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Alcohol and nicotine are psychoactive substances responsible for serious health consequences. Although the biological mechanisms of alcohol and nicotine have been studied extensively, individual differences in the response to these drugs have received little attention. Here we evaluated gene expression and behavior of bold and shy individuals after acute exposure to alcohol and nicotine. For this, zebrafish were classified as bold and shy individuals based on emergence tests, and then fish were exposed to 0.00, 0.10, and 0.50% alcohol or 0.00, 1.00, and 5.00 mg/L nicotine and their anxiety-like and locomotor behavior was observed. After behavioral assessment, brain mRNA expression (ache, bdnf, gaba1, gad1b, th1, and tph1) was evaluated. Locomotion patterns differed between profiles depending on alcohol and nicotine concentration. Anxiety increased in shy fish and decreased in bold fish after exposure to both drugs. Alcohol exposure induced an increase in tph1 mRNA expression in bold fish, while bdnf mRNA expression was increased in shy fish. Nicotine increased ache, bdnf, and tph1 mRNA levels in both profiles, but at higher levels in bold fish. Based on our research, we found that alcohol induces anxiogenic effects in both bold and shy zebrafish. Additionally, shy individuals exposed to a low concentration of nicotine exhibited stronger anxiety-like responses than their bold counterparts. These findings further support the validity of using zebrafish as a dependable tool for studying the effects of drugs and uncovering the underlying mechanisms associated with individual variations.

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Individuals differ in their preference for alcohol and propensity to develop alcoholism, where the behavioral profile, such as the bold-shy axis, plays an important role for such a difference. However, literature is limited and conflicting on the causes and consequences of this relationship. Translational studies using animal models, such as zebrafish, can help identify behavioral traits that predispose individuals to drink alcohol compulsively. Here, the preference for alcohol was investigated in two distinct traits in zebrafish: shy and bold. For this purpose, fish were separated into shy and bold traits and then a conditioned place preference paradigm was used, a strategy that allows the rewarding effects from alcohol to be assessed by the ability to enhance the animal's preference for an environment that initially was not preferred. It was found that bold zebrafish actively searched for the environment that was paired to alcohol after one acute exposure, whereas, shy fish changed their place preference even without alcohol administration, showing that the conditioned place preference protocol, given the short amount time to assess place preference, is not ample enough for shy fish to choose. Our results show that behavioral profiles must be considered in further studies since differences between shy and bold individuals on preference behavior can strongly interfere in the assessment of drug preference, mainly when using the conditioned place preference paradigm.

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The number of animal species threatened with extinction are increasing every year, and biologists are conducting animal translocations, as one strategy, to try to mitigate this situation. Furthermore, researchers are evaluating methods to increase translocation success, and one area that shows promise is the study of animal personality. Animal personality can be defined as behavioral and physiological differences between individuals of the same species, which are stable in time and across different contexts. In the present paper, we discuss how animal personality can increase the success of translocation, as well as in the management of animals intended for translocation by evaluating personality characteristics of the individuals. Studies of the influence of birthplace, parental behavior, stress resilience, and risk assessment can be important to select the most appropriate individuals to be released. Finally, we explain the two methods used to gather personality data.

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Wildfires are a common phenomenon in Mediterranean regions that is becoming increasingly frequent and severe, causing several environmental concerns, of which ash runoff represents an important source of disturbance for aquatic organisms, in particular for fishes. Studies on the behavioural response of fishes to wildfire ash runoff are scarce and seldom include cyprinid species. The goal of this study was to investigate in a 3-artificial flume channel mesocosm, the behavioural and hepatosomatic condition responses of a native widespread potamodromous fish, the Iberian barbel (Luciobarbus bocagei), previously exposed for 24 h to different concentrations of wildfire ashes: 0.0 g/L (the control, no ash), 1.0 g/L (low concentration) and 2.0 g/L (high concentration). Behavioural parameters included i) routine activity, ii) boldness and iii) shoaling cohesion. The hepatosomatic index (HSI) was further determined to assess the health condition of fish. Significant differences on fish behaviour parameters were detected between the control and the high concentration of ash. Accordingly, i) an increasing proportion of fish were found on resting activity (56.2% vs 30.6% in the control), whereas the proportion of fish on searching behaviour (58.4% in the control) decreased (41.5%); ii) the proportion of bolder individuals was found to decrease (42.5% in the control vs. 29.4%) and iii) the same trend was detected for shoaling cohesion (61.3% in the control to 33.8%, of all fish within a body length of each other). Such differences were paralleled by an increase in the HSI from 1.62% (control) to 2.40% (high concentration). The present study shows that even short duration exposure to ash-loaded runoff can alter fish behaviour and hepatosomatic condition and highlights the need to maintain an unfragmented river network, or, when this is not possible, to prioritize the removal or retrofitting of barriers to increase movement dispersal and provide conditions for species recovery from fire-disturbances.

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Urban environments are rapidly expanding and presenting animal populations with novel challenges, many of which are thought to be stressors that contribute to low biodiversity. However, studies on stress responses in urban vs rural populations have produced mixed results, and many of these studies use a standard stressor that cannot be replicated in the wild (e.g. restraining an animal in a bag). Pairing physiological and behavioral measurements in response to urban-related stressors improves our understanding of the mechanism underlying animal success in human-dominated landscapes. Here, we examined the physiological stress (plasma corticosterone, CORT) responses of a songbird species (the house finch, Haemorhous mexicanus) to two different anthropogenic stimuli - (1) the presence of a human and (2) a captive environment containing man-made objects. During three field seasons (summer 2012, winter 2014, and winter 2015), we captured birds at six sites along an urban gradient in Phoenix, Arizona, USA and measured plasma CORT levels both before and after each trial. Though CORT levels did increase post-human exposure, though not during exposure to novel environment, indicating only one of the treatments caused a physiological response, baseline or post-trial plasma CORT levels did not differ between finches between urban and rural birds in 2012 or 2014. However, rural birds demonstrated relatively low pre- and post-trial plasma CORT levels during the human-exposure trials in 2015. Furthermore, we found few correlations between behavioral and physiological responses. A significant positive correlation was only detected between activity behavior after human approach and post-trial plasma CORT levels in 2012. Taken together, our results reveal a weak, conditional relationship between stress physiology, behavioral responses, and urbanization in house finches.

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Considering that each personality type in animals presents distinct physiological and behavioural responses, this study evaluated the efficiency of the Novel Environment test to classify larvae of Lophiosilurus alexandri into bold and shy individuals, which were then investigated for growth, cannibalism and mortality in larviculture of pure and mixed groups. Larvae with an average weight of 24.0±1.7mg and length of 14.1±0.4mm, were subjected to a Novel Environment test to classify their personality type (bold and shy larvae). After the larvae were classified according to personality type, they were subjected to larviculture for 15days. Three treatments were tested: only bold larvae, only shy larvae, and a mixed treatment (bold larvae+shy larvae) at a density for 16 larvae/L, which were fed 3 times a day with Artemia nauplii. After larviculture, there were no differences in the final lengths of larvae of the bold, shy, and mixed treatments (26.9±0.76mm, 26.7±1.00mm, and 26.8±1.24mm, respectively); however, shy larvae possessed weighed less (0.22±0.01g) than the bold and mixed treatments, which did not differ significantly (0.25±0.02g and 0.27±0.02g, respectively). The bold and mixed treatments had the highest cannibalism rate (11.2±5.1% and 23.1±12.3%, respectively). Overall survival was lowest in the mixed treatment (62.5±13.0%), while that of the bold and shy treatments were similar (82.5±9.2% and 86.2±9.2%, respectively). The separation of L. alexandri larvae by traits can ensure a decrease in cannibalism and hence, more productive larviculture.

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Abstract:Predators can influence a variety of prey traits, including behavior. Traits such as boldness, activity rate, and tendency to explore can all be shaped by predation risk. Our study examines the effects of predation on these behaviors by considering a natural system in which two sister species of livebearing fishes, Brachyrhaphis roseni and B. terrabensis, experience divergent predation environments. In February of 2013, we collected fish in the Río Chiriquí Nuevo drainage, Chiriquí, Panama, and conducted behavioral assays. Using open-field behavioral assays, we evaluated both juveniles and adults, and males and females, to determine if there were differences in behavior between ontogenetic stages or between sexes. We assessed boldness as 'time to emerge' from a shelter into a novel environment, and subsequently measured activity and exploration within that novel environment. We predicted that B. roseni (a species that co-occurs with predators) would be more bold, more active, and more prone to explore, than B. terrabensis (a species that does not co-occur with predators). In total, we tested 17 juveniles, 21 adult males, and 20 adult females of B. roseni, and 19 juveniles, 19 adult males, and 18 adult females of B. terrabensis. We collected all animals from streams in Chiriquí, Panama in February 2013, and tested them following a short acclimation period to laboratory conditions. As predicted, we found that predation environment was associated with several differences in behavior. Both adult and juvenile B. roseni were more active and more prone to explore than B. terrabensis. However, we found no differences in boldness in either adults or juveniles. We also found a significant interaction between 'sex' and 'species' as predictors of boldness and exploration, indicating that predation environment can affect behaviors of males and females differently in each species. Our work demonstrates the importance of considering sex and life history stage when evaluating the evolution of behavior. Rev. Biol. Trop. 65 (1): 267-277. Epub 2017 March 01.

ResumenLos depredadores pueden influenciar una variedad de rasgos de la presa, incluyendo el comportamiento. Los rasgos tales como la audacia, nivel de actividad, y la tendencia a explorar; pueden ser moldeados por el riesgo de depredación. Nuestro estudio examina los efectos de la depredación en el comportamiento al considerar un sistema natural en el que dos especies hermanas de peces vivíparos, Brachyrhaphis roseni y B. terrabensis, se presentan en ambientes de depredación divergente. En febrero 2013, recolectamos peces en el drenaje del Río Chiriquí Nuevo, Chiriquí, Panamá y llevamos a cabo ensayos de comportamiento. Al usar ensayos de comportamiento en campo abierto, se evaluó el comportamiento en juveniles y adultos, machos y hembras, para determinar si los patrones de divergencia diferían entre las etapas ontogenéticas o entre sexos. Se evaluó la audacia como "tiempo en salir" de un refugio a un ambiente nuevo, y posteriormente se midió la actividad y la exploración dentro de ese nuevo ambiente. Nosotros predijimos que B. roseni (una especie que se presenta con los depredadores) sería más audaz, activa y propensa a explorar que B. terrabensis (una especie que no se presenta con los depredadores). En total, probamos 17 jóvenes, 21 machos adultos, y 20 hembras adultas de B. roseni, y 19 jóvenes, 19 machos adultos, y 18 hembras adultas de B. terrabensis. Recogimos todos los animales en Chiriquí, Panamá en Febrero 2013, y los probamos después de un corto período de aclimatación a las condiciones de laboratorio. Como se predijo, se encontró que la depredación ambiental se asoció con varias diferencias en el comportamiento. Tanto adultos y jóvenes de B. roseni eran más activos y más propensos a explorar que B. terrabensis. Sin embargo, no se encontraron diferencias en la audacia en adultos o menores. También se encontró una interacción significativa entre "sexo" y "especie" como predictores de la audacia y la exploración, lo que indica que la depredación puede afectar el comportamiento de los machos y hembras de manera diferente en cada especie. Nuestro estudio demuestra la importancia de considerar el sexo y la etapa del ciclo de vida al evaluar la evolución del comportamiento.

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O objetivo deste artigo é apresentar resultados da pesquisa qualitativa dos autoressobre autoliderança e assunção da singularidade consciencial, a fim de colaborar comas consciências interessadas no desenvolvimento da liderança de modo sadio e autoevolutivo.O artigo aborda autodesafios e benefícios no desenvolvimento da autoliderança,a partir da assunção da singularidade consciencial. O interesse pela pesquisasurgiu na identificação de crenças limitadoras observadas nos próprios autores e emoutros líderes. O método empregado foi a análise qualitativa das autovivências dosautores e de dezenas de casos observados em cursos, conscins-cobaias, debates, atendimentos,além de pesquisa bibliográfica e filmográfica. A partir da análise realizada,conclui-se que a adoção do estilo próprio de liderar e a assunção da singularidadeconsciencial são elementos indispensáveis ao desenvolvimento da autoliderançasadia. A conquista é mensurável pelos resultados evolutivos, aumento da felicidadeíntima e ganho de energia, repercutindo positivamente na pré-intermissão, devido à autoridade moral(AU)

The objective of this article is the presentation of the author’s qualitative researchresults about leadership and assumption of consciential singularity, as a mean to collaboratein the development of leadership in a healthy and self-evolutionary way withinterested consciounesses. This article covers self challenges and benefits of leadershipdevelopment, as an assumption of consciential singularity. The research intereststarted with the identification of belief restraints observed on the authors themselvesand other leaders. The research method was the qualitative analysis of author’sexperiences and many cases observed in courses, voluntary guinea pigs, debates,counselings, and bibliography and filmography research as well. From the analysisone can assume that the assumption of personal leadership traits and singularity consciousnessare indispensable on the development of healthy leadership. The conquer ismeasurable by the evolutionary results, increase of internal happiness, and raise ofenergy level, resonantly positively in the preintermission, because of moral authority(AU)

El objetivo de este artículo es presentar resultados de la investigación cualitativade los autores sobre autoliderazgo e asunción de la singularidad conciencial, a fin decolaborar con las conciencias interesadas en el desenvolvimiento del liderazgo demodo sano e autoevolutivo. El artículo habla acerca de autodesafíos e beneficios en eldesenvolvimento del autoliderazgo, a partiendo de la asunción de la singularidad conciencial.El interés de la investigación surgió en la identificación de creencias limitadorasobservadas en los propios autores y en otros líderes. El método utilizado fue unanálisis cualitativo de las autovivencias de los autores y decenas de casos observadosen cursos, conscins-cobaias, debates, atendimientos, además de investigación bibliográficae filmográfica. Partiendo del análisis realizado, se concluye que la adopcióndel estilo propio de liderar y la asunción de la singularidad conciencial son elementosindispensables al desarrollo del autoliderazgo sano. La conquista es mensurable porlos resultados evolutivos, aumento de la felicidad íntima e ganancia de energía, repercutiendopositivamente en la pre-intermisión, debido a la autoridad moral(AU)