that were only given a tridimensional landmark (cylinder) or chemical marks were unable to home correctly. Navigation by visual cues in O. hastatus is in accordance with other diurnal arboreal ants. Nocturnal luminosity (moon, stars) is apparently sufficient to produce contrasting silhouettes from the canopy and surrounding vegetation, thus providing orientation cues. Contrary to the plain floor of the round arena, chemical cues may be important for marking bifurcated arboreal routes. This experimental demonstration of the use of visual cues by a predominantly nocturnal arboreal ant provides important information for comparative studies on the evolution of spatial orientation behavior in ants. "This article is part of a Special Issue entitled: Neotropical Behaviour".

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Las expresiones emocionales tienen un papel fundamental en las interacciones de especies sociales, brindando información acerca del emisor, las características e importancia del estímulo o situación que desencadena tales interacciones, y también funcionan regulando los vínculos sociales. Los perros poseen notorias capacidades comunicativas hacia los humanos por lo que resulta interesante estudiar si estas habilidades se extienden al reconocimiento de las expresiones emocionales. Se han realizado diversas investigaciones acerca del reconocimiento de expresiones emocionales humanas en perros exponiéndolos a una situación representada por personas durante la evaluación, así como mediante el uso de imágenes, videos y grabaciones. El análisis de las evidencias permite concluir que los perros podrían distinguir entre distintas emociones humanas ya sea en presencia de modelos en vivo o mediante la observación de imágenes y modulan su conducta conforme esta discriminación, así como también pueden utilizar esta información como clave en la resolución de problemas. Sin embargo, aún no están claros los mecanismos que subyacen a estas habilidades.(AU)

Emotional expressions play a critical role in the interactions among individuals, particularly, in social species. They provide information about the sender and the characteristics and importance of the triggering stimulus or situation, also regulating social ties. Dogs have notorious communication skills towards humans, which makes the study of their ability to recognize human emotional expressions an interesting endeavor. There have been several studies in which dogs have been tested using real people in an experimental situation as well as images, video and audio recordings of people's expressions. The evidence suggests that dogs can discriminate between different human emotions either in the presence of live models or by looking at images. This type of information has been shown to modulate their behavior and to be used as cues to solve problems. However, the mechanisms underlying these abilities are not fully understood yet.(AU)

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Las expresiones emocionales tienen un papel fundamental en las interacciones de especies sociales, brindando información acerca del emisor, las características e importancia del estímulo o situación que desencadena tales interacciones, y también funcionan regulando los vínculos sociales. Los perros poseen notorias capacidades comunicativas hacia los humanos por lo que resulta interesante estudiar si estas habilidades se extienden al reconocimiento de las expresiones emocionales. Se han realizado diversas investigaciones acerca del reconocimiento de expresiones emocionales humanas en perros exponiéndolos a una situación representada por personas durante la evaluación, así como mediante el uso de imágenes, videos y grabaciones. El análisis de las evidencias permite concluir que los perros podrían distinguir entre distintas emociones humanas ya sea en presencia de modelos en vivo o mediante la observación de imágenes y modulan su conducta conforme esta discriminación, así como también pueden utilizar esta información como clave en la resolución de problemas. Sin embargo, aún no están claros los mecanismos que subyacen a estas habilidades.

Emotional expressions play a critical role in the interactions among individuals, particularly, in social species. They provide information about the sender and the characteristics and importance of the triggering stimulus or situation, also regulating social ties. Dogs have notorious communication skills towards humans, which makes the study of their ability to recognize human emotional expressions an interesting endeavor. There have been several studies in which dogs have been tested using real people in an experimental situation as well as images, video and audio recordings of people's expressions. The evidence suggests that dogs can discriminate between different human emotions either in the presence of live models or by looking at images. This type of information has been shown to modulate their behavior and to be used as cues to solve problems. However, the mechanisms underlying these abilities are not fully understood yet.

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OBJECTIVE: The goal of this study was to investigate whether on-topic visual cues can serve as aids for the maintenance of discourse coherence and informativeness in autobiographical narratives of persons with Alzheimer's disease (AD). METHODS: The experiment consisted of three randomized conversation conditions: one without prompts, showing a blank computer screen; an on-topic condition, showing a picture and a sentence about the conversation; and an off-topic condition, showing a picture and a sentence which were unrelated to the conversation. Speech was recorded while visual attention was examined using eye tracking to measure how long participants looked at cues and the face of the listener. RESULTS: Results suggest that interventions using visual cues in the form of images and written information are useful to improve discourse informativeness in AD. CONCLUSION: This study demonstrated the potential of using images and short written messages as means of compensating for the cognitive deficits which underlie uninformative discourse in AD. Future studies should further investigate the efficacy of language interventions based in the use of these compensation strategies for AD patients and their family members and friends.

OBJETIVO: O objetivo deste estudo foi o de investigar se pistas visuais sobre o tópico discursivo podem servir como auxiliares para a manutenção da coerência e da informatividade em narrativas autobiográficas de pessoas com doença de Alzheimer (DA). MÉTODOS: O experimento apresentou três condições: uma conversa tendo à vista uma tela de computador em branco; uma condição de conversação com pista dentro do tópico, em que a tela do computador mostrava uma foto e uma frase sobre o evento tema; e uma condição fora de tópico, em que a tela mostrava uma foto e uma frase que não apresentavam relação com o tema da conversa. O discurso foi gravado enquanto a atenção visual foi examinada através de rastreamento ocular para medir a atenção dos participantes para as pistas apresentadas na tela e para o rosto do ouvinte. RESULTADOS: Os resultados sugerem que as intervenções por meio de pistas visuais na forma de imagens e informações escritas são úteis para melhorar a informatividade discursiva na AD. CONCLUSÃO: Este estudo demonstrou o potencial do uso de imagens e mensagens escritas curtas como meios de compensação para aumentar a informatividade do discurso em pacientes com DA. Estudos futuros devem investigar a eficácia de intervenções de linguagem baseadas no uso dessas estratégias de compensação para a comunicação de pacientes com DA com seus familiares e amigos.

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Reproductive fish behavior is affected by male-female interactions that stimulate physiological responses such as hormonal release and gonad development. During male-female interactions, visual and chemical communication can modulate fish reproduction. The aim of the present study was to test the effect of visual and chemical male-female interaction on the gonad development and reproductive behavior of the cichlid fish Nile tilapia, Oreochromis niloticus (L.). Fifty-six pairs were studied after being maintained for 5 days under one of the four conditions (N = 14 for each condition): 1) visual contact (V); 2) chemical contact (Ch); 3) chemical and visual contact (Ch+V); 4) no sensory contact (Iso) - males and females isolated. We compared the reproductive behavior (nesting, courtship and spawning) and gonadosomatic index (GSI) of pairs of fish under all four conditions. Visual communication enhanced the frequency of courtship in males (mean ± SEM; V: 24.79 ± 3.30, Ch+V: 20.74 ± 3.09, Ch: 0.1 ± 0.07, Iso: 4.68 ± 1.26 events/30 min; P < 0.05, two-way ANOVA with LSD post hoc test), induced spawning in females (3 spawning in V and also 3 in Ch+V condition), and increased GSI in males (mean ± SEM; V: 1.39 ± 0.08, Ch+V: 1.21 ± 0.08, Ch: 1.04 ± 0.07, Iso: 0.82 ± 0.07 percent; P < 0.05, two-way ANOVA with LSD post hoc test). Chemical communication did not affect the reproductive behavior of pairs nor did it enhance the effects of visual contact. Therefore, male-female visual communication is an effective cue, which stimulates reproduction among pairs of Nile tilapia.

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