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There is widespread scientific evidence that validates tonic immobility (TI) as part of the trauma response in victims of rape, and criminal justice practitioners are increasingly trained in trauma-informed approaches. Yet, legal and policy definitions of consent do not fully recognize TI during the incident as evidence of nonconsent. Using a systematic review of U.S. law and policy regarding sexual violence and consent, this paper analyzes the substantial legal reform of rape law and definitions of consent, suggesting ways to further integrate TI into existing law and legal practices to improve public health approaches and justice responses for victims. [ABSTRACT FROM AUTHOR]

Death feigning is hypothesized to be an anti-predator behavior in which prey is temporarily immobilized in response to external stimuli. While death feigning may be an effective predator-defense strategy, there may be trade-offs in terms of energy and time for finding food and/or mating. The duration of death feigning is regulated by the balance of various selection pressures, and its duration is influenced by many internal and environmental factors. However, little is known about the factors that influence arousal from death-feigning behavior. Sex pheromones are important semiochemicals that affect reproductive success and may influence the duration of death-feigning behavior. In this study, we aimed to investigate the effects of sex pheromones on the death-feigning behavior of the sweet potato weevil (Cylas formicarius) by conducting laboratory experiments. The results showed that males had a significantly shorter death-feigning duration in the presence of sex pheromones because it aroused them from their death-feigning behavior, but females were unaffected. This is the first study to show that sex pheromones alter death-feigning behavior. The results of this study elucidate the factors influencing predator-avoidance behavior and reveal the impact of death-feigning behavior on prey reproduction under predation pressure. [ABSTRACT FROM AUTHOR]

The article focuses on the temporal dimension of migration, analyzing how time shapes the experiences of migrants both during their journeys and within reception systems. Topics include the impact of temporal uncertainty on migrants' lives, the role of time in creating different forms of immobility, and the exploitation of migrant time by capitalist systems within and beyond reception centers.

A study determined whether providing auditory enrichment to broiler chickens with or without regular human contact influenced stress response, underlying fearfulness, and growth performance. The experiment was conducted in a completely randomised design with a 3 × 2 factorial arrangement consisting of three auditory enrichment (AE) treatments and two human contact (HC) regimens. From days 1 to 35, a total of 480 day-old male broiler chicks were allotted to one of the three auditory enrichment treatments: no auditory enrichment (NE), auditory enrichment with classical music (Vivaldi's Four Season) (ME), or auditory enrichment with Quran recitation (Yaseen chapter) (QE). An equal number of chicks from each AE treatment were subjected to either no-human contact (NC) or regular human contact (the experimenter placed her right hand into the cage for 30 seconds twice daily) (RC). On day 7, the ME birds had significantly higher body weights (BW) than the control and QE birds. The BW of the QE chicks was significantly lower than that of their ME counterparts on day 14. HC had a negligible influence on the birds' BW, feed intake (FI), or feed conversion ratio (FCR). Neither AE nor HC significantly affected tonic immobility (TI) duration or number of induction attempts. ME and QE significantly affected serum levels of corticosterone (CORT) on days 14 and 21. However, HC did not affect CORT. In conclusion, ME has a beneficial effect on the performance of broilers during the early stage of growth. Exposure to ME or QE dampens stress response but not underlying fearfulness in chickens at market age. [ABSTRACT FROM AUTHOR]

We extend Conway's self-memory system by adding theory and data from shame, an emotion that disrupts the internalised ideals of society needed for a positive self-concept. The event that caused 273 undergraduates their greatest amount of shame was analyzed; 66% were not very negative except for producing shame. Ratings of post-event effects, including two measure of self (self-perceived weakness, and centrality to identity) and four clinical symptoms (intrusions, avoidance, anxiety, and depression), were attributed separately to the remembered event, behaviour during the event, and shame from the event. The effects of shame were generally as large as the those of the event and larger than those of the behaviour, demonstrating the importance of shame's effects. The Tonic Immobility Scale (TIS), which measures tonic immobility (i.e., freezing), was obtained for the event that produced the most tonic immobility but that was not the event that caused the most shame. The post-event symptoms measured on the event that caused the most shame and the TIS correlated highly, suggesting that shame and tonic immobility may belong to a cluster of phylogenetically conserved submissive defensive mechanisms that could account for effects currently attributed to goals in self-memory systems. [ABSTRACT FROM AUTHOR]

Death feigning is thought to have evolved primarily as a predator avoidance behavior, and has been reported in 10 of the 31 orders of insects. However, there have been no reports of death-feigning behavior in Mecoptera species. We found that larvae of two scorpionfly species, Panorpa japonica and P. pryeri, showed death feigning in response to external stimuli by brush poking stimulation. First, we examined the frequencies of death-feigning postures. The two species showed two different postures of death feigning, "straight" and "ball." Most of the 1st instar larvae of P. japonica and P. pryeri adopted the straight death-feigning posture. Next, we examined duration of death feigning. As the larval instar progressed, the death-feigning posture shifted from straight to ball in both Panorpa species. In P. japonica, the longest durations of death feigning were found in the 2nd to 3rd instars, while the longest duration of death feigning was found in the late 4th instar in P. pryeri larvae. [ABSTRACT FROM AUTHOR]

Tonic immobility (TI) is a state of temporary, involuntary motor inhibition that occurs in states of intense fear and has been studied among victims of sexual violence. Studies on TI are scarce and mainly focus on rape victims. The present study is a literature review of research that has examined TI in women victims of sexual violence. A database search was carried out using the Preferred data elements for systematic reviews and meta-analyses (PRISMA) method. In order to be included in the analysis, the manuscripts had to deal exclusively with research involving samples of subjects and the study analyzed TI in victims of sexual violence. In all, 11 manuscripts met the above criteria and were included in the review. Research describes that TI is characterized by two factors: fear and immobility. Quantitative research was conclusive in affirming the presence of a state of paralysis and fear in TI. The immobility factor is the determining factor in explaining the victim's lack of defense or resistance and causes effects such as trembling, physical and mental paralysis, inability to vocalize, and eye closure. In addition, TI has been correlated with long-term negative clinical manifestations as victims are more likely to suffer from post-traumatic stress disorder. These findings contribute to an understanding of TI in victims of sexual violence. Therefore, legal and care practitioners must be able to recognize TI to understand the victim's behavior, differentiate it from consent, and to be able to assist in their recovery. [ABSTRACT FROM AUTHOR]

Simple Summary: Light wavelength is very important for poultry physiology. In this study, five monochromatic lightings (white, green, yellow, blue, red) were applied to Japanese quails during the fattening period. The best results in terms of growth, viability, welfare, and developmental stability were found in quails treated with blue and green monochromatic lightings. The purpose of this study is to examine the impact of monochromatic illuminations at wavelengths of white (400–700 nm), green (560 nm), yellow (580 nm), blue (480 nm), and red (660 nm) on the performance and behavioral traits of Japanese quails throughout their fattening period. A total of 300 quails in five lighting experimental groups were housed in their conventional rearing cages. Weekly live weights of quails were measured individually, developmental stability was determined, and behavior and fear tests were performed. The body weight averages of quails exposed to blue, green, and yellow light were determined to be greater than those exposed to white and red light (p < 0.05). In terms of the mature weight parameter and the weight of the inflection point of the Gompertz growth model, the averages of the quails exposed to green and blue monochromatic lighting were higher (p < 0.05). The most negative findings on aggressive behavior were observed in birds exposed to monochromatic yellow and red light. Although the body weight of quails exposed to yellow monochromatic lighting was similar to that of quails exposed to green and blue monochromatic lighting, green and blue monochromatic lighting produced the best results in terms of growth, behavior, and developmental stability characteristics. Consequently, it is believed that consistently using green or blue monochromatic lighting programs when raising Japanese quails may provide economic advantages to the producers. [ABSTRACT FROM AUTHOR]

ABSTRACT: The fear response is a crucial adaptive mechanism for coping with environmental changes, and the individuals have different levels of fearfulness. The purpose of this study was to determine the status of the immune response and gut health in hens with different fear responses. A total of 80 healthy 75-wk-old native Lindian chickens were individually housed in conventional cages and categorized into high (TH) and low (TL) levels of fearfulness using the tonic immobility (TI) test. The immunological status and intestinal health of the laying hens were assessed, and the intestinal microbial community was sequenced using 16S rRNA testing. The results showed that the immune-related genes of interleukin (IL)-1β, IL-4, IL-6, and IgG were significantly upregulated in the spleen of TH hens compared with hens in the TL group (P < 0.01). The inflammatory immune-related genes Toll-like receptor (TLR)2, TLR4, nuclear factor (NF)-κB, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, IL-10, and IgG were significantly increased in the intestinal tract, whereas IL-4, IgA, and the intestinal barrier gene claudin-4 were significantly decreased in TH hens (P < 0.05). In addition, serum concentrations of IL-1β, IL-6, IL-10, interferon (IFN)-α and IgG were significantly higher in TH hens (P < 0.01). A high fear response also led to changes in gut microbial diversity, with a higher Simpson's index and lower β-diversity similarity than hens with a low-fear response (P < 0.05). The TH group showed an increase in 8 genera, including Bacillaceae and Coprococcus, whereas the genus Anaerorhabdus decreased (P < 0.05). The gut microbiota has also been associated with gut barrier genes, and inflammatory cytokines. Bartonella stimulates IL-1β and IgG secretion, whereas Lactobacillus inhibits IL-6 secretion, and Coprococcus and Subdoligranulum are associated with the maintenance of intestinal barrier function. The results of this study suggest that laying hens with high fear response levels have a more sensitive immune response and a more enriched gut microbiota, which may have positive effects on adapting to a complex environment.

Background: Victims of physical/sexual violence or sexual abuse commonly experience defense responses that result in feelings of guilt and shame. Although trauma-focused interventions are effective in treating post-traumatic stress disorder symptoms, the presence of trauma-related shame and guilt can potentially hinder the process of disclosure during treatment, thus diminishing their overall effectiveness. It is hypothesized that providing psychoeducation about common defense responses will reduce feelings of shame and guilt, thereby increasing receptivity to trauma-focused treatment. Objective: This paper describes the rationale, study design, and methods of the BLAME-LESS study. The effects of a brief online psychoeducation program will be compared with a waitinglist control group. The intervention aims to reduce feelings of trauma-related shame and guilt that adolescents experience regarding their own defense responses during and after physical/ sexual violence or sexual abuse. Methods: Adolescents (12 – 18 years old) with a history of physical/sexual violence or sexual abuse who suffer from trauma-related feelings of shame and guilt can participate in the study. The study follows a two-arm RCT that includes 34 participants. The primary outcomes includes trauma-related feelings of shame and guilt. The secondary outcomes includes PTSD symptoms, anxiety and depression symptoms, traumatic cognitions, readiness to disclose details of memories of the trauma, and motivation to engage in trauma-focused therapy. Assessments take place after screening, at baseline, two weeks after allocation to the intervention or waiting-list, and, only for the waiting-list participants, seven weeks after allocation to the intervention. Conclusions: There is a need for treatment approaches that target trauma-related feelings of shame and guilt. A recently developed brief online psychoeducation program on defense responses during and after trauma offers victims of physical/sexual violence or sexual abuse a free and accessible way to obtain reliable and valid information. The proposed RCT will evaluate the effectiveness of this online psychoeducation program. [ABSTRACT FROM AUTHOR]

In order to find standard transport time and its effect on the welfare, 480 marketable commercial broiler chickens (CARIBRO VISHAL; avg. 2.0 kg body weight) were transported for 2, 4, 8h and without transport in crates in three replicates in a completely randomized design. Transport affected welfare as well as behaviour of broiler chickens. Transport stretch impacted the gait score and tonic immobility with maximum aggravation with extended duration. Runaway results shown that 8h group exhibited more run-away time (279.20sec). Number of birds affected by physical injuries increases with the duration. Bodyweight change was significant among transported groups, especially 8h travelled group exhibited more (−8.21%) body weight loss. It is concluded that a transport period of more than 4h in Indian conditions is not recommended as its causing a significant level of stress in the birds leading to stress, production loss and hampering welfare of broilers.

The intriguing thanatosis was observed for the second time for a member of the family Chelodesmidae. This behavior was recorded for the species Pseudoleptodesmus rubescens (Gervais, 1836), in the municipality of Magé, state of Rio de Janeiro, Brazil.

Simple Summary: Perch access and age during access to perches may impact laying hen welfare. Our study aimed to determine the effects of early or late access to perches on behavioral measures of anxiety (AB: attention bias test) and fearfulness (TI: tonic immobility test) in laying hens. Pullets were housed in pens with or without access to perches until 17 weeks of age, at which point perch access either continued or was removed until 37 weeks of age, resulting in four treatments: continuous perch access (CP: 0–37 weeks), early perch access (EP: 0–17 weeks), late perch access (LP: 17–37 weeks), no perch access (NP). AB was performed at 21 and 37 weeks of age, and TI was performed at 20, 25, and 37 weeks of age. CP hens showed reduced anxiety and fearfulness, benefiting animal welfare, while NP hens showed increased anxiety and fearfulness. LP hens required around 16 weeks to adapt to the addition of perches in their environment, indicated by increased anxiety and fearfulness at 20 weeks of age that dissipated by week 37 of age. Removing perches in the EP pens resulted in increased fear and anxiety, which also disappeared by week 37 of age. Perch access benefits animal welfare, and removing or preventing access should be avoided. Perches can enhance laying hen welfare, but their effectiveness might be age-dependent. We investigated early and late perch access effects on anxiety and fear in pullets through attention bias (AB) and tonic immobility (TI) tests. Pullets (n = 728) were raised with or without multi-level perches: CP (continuous perch access: 0–37 weeks), EP (early perch access: 0–17 weeks), LP (late perch access: 17–37 weeks), and NP (no perch access). AB was conducted in weeks 21 and 37 (n = 84/week), and TI was performed in weeks 20, 25, and 37 (n = 112/week). CP hens fed quicker than EP, LP, and NP in AB at weeks 21 and 37 (p ≤ 0.05). CP and NP feeding latencies were stable, while EP and LP fed faster at week 37 (p ≤ 0.05). CP had the shortest TI at week 20 (p < 0.05). CP and LP had the shortest TI in weeks 25 and 37 (all p ≤ 0.05). Unlike NP, CP reduced anxiety and fear. Adding perches during laying (LP) raised anxiety at week 21, adapting by week 37, and removing pre-laying perches (EP) worsened fear at weeks 20 and 25 and anxiety at week 21, recovering by week 37. Adding or removing perches prior to the lay phase increased fear and anxiety, an effect that disappeared by week 37 of age. Our study indicates that continuous perch access benefits animal welfare compared to no perch access at all. [ABSTRACT FROM AUTHOR]

Our production animals typically suffer poor welfare, which can be revealed by measuring the affective state these animals are in. Negative affective state is linked to poorer welfare, and can be measured as fearfulness. While continuing to research how to improve animal welfare, a compliment to reduce negative affective state could therefore be to reduce individuals' fearfulness, similar to how negative affective states are medicated in humans. A proposed mechanism for this is via the monoaminergic systems. This is based on previous studies across species that have linked the serotonergic system and fear-related behaviour. We here aimed to experimentally manipulate the serotonergic system in red junglefowl hens (Gallus gallus), the main ancestor of all domesticated chickens. We measured fearfulness as latency remaining immobile in a tonic immobility test, and did so both before and after our experimental manipulation. We set out to experimentally manipulate the serotonergic system via sub-chronic dietary treatment of 5-hydroxytryptophan (the precursor to serotonin). Our dietary manipulation of 5-hydroxytryptophan significantly reduced measured fearfulness in the manipulated hens, while latency in tonic immobility did not significantly change in our unmanipulated, control hens. This finding is promising since it indicates that increased tryptophan levels can be used to reduce fearfulness. Additionally, our result suggests that this can be done noninvasively via food (instead of injections), thus presenting a potentially feasible manipulation also for larger settings. Nevertheless, the serotonergic system is complex and its role in modulating behaviour in the fowl should be explored further to evaluate our findings, and more directly explored also in a production setting. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this research is to adapt the "Tonic Immobility Scale (TIS)" which have been already developed in United States, to Turkish culture. Material and Method: Exploratory Factor Analysis and Confirmatory Factor Analysis (CFA) was performed for the validity of the scale and also the "Impact of Event Scale-Revised (IES-R)" and "Peritraumatic Dissociative Experiences Questionnaire (PDEQ" were used for criterion validity. Results: Cronbach Alpha value was used for the rehability method. As a result of the analysis of TIS, which has ten items and two sub-dimensions, x/Sd, RMSEA, IFI, CFL, SRMR, PGFI and PNFI compliance indexes were found to be at a good level. Cronbach's alpha value of TIS is a=0.90. Cronbach's alpha values of tonic immobility and fear subscales are a=0.87 and 0.80. Conclusion: It has been concluded that TIS is a suitable evaluation form in terms of validity and reliability and can be used to measure the freezing, immobility and unresponsiveness of individuals who have been exposed to trauma. [ABSTRACT FROM AUTHOR]

1. Comprehensive knowledge of innate fear in chickens has important implications for understanding the adaptation of native Japanese chickens in modern production and behavioural changes caused by modern breeding goals. Innate fear behaviour seen in chicks from six native Japanese chicken breeds;, Ingie (IG), Nagoya (NAG), Oh-Shamo (OSM), Tosa-Jidori (TJI), Tosa-Kukin (TKU) and Ukokkei (UK), were compared with those in two lines of White Leghorn (WL-G and WL-T) in tonic immobility (TI) and open field (OF) tests. 2. TI and OF tests were conducted for 267 chicks at 0-1 days of age in the eight breeds. Raw data for four TI traits and 13 OF traits were corrected for environmental factors. Breed differences were analysed by the Kruskal–Wallis test followed by the Steel Dwass post hoc test. Principal component (PC) analyses were conducted. 3. The results showed that OSM was the least sensitive to fear in both the TI and OF tests. The WL-G birds showed higher sensitivity to TI fear but lower sensitivity to OF fear. The PC analysis of OF traits classified the tested breeds into three groups: least (OSM and WL-G), moderate (IG, WL-T, NAG, TJI and TKU) and most sensitive (UK). [ABSTRACT FROM AUTHOR]

ABSTRACT The COVID-19 pandemic has imposed a health crisis around the world. Health professionals are frequently exposed to stressors that put them at high risk for the development or progression of disabling mental disorders, including posttraumatic stress disorder (PTSD). To understand how pandemic stressors have affected the mental health of healthcare workers, our group conducted a longitudinal and nationwide survey. We investigated the occurrence of traumatic events related to the COVID-19 pandemic and the association between exposure to these events and PTSD symptomatology. Importantly, we also investigated factors that might increase or decrease the risk for PTSD. Depression symptoms were also investigated. The results of the first wave of the project were published in a series of three articles, each focused on different risk or protective factors. The results showed that female sex, young age, a lack of adequate personal protective equipment, social isolation and a previous history of mental illness were consistent predictors of PTSD symptoms. Healthcare workers who reported high levels of peritraumatic tonic immobility, a defensive response that is involuntary, reflexive, and evoked by an intense and inescapable threat, also exhibited an increase in the probability of being diagnosed with PTSD. On the other hand, professional recognition had a negative relationship with PTSD and depression symptoms, emerging as a significant protective factor for psychological health. The identification of protective and risk factors in these situations is crucial to guide the adoption of long-term measures in work environments that will enhance the psychological health of these professionals.

The purpose of this study is to examine the impact of monochromatic illuminations at wavelengths of white (400–700 nm), green (560 nm), yellow (580 nm), blue (480 nm), and red (660 nm) on the performance and behavioral traits of Japanese quails throughout their fattening period. A total of 300 quails in five lighting experimental groups were housed in their conventional rearing cages. Weekly live weights of quails were measured individually, developmental stability was determined, and behavior and fear tests were performed. The body weight averages of quails exposed to blue, green, and yellow light were determined to be greater than those exposed to white and red light (p < 0.05). In terms of the mature weight parameter and the weight of the inflection point of the Gompertz growth model, the averages of the quails exposed to green and blue monochromatic lighting were higher (p < 0.05). The most negative findings on aggressive behavior were observed in birds exposed to monochromatic yellow and red light. Although the body weight of quails exposed to yellow monochromatic lighting was similar to that of quails exposed to green and blue monochromatic lighting, green and blue monochromatic lighting produced the best results in terms of growth, behavior, and developmental stability characteristics. Consequently, it is believed that consistently using green or blue monochromatic lighting programs when raising Japanese quails may provide economic advantages to the producers.

Males’ and females’ reproductive strategies may differ, potentially leading to sexual conflict. Increased efforts by males (harassment, forced copulation, intimidation) to gain access to females could even negatively affect female survival and thus lead to reproductive failure for both individuals. In anurans, a higher mortality risk of mating females has been reported in explosive breeding species. During these mating events, several males cling to a female, which are mostly unable to get rid of the unwanted males. This can lead to the female's death. From the literature, it seems that females of explosive breeding frogs have no means to reject unwanted males. Here we describe female mate avoidance behaviours in the European common frog. We observed three female avoidance behaviours, namely ‘rotation’, ‘release call(s)’ and tonic immobility (death feigning). These behaviours were significantly associated with smaller female body size, and smaller females were more successful in escaping amplexus. Tonic immobility as a tactic to avoid mating or male harassment has only been observed in a handful of species and only in one other amphibian. Our observations show that females in explosive breeding frogs may not be as passive and helpless as previously thought.

Our production animals typically suffer poor welfare, which can be revealed by measuring the affective state these animals are in. Negative affective state is linked to poorer welfare, and can be measured as fearfulness. While continuing to research how to improve animal welfare, a compliment to reduce negative affective state could therefore be to reduce individuals’ fearfulness, similar to how negative affective states are medicated in humans. A proposed mechanism for this is via the monoaminergic systems. This is based on previous studies across species that have linked the serotonergic system and fear-related behaviour. We here aimed to experimentally manipulate the serotonergic system in red junglefowl hens (Gallus gallus), the main ancestor of all domesticated chickens. We measured fearfulness as latency remaining immobile in a tonic immobility test, and did so both before and after our experimental manipulation. We set out to experimentally manipulate the serotonergic system via sub-chronic dietary treatment of 5-hydroxytryptophan (the precursor to serotonin). Our dietary manipulation of 5-hydroxytryptophan significantly reduced measured fearfulness in the manipulated hens, while latency in tonic immobility did not significantly change in our unmanipulated, control hens. This finding is promising since it indicates that increased tryptophan levels can be used to reduce fearfulness. Additionally, our result suggests that this can be done non-invasively via food (instead of injections), thus presenting a potentially feasible manipulation also for larger settings. Nevertheless, the serotonergic system is complex and its role in modulating behaviour in the fowl should be explored further to evaluate our findings, and more directly explored also in a production setting.

Tonic immobility is a passive antipredator strategy employed late in the predation sequence that may decrease individual mortality in prey animals. Here, we investigate how energetic state and genetic predisposition influence antipredator decision-making in green lacewing larvae, Chrysoperla plorabunda (Fitch), using simulated predatory encounters. We demonstrate that tonic immobility is a plastic response influenced by energetic resource limitation. Larvae exposed to 1 or 2 days of food deprivation initiate tonic immobility more often and with less physical provocation than individuals fed ad libitum. Recently molted individuals exposed to food deprivation, the individuals most energetically challenged, engage in tonic immobility at a higher rate than any other group. We also find that variation in antipredator strategy between individuals is partly the result of within-population genetic variation. We estimate the propensity to enter tonic immobility to have a broad-sense heritability of 0.502. Taken together our results suggest that larval lacewings under energetic stress are more likely to engage in tonic immobility. Yet, energetic state does not explain all within-population variation, as individuals can have a genetic predisposition for tonic immobility. [ABSTRACT FROM AUTHOR]

This study investigated the effect of various pasture species on the welfare and behavior of slow-growing broiler chickens in the free-range production system. After 21 days completely indoors, the birds were permitted access to outdoor pens cultivated with one of the following pasture treatments: Medicago sativa (A), Trifolium repens (WC), Lolium perenne (PR), and a mixture (Mix, A + WC + PR). The range availability was restricted between 08:30 and 16:30 daily. It was found that pasture type had a significant effect on the fluctuating asymmetry of the face and radius length (P < 0.01). Duration of tonic immobility and blood parameters did not differ among the pasture species and between sexes at 11 weeks of broiler age (P > 0.05). Pasture treatment had no significant effect on broiler behaviors (P > 0.05). However, the age of broilers had a significant effect on pecking, dustbathing, and scratching (P < 0.01). Pecking behavior was affected by the time of the day; morning and afternoon (P < 0.01). Location had a significant effect on pecking and stretching behaviors (P < 0.01). In the study, dustbathing behavior was significantly affected by the interaction between location and age (P < 0.01), age and time of the day (P < 0.01), and location, age, and time of the day (P < 0.05). Scratching behavior was significantly affected by the interaction between location and time of the day (P < 0.05) and location, age and time of the day (P < 0.01). Stretching behavior was significantly affected by the interaction between location and age (P < 0.05) and location, age and time of the day (P < 0.05). It was concluded that access to the studied pasture species does not affect the evaluated welfare traits and observed behaviors. Therefore, it is suggested that other pasture species should be investigated to identify their effect on slow-growing strains in the free-range production system. [ABSTRACT FROM AUTHOR]

Tonic immobility (TI) is a phylogenetically conserved, passive, obligatory defense mechanism commonly engaged during sexual and physical assaults. During TI, people become immobile while remaining conscious and later reexperience intrusive memories of both their assault and of its accompanying immobility. Here we show that this well-studied biological process has powerful effects on memory and other processes. Participants had experienced either a serious sexual (n = 234) or physical (n = 137) assault. For both the assault and its accompanying immobility, the standard measure of the peritraumatic severity of TI correlated between.40 and.65 with post-assault effects on memory, including memory of the assault and memory of the immobility, the two memory-based self-concept measures of self-blame and event centrality, and post-assault anxiety and depression. The correlations with TI were much higher than other peritraumatic characteristics commonly used to predict and describe posttraumatic effects in assaults and other traumas. The results suggest that TI should be considered for a broader, more biologically based and ecologically valid understanding of the effects of trauma on memory and memory-based reactions. [ABSTRACT FROM AUTHOR]

Laws act as levers to influence human behavior. Their effectiveness hinges on understanding an accurate model of human nature, particularly the psychological and behavioral components of that nature. Evolved sex differences in our sexual psychology are sometimes moderate to large in magnitude and highly replicable. Women, for example, typically judge the same set of actions—such as leering, sexual jokes, or unwelcome workplace advances—as more sexually harassing and upsetting than do men. When a generic "reasonable person" standard is applied to adjudicating sexual harassment cases, this standard can harm women if judges and juries are populated by "reasonable men." Other relevant sex differences involve fears evoked by stalking victimization, defenses against rape such as tonic immobility, and negative emotions in response to certain forms of unsolicited sexual imagery. This paper argues that existing psychological sex differences should inform the construction and implementation of policies and laws that regulate forms of sexual violence such as sexual harassment, mate stalking, and rape. [ABSTRACT FROM AUTHOR]

Background. One priority for animal welfare is for animals to experience less fear, especially during human contact. For domestic animals, breeds that are less fearful may provide genetic resources to develop strains with improved welfare due to lower susceptibility to fear. Genetic predispositions inherited in these breeds might reflect the large diversity of chicken breeds. The goal of the present study was to systematically test a diverse group of chicken breeds to search for breeds that experience less fear. Methods. Nineteen chicken breeds from commercial hybrid lines, native layer-type, meat-type and dual-purpose breeds, ornamental breeds as well as bantam breeds were tested in a standardized tonic immobility (TI) test. Chickens were manually restrained on their back, and the time to first head movement and first leg movement, the duration of TI, as well as the number of attempts needed to induce TI were measured. Results. The TI response differed among chicken breeds (p≤0:001) for naïve, mature hens. The median number of attempts required to induce TI ranged from 1 to 2 and did not differ significantly among breeds. Median durations were much more variable, with Lohmann Brown showing shortest durations (6 s, 12 s, 58 s for time to first head movement, first leg movement and total duration of TI, respectively). In contrast, medians reached the maximum of 600 s for all three measures in German Creepers. Repeated tests on the same individuals did not affect attempts needed to induce TI nor TI durations. Breeds clustered into two main groups, with layer-type native breeds and ornamental breeds having longer TI durations, and bantam, dual-purpose and meat-type native breeds having shorter TI durations. Conclusions. Our findings provide evidence for substantial variation of fearfulness among breeds. This variation could be linked to the intended use during the breed's specific history. Knowledge and quantitative measurement of these behavioural responses provide the opportunity to improve welfare through selection and future breeding. [ABSTRACT FROM AUTHOR]

Differences between daytime and night-time behaviors are common in insects due to potential trade-offs between predator avoidance and foraging. While diel effects on average behavior are well documented, it remains unclear whether individuals differ in how they adjust their behavior between daytime and night-time. In this study, we focused on two light dependent behaviors, activity and tonic immobility, in the water scorpion (Nepa hoffmanni). Each individual was assayed for each behavior six times during the day and six times at night. Then, we explored diel differences in (1) average behavior, (2) among-individual variation in behavior, (3) individual rank order of behavioral expression, and (4) the sign and magnitude of behavioral syndromes (among-individual correlations between behaviors). At night, N. hoffmanni was more active and exhibited shorter periods of tonic immobility. Among-individual variation in activity was greater at night than during the day, but among-individual variation in tonic immobility did not differ between day and night. Individuals also differed in their diel plasticity in activity but not in tonic immobility. Thus, both (1) day–night differences in among-individual variation and (2) individual variation in diel plasticity contributed to the light-dependent sign of the behavioral syndromes. Our findings highlight the need for individual-level studies to fully elucidate diel influences on animal behavior. We suggest that day–night differences in behavioral syndromes as well as in selection might be key to behavioral evolution, especially in animals active during both day and night. [ABSTRACT FROM AUTHOR]

Effects of lighting program during production period on organs weight, immune responses, gait scoring, and tonic immobility reaction were evaluated using 900 male day-old broiler chicks (ROSS 308) in three houses. In each house, chicks were randomly allocated to 30 pens of 10 birds each. From day 7 upto 3 days to the end of the production period, three lighting programs including 17L:7D for house 1, 14L:10D for house2, and 12L:12D for house 3 were used. For immune system evaluation SRBC injection and CBH test were used. Blood samples for CBC were collected on day 40. Gait scoring and tonic immobility test were done on day 41. On day 42, 30 birds from each house (one per pen) were selected randomly, euthanized, and carcass and organ weights were recorded. Using 12 hours of darkness, comparing with 7 or 10 hours, decreased gastrointestinal weight while increased testis weight (P<0.05). Increasing the darkness period, increased the eye weight linearly. Incorporation of 10 or 12 hours of darkness decreased PCV percent (P<0.001). Immune system responses were improved by 10 hours of darkness (P<0.05). Application of 10 hours of darkness also improved the gait scoring and tonic immobility values comparing to 2 other darkness periods (P<0.05). Overall, according to the results of this study, using 10 hours of darkness would be beneficial and advisable in broiler production. [ABSTRACT FROM AUTHOR]

ABSTRACT: High fearfulness in commercial laying hens can negatively affect production parameters and animal welfare. Brown and white egg layers differ in several behavioral characteristics, though reported differences in fearfulness are inconsistent. A meta-analysis was conducted to determine whether there are systematic differences in measures of fearfulness between brown and white layers. Twenty-three studies that examined either 1 or both of 2 behavioral tests were included: tonic immobility (TI) (longer duration = higher fearfulness, 16 studies) and novel object (NO) test (lower approach rate = higher fearfulness, 11 studies). The 2 tests were analyzed separately. TI analyses: A generalized linear mixed effect model (GLMM) with a lognormal distribution was fitted to describe the data with experiment nested in study as a random effect. Explanatory (X) variables were considered through backward selection, where potential X-variables included color (brown vs. white layers), decade (1980s, 2000s, 2020s), age (prelay vs. in lay), genetic stock (hybrid vs. grand-/parent stock), and methodology (back vs. side position). NO test analyses: univariable GLMMs with a beta distribution were fitted with approach rate as the Y-variable and color, decade, age, stock, or 2 methodological factors (test duration, single vs. group testing) as X-variables. Models were evaluated by assessing information criteria, residuals/random effect normality, significance of X-variables and model evaluation statistics (mean square prediction error, concordance correlation coefficient). TI duration was best explained by a color-by-decade interaction (P = 0.0006). Whites in the 1980s had longer TI durations (709.43 ± 143.88 s) than browns in the 1980s (282.90 ± 59.70 s), as well as in comparison to browns (208.80 ± 50.82 s) or whites (204.85 ± 49.60 s) in the 2020s. The NO approach rate was best explained by color (P ≤ 0.05 in 3 models), age (P < 0.05 in 3 models), and decade (P = 0.04). Whites had a higher approach rate (0.7 ± 0.07) than browns (0.5 ± 0.11), birds in lay a higher rate (0.8 ± 0.07) than birds prelay (0.4 ± 0.12), and approach rate for papers published in the 2000s (0.8 ± 0.09) was higher than in the 2020s (0.2 ± 0.12). The phylogenetic difference in the 1980s was no longer detectable after enforcing an upper limit on TI durations (10 min), as became common practice in later studies. Our findings suggest that phylogenetic differences in fearfulness and changes over time are test dependent, and this raises important questions and potential consequences for assessing hen welfare in commercial egg production.

Background One priority for animal welfare is for animals to experience less fear, especially during human contact. For domestic animals, breeds that are less fearful may provide genetic resources to develop strains with improved welfare due to lower susceptibility to fear. Genetic predispositions inherited in these breeds might reflect the large diversity of chicken breeds. The goal of the present study was to systematically test a diverse group of chicken breeds to search for breeds that experience less fear. Methods Nineteen chicken breeds from commercial hybrid lines, native layer-type, meat-type and dual-purpose breeds, ornamental breeds as well as bantam breeds were tested in a standardized tonic immobility (TI) test. Chickens were manually restrained on their back, and the time to first head movement and first leg movement, the duration of TI, as well as the number of attempts needed to induce TI were measured. Results The TI response differed among chicken breeds (p ≤ 0.001) for naïve, mature hens. The median number of attempts required to induce TI ranged from 1 to 2 and did not differ significantly among breeds. Median durations were much more variable, with Lohmann Brown showing shortest durations (6 s, 12 s, 58 s for time to first head movement, first leg movement and total duration of TI, respectively). In contrast, medians reached the maximum of 600 s for all three measures in German Creepers. Repeated tests on the same individuals did not affect attempts needed to induce TI nor TI durations. Breeds clustered into two main groups, with layer-type native breeds and ornamental breeds having longer TI durations, and bantam, dual-purpose and meat-type native breeds having shorter TI durations. Conclusions Our findings provide evidence for substantial variation of fearfulness among breeds. This variation could be linked to the intended use during the breed’s specific history. Knowledge and quantitative measurement of these behavioural responses provide the opportunity to improve welfare through selection and future breeding.

Caiman latirostris is a Neotropical crocodilian for which there is scarce natural history information in regard to other species, as also about survey methods used by field researchers. In this work we report the capture methodology implemented during population monitoring in northern Uruguay and some observations about defensive and feeding behaviours. We found the use of a metallic clamp as very useful for capturing juveniles and subadult individuals (< 120 cm total length) in vegetated habitats, while a wire snare was used for adults. Regardless locomotor escape, we provide a reappraisal of defensive behaviours in the presence of humans, with particular comments on tonic immobility. In addition, we suggest an apparent case of carcass consumption (scavenging) for the species, a presumedly common behaviour but sometimes hard to observe in wild crocodilians.

Simple Summary: Tonic immobility (TI) is an essential anti-predator behavior to reduce the effect of predators. To know the relationship between mating behavior and TI, the effect of TI on courtship and copulation, as well as the effect of courtship and copulation on TI, were investigated in the sweetpotato weevil (SPW), Cylas formicarius. In the present study, we found the duration of TI was significantly reduced in the stage of courtship and copulation. The pairs with males from the L-strain (SPW with longer period of TI) showed lower frequency and longer duration of courtship than pairs with males from the S-strain (SPW with shorter duration of TI). Similarly, males from L-strain pairs showed a longer period of copulation than pairs with males from the S-strain. However, there is no significant difference in the frequency of copulation and the success of insemination. The results of our study clearly demonstrate that SPW mating behavior and TI are negatively correlated. Numerous studies have confirmed that the trade-off between anti-predator behavior and mating behavior occurs in certain insect species. This suggests that insects invest more in anti-predator behavior, and fewer resources or time can be used in mating behavior. However, few studies focus on tonic immobility, an important anti-predator behavior in nature, and different stages in mating behavior. Tonic immobility (TI) is considered to be an important anti-predator behavior. Herein, we investigated the relationship between TI and mating behavior in the sweetpotato weevil (SPW), Cylas formicarius. As the first step, we artificially selected SPWs for the longer duration of TI (L-strain) and the shorter duration of TI (S-strain). The effect of courtship and copulation on the duration of TI in two artificial selection strains was tested. Furthermore, we compared the frequency and duration of two mating behaviors in four kinds of pairs (LF×LM, LF×SM, SF×LM, and SF×SM: LM—L-strain male; SM—S-strain male; LF—L-strain female; SF—S-strain female). Finally, we tested insemination success in four kinds of pairs (male and female SPWs from the L-strain or the S-strain). The courtship and copulation significantly reduced the duration of TI. Pairs with males from the L-strain showed lower frequency and longer duration of courtship than pairs with males from the S-strain. Similarly, males from L-strain pairs showed a longer period of copulation than pairs with males from the S-strain. However, there is no significant difference in the frequency of copulation and the success of insemination. These results support that there was a significant trade-off between TI and courtship as well as copulation in the SPW. [ABSTRACT FROM AUTHOR]

Transportation before slaughtering causes bad effects on chicken welfare and health, but little is known about the effect of probiotic dietary fed in broiler chickens having transport stress. So, this study was designed to detect the effects of two doses of a probiotic (Bacillus subtilis) on some stress indicators, antioxidant activity and fear response of broiler chickens exposed to transportation stress. Two hundred and ten broiler chicks were distributed among 21 floor pens (10 chicks in each pen), each pen was exposed to one of three diet treatments containing a probiotic at 0 (control), 0.25 (0.25X), and 0.5 (0.5X) g/kg. At 35 days old, birds were exposed to transportation and then blood samples were collected for measuring stress and antioxidant markers. The serum corticosterone and cholesterol levels were decreased in probiotic fed birds in comparison with controls (P < 0.05). Compared to control broiler chickens, 0.5X birds had higher levels of catalase and serum superoxide dismutase (P < 0.05). In addition, the 0.5X birds spent less time in the tonic immobility test (P = 0.0427). The results suggest that the probiotic supplement may prove to be an important management tool for the broiler industry to diminish the negative effects of transport stress, potentially safeguarding the welfare and health of broiler chickens. [ABSTRACT FROM AUTHOR]

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There exists growing evidence that animal personality (consistent between individual differences in behavior) can influence an individual's fitness. Furthermore, limitations in behavioral plasticity may cause personality-mediated tradeoffs to occur, for example, between speed and accuracy in decision making. We explored whether various measures of personality could predict speed-accuracy tradeoffs in mate selection using Pharaoh cicadas (Magicicada septendecim) and examined the phenotypic traits predicting male mating performance and advertisement rates. We assessed whether male exploration behavior, boldness, and weight could predict a male's overall copulation attempt rate (the number of attempted copulations with conspecifics of either sex), the number of errors a male made when selecting a mate (the number of same-sex copulation attempts), and male reproductive performance (whether a male successfully copulated with a female). We also assessed whether personality-dependent variation in male advertisement rate (the number of calling song bouts) might underpin the correlation between exploration behavior and mating performance. Although male exploration behavior did not predict male advertisement rate, we found that faster-exploring males exhibited higher overall rates of attempted copulations while also attempting more same-sex copulations, compared to slower-exploring males, suggesting a personality-mediated speed-accuracy tradeoff. Despite making more mate choice errors, however, faster explorers were more likely to successfully copulate with females, compared to slower explorers, indicating that speed may be favored over accuracy in systems where heavily male-biased sex ratios lead to scramble competition. Overall, this work highlights the role of personality in sexual selection and demonstrates that personality can influence speed-accuracy trade-offs in mating. [ABSTRACT FROM AUTHOR]

Even though personality is a major determinant of individual survival, the development of animal personality traits is still poorly understood. Beyond an individual's genetic background, personality may be shaped by the conditions experienced during embryonic development. Light is a salient and variable ecological factor that can affect organismal physiology, establish brain asymmetries and ultimately modulate postnatal phenotypes across multiple taxa. Exposure to light is known to vary among avian embryos due to changes in parental incubatory constancy, but whether differences in the prenatal light environment can influence offspring personality development has rarely been explored. Here, we investigated whether the prenatal light environment shapes a key dimension of animal personality, the shy–bold axis, in hatchlings of a semiprecocial seabird, the yellow-legged gull, Larus michahellis. In gulls, the prenatal light environment may be especially important for last-laid eggs, as parental attendance during late incubation is more variable for last-laid than for senior eggs. We manipulated the levels of embryonic exposure to light (within the natural range previously documented in the wild) during the last stages of egg incubation and assessed differences in boldness in newly hatched junior chicks. We then used structural equation modelling to explore whether the effect of prenatal light exposure on the shy–bold axis is linked to the establishment of brain asymmetries (lateralization) and/or changes in plasma corticosterone levels. Prenatal light exposure promoted bolder phenotypes in gull chicks, which may improve their individual performance when competing for parental resources. Prenatal light also promoted the lateralization of the begging behaviour in newly hatched chicks, which was negatively associated with boldness. Finally, light induced changes in glucocorticoid levels, but these changes did not impact chicks' personality. Our findings unambiguously confirm that the prenatal light environment strongly affects the development of shy–bold phenotypes in gull hatchlings through a complex multipath mechanism. • Can the prenatal environment shape animal personality? • Last-hatched gull eggs are highly exposed to sunlight during late incubation. • We explored whether prenatal exposure to light shapes boldness in hatchlings. • Prenatal light promoted bold phenotypes and brain lateralization in gull chicks. • These adjustments might improve chick performance under competitive disadvantage. [ABSTRACT FROM AUTHOR]

Perches can enhance laying hen welfare, but their effectiveness might be age-dependent. We investigated early and late perch access effects on anxiety and fear in pullets through attention bias (AB) and tonic immobility (TI) tests. Pullets (n = 728) were raised with or without multi-level perches: CP (continuous perch access: 0–37 weeks), EP (early perch access: 0–17 weeks), LP (late perch access: 17–37 weeks), and NP (no perch access). AB was conducted in weeks 21 and 37 (n = 84/week), and TI was performed in weeks 20, 25, and 37 (n = 112/week). CP hens fed quicker than EP, LP, and NP in AB at weeks 21 and 37 (p ≤ 0.05). CP and NP feeding latencies were stable, while EP and LP fed faster at week 37 (p ≤ 0.05). CP had the shortest TI at week 20 (p < 0.05). CP and LP had the shortest TI in weeks 25 and 37 (all p ≤ 0.05). Unlike NP, CP reduced anxiety and fear. Adding perches during laying (LP) raised anxiety at week 21, adapting by week 37, and removing pre-laying perches (EP) worsened fear at weeks 20 and 25 and anxiety at week 21, recovering by week 37. Adding or removing perches prior to the lay phase increased fear and anxiety, an effect that disappeared by week 37 of age. Our study indicates that continuous perch access benefits animal welfare compared to no perch access at all.

This study aims to determine the effects of blue and green monochromatic, blue-green combination, and blue-green mixed led lighting systems on growth, fear, and carcass characteristics of broilers reared in an extensive indoor system. Experimental groups were formed as follows; 1-conventional (incandescent), 2-blue, 3-green, 4-blue-green combined (blue for the first 10 days, then green), 5-green–blue combined (green for the first 10 days, then blue), and 6-blue-green intermittent (alternating every 5 min) monochromatic lightings. It was detected that the average values of the body weight of chickens at 42 and 56 days of age in the green–blue group were higher than those of the other treatment groups (both P < 0.05). It was determined that the broilers in the green and green–blue groups had higher means of the β0 parameter of Gompertz model. The tonic immobility, emergence test, home cage avoidance test, a looming human test, and box plus experimenter test were applied to determine the fear responses. It was determined that the worst results for fear responses of broilers were in the intermittent lighting group and green–blue combined group. As a result, it was determined that the application of green monochromatic lighting in the first 10 days of the fattening period and blue monochromatic lighting in the following period positively affected growth and slaughter-carcass characteristics. However, it was found that broilers reared under green–blue combined lighting had high fear levels. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effects of different sound stimulant applied to embryos during the incubation on performance characteristics, fear responses, and developmental stability of Japanese quails. For this purpose, a quiet environment, species-specific relaxing sounds, and species-specific disturbing sounds were applied to quail eggs placed in three homologous incubators in different rooms. A constant sound pressure (65 decibels) was used throughout the incubation, with stimulation for two minutes out of every twenty minutes. There were no differences between the experimental groups in terms of hatch weight and weekly body weights. Similarly, sound stimulation had no positive or negative effects on parameters of the Gompertz growth curve and slaughter-carcass traits. The mean values of tonic immobility duration of quails in both the disturbance and comfort group (72.15 and 71.35 sec, respectively) were higher than that of the control group (51.14 sec, P < 0.05). Moreover, when the developmental stability of the bilateral features was examined, fewer fluctuating asymmetry cases were detected in the disturbance and comfort groups. As a result, it is possible to say that the sound models applied to the embryos during incubation did not affect the performance characteristics, but had negative effects on developmental stability and fear responses. [ABSTRACT FROM AUTHOR]

Many animal species 'play dead' or feign death (in some cases called tonic immobility) as a defence strategy against predators, including some ants, although triggers and durations are poorly understood. We repeatedly observed such death-feigning behaviour in Polyrhachis femorata ants that occupied pygmy-possum nest boxes deployed on Kangaroo Island following the 2019–2020 bushfires that burnt half of the island. Most of the 759 bat and pygmy-possum boxes (901 cavities) were on burnt ground. In 3312 box cavity checks on 13 diverse properties during monitoring visits, 28 of 40 P. femorata records (first for South Australia) occurred in unburnt Critically Endangered Narrow-Leaf Mallee Woodland community, seven in adjacent mallee community containing narrow-leaf mallee, three in cup gum unburnt habitat, and two in one box on burnt ground. Fire may have affected the abundance and re-establishment of the species. Polyrhachis femorata engages in a surprising defensive immobility strategy in boxes, since it is not only undertaken by individuals facing a potential predator, but also by entire colonies. The death-feigning behaviours were complemented by plugging box entrances. Nest boxes may be used to study this mysterious behaviour in this poorly known species, although frequent observation could lead to nest abandonment by the ant. The ant Polyrhachis femorata , a first record for South Australia, feigned death individually and in colonies in wooden nest boxes made for pygmy-possums. The ant was most common in unburnt Critically Endangered Narrow-Leaf Mallee Woodland community on Kangaroo Island. Death feigning is likely to deter potential predators and could be studied with nest boxes placed on trees. Photograph by Sophie Petit. [ABSTRACT FROM AUTHOR]

Death feigning, a state of immobility observed in many animals in response to external stimuli, is an anti-predator behaviour. Although previous studies showed that death-feigning behaviours are quantitative genetic traits, the knowledge of the heritable basis of death-feigning behaviour is lacking. To investigate the heritable basis of death-feigning behaviour, we used 3 laboratory strains of a braconid parasitoid wasp, Heterospilus prosopidis. The heritable basis using half-sib analysis, and the effects of different geographical backgrounds, rearing conditions in the laboratory, and host age were evaluated. The results of the half-sib analysis showed that the frequency of death feigning varied among sires, suggesting a certain extent of additive genetic variance. Also, the frequency of death feigning varied between geographical backgrounds and among strains. Death-feigning frequency was not affected by the age of the host. Our findings highlight the importance of genetic factors underlying the basis of the death-feigning behaviour and provide support for the genetic alterations of traits from the perspective of evolution in various animal species., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Evolutionary Biology.)

The survival of captive-reared pheasants in the wild depends primarily on their ability to avoid predators, therefore, pheasants need to maintain their innate anti-predatory behaviour. The aim of this study was to assess the effects of age and disturbance on tonic immobility (TI) in pheasants (Phasianus colchicus) kept in a commercial rearing facility. TI tests were performed in pheasants aged 8, 10, 12, 14 and 16 weeks. Randomly selected pheasants of the same age were tested either immediately after capture (group C) or after exposure to various stimuli/disturbance (group D). No significant differences in the number of attempts to induce TI were found between the observed groups of pheasants (the vast majority of pheasants remained immobile on the first attempt). The effect of age was found only in group D, where birds aged 14 and 16 weeks showed a reduction in the duration of TI compared to younger birds. In group C, the duration of TI in pheasants of different ages did not differ. The results document a change in the duration of TI in response to an intense stimulus depending on the age of captive-reared pheasants. Knowledge of changes in anti-predatory behaviour depending on age and habituation to the environment and new stimuli is essential when determining the optimal age for pheasants to be released into the wild considering its impact on the subsequent survival of the released birds. Birds released at an older age and thus accustomed to repeated disturbances during captive rearing may have impaired defence behaviour. [ABSTRACT FROM AUTHOR]