PaperPlayer biorxiv animal behavior and cognition

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.21.354019v1?rss=1 Authors: Reece, J., Couvillon, M. J., Grueter, C., Ratnieks, F., Reyes-Aldasoro, C. C. Abstract: This work describe an algorithm for the automatic analysis of the waggle dance of honeybees. The algorithm analyses a video of a beehive with 13,624 frames, acquired at 25 frames/second. The algorithm employs the following traditional image processing steps: conversion to grayscale, low pass filtering, background subtraction, thresholding, tracking and clustering to detect run of bees that perform waggle dances. The algorithm detected 44,530 waggle events, i.e. one bee waggling in one time frame, which were then clustered into 511 waggle runs. Most of these were concentrated in one section of the hive. The accuracy of the tracking was 90% and a series of metrics like intra-dance variation in angle and duration were found to be consistent with literature. Whilst this algorithm was tested on a single video, the ideas and steps, which are simple as compared with Machine and Deep Learning techniques, should be attractive for researchers in this field who are not specialists in more complex techniques. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.20.390245v1?rss=1 Authors: Monari, P. K., Rieger, N. S., Hartfield, K., Schefelker, J., Marler, C. A. Abstract: Social context is critical in shaping behavioral responses to stimuli and can alter an individual's behavioral type, which would otherwise be fixed in social isolation. For monogamous biparental vertebrates, social context is critical as interactions are frequent and consistent, involving high interindividual dependence and cooperation that can lead to large fitness impacts. We demonstrate that in the strictly monogamous and highly territorial California mouse, individuals alter approach response to an aggressive conspecific playback stimulus, barks, to become more similar to their partner during early bonding prior to pup birth; an effect distinct from assortative mating. Additionally, sustained vocalizations, an affiliative ultrasonic vocalization when used between members of a pair, are associated with increased behavioral convergence following pair formation suggesting a vocal communication role in emergent pair behavior. We identified the neuropeptide oxytocin as sufficient to promote behavioral convergence in paired individuals who differed in their initial behavioral type, as characterized by approach behavior. Social context, specifically pair-bonding, appears vital for behavioral responses to aggressive signals. While non-bonded animals maintained stable responses, pair-bonding led to a pair emergent property, a convergence in behavioral responses. This convergence can be driven by oxytocin, revealing a significant expansion in oxytocin's effects on behavioral coordination. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.18.388702v1?rss=1 Authors: Heslin, K. A., Brown, M. F. Abstract: Helping behavior tasks are proposed to assess prosocial or empathic behavior in rodents. This paradigm characterizes the behavior of subject animals presented with the opportunity to release a conspecific from a distressing situation. Previous studies found a preference in rats for releasing restrained or distressed conspecifics over other controls (e.g., empty restrainers or inanimate objects). An empathy account was offered to explain the observed behaviors, claiming subjects were motivated to reduce the distress of others based on a rodent homologue of empathy. An opposing account attributes all previous results to subjects seeking social-contact. To dissociate these two accounts for helping behavior, we presented subject rats with three simultaneous choice alternatives: releasing a restrained conspecific, engaging a non-restrained conspecific, or not socializing. Subjects showed an initial preference for socializing with the non-restrained conspecific, and no preference for helping. This result contradicts the empathy account, but is consistent with the social-contact account of helping behavior. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.19.389999v1?rss=1 Authors: Saddler, M. R., Gonzalez, R., McDermott, J. H. Abstract: Computations on receptor responses enable behavior in the environment. Behavior is plausibly shaped by both the sensory receptors and the environments for which organisms are optimized, but their roles are often opaque. One classic example is pitch perception, whose properties are commonly linked to peripheral neural coding limits rather than environmental acoustic constraints. We trained artificial neural networks to estimate fundamental frequency from simulated cochlear representations of natural sounds. The best-performing networks replicated many characteristics of human pitch judgments. To probe how our ears and environment shape these characteristics, we optimized networks given altered cochleae or sound statistics. Human-like behavior emerged only when cochleae had high temporal fidelity and when models were optimized for natural sounds. The results suggest pitch perception is critically shaped by the constraints of natural environments in addition to those of the cochlea, illustrating the use of contemporary neural networks to reveal underpinnings of behavior. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.18.389346v1?rss=1 Authors: Wang, S.-F., Carr, V. A., Favila, S. E., Bailenson, J. N., Brown, T. I., Jiang, J., Wagner, A. D. Abstract: The hippocampus (HC) and surrounding medial temporal lobe (MTL) cortical regions play a critical role in spatial navigation and episodic memory. However, it remains unclear how the interaction between the hippocampal conjunctive coding and mnemonic differentiation contributes to neural representations of spatial environments. Multivariate functional magnetic resonance imaging (fMRI) analyses enable examination of how human HC and MTL cortical regions encode multidimensional spatial information to support memory-guided navigation. We combined high-resolution fMRI with a virtual navigation paradigm in which participants relied on memory of the environment to navigate to goal locations in two different virtual rooms. Within each room, participants were cued to navigate to four learned locations, each associated with one of two reward values. Pattern similarity analysis revealed that when participants successfully arrived at goal locations, activity patterns in HC and parahippocampal cortex (PHC) represented room-goal location conjunctions and activity patterns in HC subfields represented room-reward-location conjunctions. These results add to an emerging literature revealing hippocampal conjunctive representations during goal-directed behavior. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.16.384289v1?rss=1 Authors: Lorenzi, E., Lemaire, B. S., Versace, E., Matsushima, T., Vallortigara, G. Abstract: For inexperienced brains, some stimuli are more attractive than others. Human neonates and newly-hatched chicks preferentially orient towards face-like stimuli, biological motion, and objects changing speed. In chicks, this enhances exposure to social partners, and subsequent attachment trough filial imprinting. Early preferences are not steady. The preference for stimuli changing speed fades away after three days in chicks. To understand the physiological mechanisms underlying these transient responses, we tested whether the early preferences for objects changing speed can be promoted by thyroid hormone 3,5,3'-triiodothyronine (T3). This hormone determines the start of imprinting's sensitive period. We found that the preference for objects changing speed can be re-established in female chicks treated with T3. Moreover, day-one chicks treated with an inhibitor of endogenous T3 did not show any preference. These results suggest that the time windows of early predispositions and of high plasticity are controlled by the same molecular mechanisms. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.15.383364v1?rss=1 Authors: Rodriguez, C., Fusani, L., Raboisson, G., Hödl, W., Ringler, E., Canoine, V. Abstract: Territorial behaviour has been widely described across many animal taxa, where the acquisition and defence of a territory are critical for the fitness of an individual. Extensive evidence suggests that androgens (e.g. testosterone) are involved in the modulation of territorial behaviour in male vertebrates. Short-term increase of androgen following a territorial encounter appears to favour the outcome of a challenge. The "Challenge Hypothesis" proposed by Wingfield and colleagues outlines the existence of a positive feedback relationship between androgen and social challenges (e.g. territorial intrusions) in male vertebrates. Here we tested the challenge hypothesis in the highly territorial poison frog, Allobates femoralis, in its natural habitat by exposing males to simulated territorial intrusions in form of acoustic playbacks. We quantified repeatedly androgen concentrations of individual males via a non-invasive water-borne sampling approach. Our results show that A. femoralis males exhibited a positive behavioural and androgenic response after being confronted to simulated territorial intrusions, providing support for the Challenge Hypothesis in a territorial frog. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.16.384503v1?rss=1 Authors: Yang, C., Feeney, W. E. Abstract: Social learning is a mechanism by which behaviors can rapidly disseminate throughout a population. Rejection of foreign eggs is a key defense in hosts of avian brood parasites; however, whether social cues can inform whether a host rejects an egg remains unknown. Here, we aimed to determine whether access to social information can influence egg rejection behavior in semi-colonial barn swallows (Hirundo rustica). By manipulating the social information available from a neighboring nest, we found that swallows that had access to social information (i.e. neighbor recently rejected an egg) were more likely to reject a foreign egg compared to those that did not have access to social information (i.e. neighbor did not reject an egg). This result provides the first empirical evidence that egg rejection behaviors can solely be informed by social information, and in doing so highlights the dynamic nature of defenses that hosts can deploy against brood parasitism. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.16.385930v1?rss=1 Authors: Mason, D., Zajitschek, S., Anwer, H., O'Dea, R., Hesselson, D., Nakagawa, S. Abstract: Aversive learning, avoiding certain situations based on negative experiences, can profoundly increase fitness in animal species. The extent to which this cognitive mechanism could evolve depends upon individual differences in aversive learning being stable through time, and heritable across generations, yet no published study has quantified the stability of individual differences in aversive learning using the repeatability statistic, R (also known as the intra-class correlation). We assessed the repeatability of aversive learning by conditioning approximately 100 zebrafish (Danio rerio) to avoid a colour cue associated with a mild electric shock. Across eight different colour conditions zebrafish did not show consistent individual differences in aversive learning (R = 0.04). Within conditions, when zebrafish were twice conditioned to the same colour, blue conditioning was more repeatable than green conditioning (R = 0.15 and R = 0.02). In contrast to the low repeatability estimates for aversive learning, zebrafish showed moderately consistent individual differences in colour preference during the baseline period (i.e. prior to aversive conditioning; R {approx} 0.45). Overall, aversive learning responses of zebrafish were weak and variable (difference in time spent near the aversive cue

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.16.385286v1?rss=1 Authors: Montes-Lourido, P., Kar, M., Kumbam, I., Sadagopan, S. Abstract: Estimates of detection and discrimination thresholds are often used to explore broad perceptual similarities between human subjects and animal models. Pupillometry shows great promise as a non-invasive, easily-deployable method of comparing human and animal thresholds. Using pupillometry, previous studies in animal models have obtained threshold estimates to simple stimuli such as pure tones, but have not explored whether similar pupil responses can be evoked by complex stimuli, what other stimulus contingencies might affect stimulus-evoked pupil responses, and if pupil responses can be modulated by experience or short-term training. In this study, we used an auditory oddball paradigm to estimate detection and discrimination thresholds across a wide range of stimuli in guinea pigs. We demonstrate that pupillometry yields reliable detection and discrimination thresholds across a range of simple (tones) and complex (conspecific vocalizations) stimuli; that pupil responses can be robustly evoked using different stimulus contingencies (low-level acoustic changes, or higher level categorical changes); and that pupil responses are modulated by short-term training. These results lay the foundation for using pupillometry as a high-throughput method of estimating thresholds in large experimental cohorts, and unveil the full potential of using pupillometry to explore broad similarities between humans and animal models. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.13.378257v1?rss=1 Authors: Gottschalk, G., Keating, J. F., Kesler, K., Knox, K., Roy, A. Abstract: Abstract: Previously, we have demonstrated that ACIS KEPTIDE, a chemically modified peptide, selectively binds to ACE-2 receptor and prevents the entry of SARS-CoV2 virions in vitro in primate kidney Cells. However, it is not known if ACIS KEPTIDE attenuates the entry of SARS-CoV2 virus in vivo in lung and kidney tissues, protects health, and prevent death once applied through intranasal route. In our current manuscript, we demonstrated that the intranasal administration of SARS-CoV2 (1*106) strongly induced the expression of ACE-2, promoted the entry of virions into the lung and kidney cells, caused acute histopathological toxicities, and mortality (28%). Interestingly, thirty-minutes of pre-treatment with 50 g/Kg Body weight ACIS normalized the expression of ACE-2 via receptor internalization, strongly mitigated that viral entry, and prevented mortality suggesting its prospect as a prophylactic therapy in the treatment of COVID-19. On the contrary, the peptide backbone of ACIS was unable to normalize the expression of ACE-2, failed to improve the health vital signs and histopathological abnormalities. In summary, our results suggest that ACIS is a potential vaccine-alternative, prophylactic agent that prevents entry of SARS-CoV2 in vivo, significantly improves respiratory health and also dramatically prevents acute mortality in K18-hACE2 humanized mice. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.14.382622v1?rss=1 Authors: Vandaele, Y., Lenoir, M., Vouillac-Mendoza, C., Guillem, K., Ahmed, S. H. Abstract: Investigating the decision-making mechanisms underlying choice between drug and nondrug rewards is essential to understand how their alterations can contribute to substance use disorders. However, despite some recent effort, this investigation remains a challenge in a drug choice setting, notably when it comes to delineate the role of goal-directed versus habitual control mechanisms. The goal of this study was to try probing these different mechanisms by comparing response latencies measured during sampling (i.e., only one option is available) and choice trials. A deliberative goal-directed control mechanism predicts a lengthening of latencies during choice whereas a habitual control mechanism predicts no change in latencies. Alternatively, a race-like response competition mechanism, such as that postulated by the behavioral ecology-inspired Sequential Choice Model (SCM), predicts instead a shortening of response latencies during choice compared to sampling. Here we tested the predictions of these different mechanisms by conducting a systematic retrospective analysis of all cocaine versus saccharin choice experiments conducted in rats in our laboratory over the past 12 years. Overall, we found that rats engage a deliberative goal-directed mechanism after limited training, but shift to a SCM-like response selection mechanism after more extended training. The latter finding suggests that habitual control is engaged in a choice setting via a race-like response competition mechanism, and thus, that the SCM is not a general model of choice, as formulated initially, but a specific model of habitual choice. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.13.381996v1?rss=1 Authors: O'Bryan, L. R., Lambeth, S. P., Schapiro, S. J., Wilson, M. L. Abstract: Food-associated calls have attracted much research attention due to their potential to refer to discovered food in a word-like manner. Nevertheless, their effect on receiver behavior remains unclear for many species. While some studies suggest that food-associated calls attract other foragers, other studies indicate that they repel others. We conducted playback studies to differentiate between these two hypotheses for the function of the chimpanzee (Pan troglodytes) food-associated "rough grunt". We tested how acoustic playbacks of rough grunts (or control calls) from one of two known, identical food patches affected receivers' foraging decisions in a captive setting. We found that participants were more likely than chance to first investigate the patch from which rough-grunts, but not control calls, were broadcast. However, neither condition increased the likelihood that participants fed first from a given patch. Our results support the hypothesis that rough-grunts attract receivers. However, since receivers were already aware of the presence of food, our results question whether rough-grunts attract by conveying information about discovered food, or rather, the signaler's motivational state. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.14.382507v1?rss=1 Authors: Finkbeiner, S. D., Briscoe, A. D. Abstract: True color vision in animals is achieved when wavelength discrimination occurs based on chromatic content of the stimuli, regardless of intensity. In order to successfully discriminate between multiple wavelengths, animals must use at least two photoreceptor types with different spectral sensitivity peaks. Heliconius butterflies have duplicate UV opsin genes, which encode two kinds of photoreceptors with peak sensitivities in the ultraviolet and violet, respectively. In H. erato, the ultraviolet photoreceptor is only expressed in females. Evidence from intracellular recordings suggests female H. erato may be able to discriminate between UV wavelengths, however, this has yet to be tested experimentally. Using an arena with a controlled light setting, we tested the ability of H. erato, and two species lacking the violet receptor, H. melpomene and outgroup Eueides isabella, to discriminate between two ultraviolet wavelengths, 380 and 390 nm, as well as two blue wavelengths, 400 and 436 nm, after being trained to associate each stimulus with a food reward. Wavelength stimuli were presented in varying intensities to rule out brightness as a cue. We found that H. erato females were the only butterflies capable of color vision in the UV range; the other butterflies had an intensity-dependent preference for UV stimuli. Across species, both sexes showed color vision in the blue-range. Models of H. erato color vision suggest that females have an advantage over males in discriminating the inner UV-yellow corolla of Psiguria pollen flowers from the surrounding outer orange petals, while previous models (McCulloch et al. 2017) suggested that H. erato males have an advantage over females in discriminating Heliconius 3-hyroxykynurenine (3-OHK) yellow wing coloration from non-3-OHK yellow wing coloration found in mimics. These results provide some of the first behavioral evidence for UV color discrimination in Heliconius females in the context of foraging, lending support to the hypothesis (Briscoe et al. 2010) that the duplicated UV opsin genes function together in UV color vision. Taken together, the sexually dimorphic visual system of H. erato appears to have been shaped by both sexual selection and sex-specific natural selection. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.12.380683v1?rss=1 Authors: Ruland, M., Andirko, A., Romanowska, I., Boeckx, C. Abstract: A central question in the evolution of human language is whether it emerged as a result of one specific event or from a mosaic-like constellation of different phenomena and their interactions. Three potential processes have been identified by recent research as the potential primum mobile for the origins of modern linguistic complexity: Self-domestication, characterized by a reduction in reactive aggression and often associated with a gracilization of the face; changes in early brain development manifested by globularization of the skull; and demographic expansion of H.~sapiens during the Middle Pleistocene. We developed an agent-based model to investigate how these three factors influence transmission of information within a population. Our model shows that there is an optimal degree of both hostility and mental capacity at which the amount of transmitted information is the largest. It also shows that linguistic communities formed within the population are strongest under circumstances where individuals have high levels of cognitive capacity available for information processing and there is at least a certain degree of hostility present. In contrast, we find no significant effects related to population size. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.13.379719v1?rss=1 Authors: Habedank, A., Urmersbach, B., Kahnau, P., Lewejohann, L. Abstract: Existing methods for analysis of home cage based preference tests are either time consuming, not suitable for group management, expensive and/or based on proprietary equipment that is not freely available. For this reason, we developed an automated system for group housed mice based on radio frequency identification: the Mouse Position Surveillance System (MoPSS). The system uses an Arduino microcontroller with compatible components, it is affordable and easy to rebuild for every laboratory. The MoPSS was validated using female C57BL/6J mice and manual video comparison. It proved to be accurate even for fast moving mice (up to 100 % accuracy after logical reconstruction), and is already implemented in several studies in our laboratory. Here, we provide the complete construction description as well as the validation data and the results of an example experiment. This tracking system will allow group-based preference testing with individually identified mice to be carried out in a convenient manner, creating the foundation for better housing conditions from the animals' perspective. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.13.381012v1?rss=1 Authors: Dubois, T., Pasquaretta, C., Barron, A., Gautrais, J., Lihoreau, M. Abstract: Central place foraging pollinators tend to develop multi-destination routes (traplines) to exploit several patchily distributed plant resources. While the formation of traplines by individual pollinators has been studied in details, how populations of individuals exploit resources in a common area is an open ques-tion difficult to address experimentally. Here we explored conditions for the emergence of resource partitioning among traplining bees using agent-based models built from experimental data of bumble-bees foraging on artificial flowers. In the models, bees learn to develop routes as a consequence of feedback loops that change their probabilities of moving between flowers. While a positive reinforce-ment of route segments leading to rewarding flowers is sufficient for the emergence of resource parti-tioning when flowers are evenly distributed, a negative reinforcement of route segments leading to un-rewarding flowers is necessary when flowers are patchily distributed. In these more complex environ-ments, the negative experiences of individual bees favour the spatial segregation of foragers and high levels of collective foraging efficiency. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.11.377788v1?rss=1 Authors: Habedank, A., Kahnau, P., Lewejohann, L. Abstract: In rodents, the T-maze test is commonly used to investigate spontaneous alternating behaviour but it can also be used to investigate memory, stimuli discrimination or preference between goods. However, especially regarding T-maze preference tests there is no recommended protocol and researchers frequently report reproduction difficulties of this test using mice. Here, we aimed to develop an efficient protocol with female C57BL/6J mice, conducting two preference tests with different design: In a first test, on two consecutive days with five trials, thirteen mice had to choose between two fluids. In a second preference test, on five consecutive days with two (week 1) or three (week 2) trials, twelve mice had to choose between one arm containing bedding mixed with millet and one containing only bedding. This test design resembled a simple learning test (learn where to find the rewarded and the unrewarded arm on the basis of spatial, olfactory and visual cues). In both experiments, mice took only a few seconds per trial to run the maze and make their choice. However, in both experiments mice failed to show any preference for one of the arms. Instead, they alternated choices. We therefore believe the T-maze test to be rather unsuitable to test preference or learning behaviour with C57BL/6J mice. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.09.374025v1?rss=1 Authors: Tontini, J. F., Poli, C. H. E. C., Hampel, V. d. S., Farias, M. d. S., Fajardo, N. M., Silva, J. A. d., Farinatti, L. H. E., Muir, J. P., Jalise Fabiola Tontini, Cesar Henrique Espirito Candal Poli, Viviane da Silva Hampel Abstract: Tropical sward characteristics can alter lamb ingestive behavior. Our study evaluated the ingestive behavior of young lambs in different tropical pastures to identify which variables interfere in their grazing activity. Two years of study were carried out with 54 weaned lambs distributed in three different swards: 1) monoculture of a upright grass, guinea grass (Panicum maximum; GG); 2) monoculture of a shrubby legume pigeon pea (Cajanus cajan; PP) and 3) contiguous areas with half the paddock with GG and half with PP (GP). The experiment was set out in a randomized complete block design. Lamb ingestive behavior was observed from sunrise to sunset with records every 5 minutes. To identify the main variables that affected with the lamb grazing activity, a multivariate analysis of the Decision Tree was performed. Our results showed that there was no difference in the ingestive behavior parameters of young lambs in different swards (P > 0.05). There was interaction among the swards and the experimental periods for the variables idleness time and biting rate (P [≤] 0.05). Grazing time of the animals increased 40% with experimental period progression. The Decision Tree identified leaf:stem ratio as the variable that most influenced lamb grazing time in GG and GP swards while in the PP sward grazing time was directly related to the pasture height. The behavior of young lambs on tropical pasture is variable as there is a change in the behavioral response over time. In addition, the grazing time of these animals can be estimated by means of variables related to pasture structural characteristics (leaf:stem ratio and height) together with chemical variables. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.09.373993v1?rss=1 Authors: Luo, H., Wang, Q., Wang, L. Abstract: Aims In the present research, we assessed the therapeutic effects of Exendin-4 (Ex-4) on rat models with spinal cord injury (SCI). Materials and methods 36 male Sprague-Dawley rats were randomly allocated into three groups, including sham operation group, SCI group and SCI+Ex-4 group (Ex-4 treatment (10 {micro}g/rat) after SCI, i.p.). In the SCI group, a laminectomy was performed at the T10 vertebrae, followed by weight-drop contusion of the spinal cord. In the sham group, a laminectomy was carried out without SCI contusion. Key findings Our results showed that Basso-Beattie-Bresnahan scale scores were significantly decreased after SCI, and were obviously improved in SCI rats with Ex-4 administration. Additionally, the water content of spinal cord in SCI group was dramatically increased than that in sham group, and after Ex-4 treatment, degree of edema of spinal cord was remarkably reduced. And also, concentration levels of inflammatory cytokines (IL-1, IL-1{beta}, IL-6 and TNF-) in the spinal cord were significantly elevated after SCI, and were remarkably reduced in SCI rats with Ex-4 administration. Subsequently, cell apoptosis rate in the injured spinal cord was significantly increased, and after Ex-4 treatment, cell apoptosis rate was remarkably decreased. We also revealed that levels of PCBP2 mRNA and protein were significantly up-regulated after SCI, and were dramatically dropped in SCI rats with Ex-4 administration. Significance Take altogether, our findings disclosed that Ex-4 plays a role in promoting neurological function recovery and inhibiting neuronal apoptosis through effecting PCBP2 expression in SCI rat models. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.06.370023v1?rss=1 Authors: Schmidt, K. T., Sharp, J. L., Ethridge, S. B., Pearson, T., Ballard, S., Potter, K. M., Smith, M. A. Abstract: Heroin intake decreases during the proestrus phase of the estrous cycle in female, Long-Evans rats. The purpose of this study was to (1) determine if proestrus-induced decreases in heroin intake extend across rat strains and (2) determine if proestrus-induced decreases in responding extend to a nondrug reinforcer. Female rats were implanted with intravenous catheters and trained to self-administer heroin. Estrous cycle was tracked daily for the duration of the study. During testing, Lewis, Sprague-Dawley, and Long Evans rats self-administered low (0.0025 mg/kg) and high (0.0075 mg/kg) doses of heroin (Experiment 1) and then self-administered sucrose (Experiment 2) on fixed ratio (FR1) schedules of reinforcement. Heroin intake decreased significantly during proestrus in all three rat strains under at least one dose condition; however, sucrose intake did not decrease during proestrus in any strain. These data indicate that responding maintained by heroin, but not a nondrug reinforcer, significantly decreases during proestrus in female rats and that these effects are consistent across rat strain. Keywords: opioid; proestrus; reinforcement; self-administration Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.06.371567v1?rss=1 Authors: Dakin, R., Clunis, P., Ryder, T. B. Abstract: Social reciprocity is thought to be the most important driver of cooperation among non-kin, but its effects on complex social networks in the wild have not been studied. Here, we test whether reciprocation can explain social dynamics in a cooperative bird, the wire-tailed manakin (Pipra filicauda). Over three years of study, we observed that territory holding males engaged in far more reciprocated (bidirectional) partnerships with other territory holders than expected by chance. Reciprocated partnerships were also stronger (i.e., the partners interacted more frequently) than non-reciprocated partnerships, controlling for spatial proximity. Furthermore, we show that a male's social contribution to a given partner was predictive of the number of social interactions he received from that same partner. Finally, we show that reciprocation predicted the long-term stability of a partnership one year later. Together, these results demonstrate that reciprocity can stabilize cooperation within a broader social network. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.05.368035v1?rss=1 Authors: da Costa, F. P., Arruda, M. d. F., Ribeiro, K., Pessoa, D. M. A. Abstract: The giant river prawn ( Macrobrachium rosenbergii ), native to rivers and river mouths of different Asian countries, is a heavily widespread species that has been introduced around the world due to its great commercial importance. These prawns are farmed under many different conditions that might translate to a great range of light environments, which impact their behavior and productivity. Here, as a contribution for prawns' welfare and economical productivity, we present the first study employing both visual modeling and behavioral data to evaluate ontogenetic changes on color preference of juveniles and adults of M. rosenbergii. For this purpose, we offered ten shelters of different colors to juveniles and adults and registered their preference. Our results showed that the criterion for shelter preference changed with ontogeny, since juveniles chose shelters based on chromaticity (preference for blue), while adults based their decisions on brightness (preference for dark gray). This preference of adults for dark colors is probably associated with a light avoidance behavior. We recommend providing blue shelters for juveniles and dark shelters for adults. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.04.367912v1?rss=1 Authors: Khanal, P., Devkota, N., Dahal, M., Paudel, K., Mishra, S. R., Joshi, D. Abstract: Background : Health workers involved in COVID-19 response might be at risk of developing fear and psychological distress. This study aimed to identify factors associated with COVID-19 fear among health workers in Nepal during the early phase of pandemic. Methods : A web-based cross-sectional survey was conducted in the month of April-May 2020 among 475 health workers directly involved in COVID-19 management. The Fear Scale of COVID 19 (FCV-19S) was used to measure the status of fear. Scatter plots were used to observe the relationship between fear and other psychological outcomes: anxiety, depression and insomnia. Multivariable logistic regression was done to identify factors associated with COVID fear. Results: COVID-19 fear score was moderately correlated with anxiety and depression, and weakly correlated with insomnia (p

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.02.365411v1?rss=1 Authors: Emberts, Z., Wiens, J. J. Abstract: 1. In many animal species, individuals engage in fights with conspecifics over access to limited resources (e.g. mates, food, or shelter). Most theory about these intraspecific fights assumes that damage has an important role in determining the contest winner. Thus, defensive structures that reduce the amount of damage an individual accrues during intraspecific competition should provide a fighting advantage. 2. Examples of such damage-reducing structures include the dermal shields of goats, the dorsal osteoderms of crocodiles, and the armored telsons of mantis shrimps. Although numerous studies have identified these defensive structures, no study has investigated whether they influence the outcomes of intraspecific fights. 3. Here, we investigated whether inhibiting damage by enhancing an individual's armor influenced fighting behavior and success in the giant mesquite bug, Thasus neocalifornicus (Insecta: Hemiptera: Coreidae). 4. We found that experimentally manipulated individuals (i.e. those provided with additional armor) were 1.6 times more likely to win a fight when compared to the control. These results demonstrate that damage, and damage-reducing structures, can influence fighting success. 5. The implications of these results are twofold. First, our results experimentally support a fundamental assumption of most theoretical fighting models: that damage is a fighting cost that can influence contest outcomes. Second, these results highlight the importance of an individual's defensive capacity, and why defense should not be ignored. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.02.364422v1?rss=1 Authors: Naniwa, K., Aonuma, H. Abstract: The cricket is one of the model animals used to investigate the neuronal mechanisms underlying adaptive locomotion. An intact cricket walks with a tripod gait, similar to other insects. The motor control center of the leg movements is located in the thoracic ganglia. In this study, we investigated the walking gait patterns of crickets whose ventral nerve cords were surgically cut to gain an understanding of how the descending signals from the head ganglia and ascending signals from the abdominal nervous system into the thoracic ganglia mediate the initiation and coordination of the walking gait pattern. Crickets whose paired connectives between the brain and subesophageal ganglion (SEG) were cut exhibited a tripod gait pattern. However, when one side of the connectives between the brain and SEG was cut, the crickets continued to turn in the opposite direction to the connective cut. Crickets whose paired connectives between the SEG and prothoracic ganglion were cut did not walk, whereas the crickets exhibited an ordinal tripod gait pattern when one side of the connectives was intact. Crickets whose paired connectives between the metathoracic ganglion and abdominal ganglia were cut initiated walking, although the gait was not a coordinated tripod pattern, whereas the crickets exhibited a tripod gait when one side of the connectives was intact. These results suggest that the brain plays an inhibitory role in initiating leg movements, and that both the descending signals from the head ganglia and the ascending signals from the abdominal nervous system are both important in initiating and coordinating insect walking gait patterns. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.03.366195v1?rss=1 Authors: Sclocco, A., Ong, S. J. Y., Pyay Aung, S. Y., Teseo, S. Abstract: Automatic video tracking has become a standard tool for investigating the social behavior of insects. The recent integration of computer vision in tracking technologies will likely lead to fully automated behavioral pattern classification within the next few years. However, most current systems rely on offline data analysis and use computationally expensive techniques to track pre-recorded videos. To address this gap, we developed BACH (Behavior Analysis maCHine), a software that performs video tracking of insect groups in real time. BACH uses object recognition via convolutional neural networks and identifies individually tagged insects via an existing matrix code recognition algorithm. We compared the tracking performances of BACH and a human observer across a series of short videos of ants moving in a 2D arena. We found that, concerning computer vision-based ant detection only, BACH performed only slightly worse than the human observer. Contrarily, individual identification only attained human-comparable levels when ants moved relatively slow, and fell when ants walked relatively fast. This happened because BACH had a relatively low efficiency in detecting matrix codes in blurry images of ants walking at high speeds. BACH needs to undergo hardware and software adjustments to overcome its present limits. Nevertheless, our study emphasizes the possibility of, and the need for, integrating real time data analysis into the study of animal behavior. This will accelerate data generation, visualization and sharing, opening possibilities for conducting fully remote collaborative experiments. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.11.02.361840v1?rss=1 Authors: Munoz, M. I., Halfwerk, W. Abstract: Signal detection is a minimum requirement for any communicative interaction. Acoustic signals, however, often experience amplitude losses during their transmission through the environment, reducing their detection range. Displaying from sites that increase the amplitude of the sound produced, such as cavities or some reflective surfaces, can improve the detectability of signals by distant receivers. Understanding how display sites influence sound production is, however, far from understood. We measured the effect of leaf calling sites on the calls of an arboreal (Hyalinobatrachium fleischmanni) and a leaf-litter specialist (Silverstoneia flotator) frog species. We collected the leaves where males of both species were observed calling, and conducted playback experiments to measure their effect on the amplitude of frog calls. Overall, the leaves used by H. fleischmanni and S. flotator were of similar dimensions, and amplified the calls of each species by about 5.0 and 2.5 dB, respectively. The degree of call amplification was unrelated to leaf dimensions or the position of the frogs on the leaves, but explained by the different frequency content of the calls of each species. Depending on the spatial location of intended and unintended receivers, we suggest that amplification of frog calls by leaves could represent either a benefit or impose costs for arboreal and terrestrial species. We argue that the microhabitat of the substrate from which animals display needs to be considered when addressing signal evolution. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.31.354605v1?rss=1 Authors: Goto, Y., Yoda, K., Weimerskirch, H., Sato, K. Abstract: Extinct large volant birds and pterosaurs are thought to have used wind dependent soaring flight, similar to modern large birds. There are two types of soaring: thermal soaring, used by condors and frigatebirds, which involves the use of updrafts to ascend and then glide horizontally; and dynamic soaring, used by albatrosses, which involves the use of differences in wind speed with height above the sea surface. However, it is controversial which soaring styles were used by extinct species. In this study, we used aerodynamic models to comprehensively quantify and compare the soaring performances and wind conditions required for soaring in two of the largest extinct bird species, Pelagornis sandersi and Argentavis magnificens (6-7 m wingspans), two pterosaur species, Pteranodon (6 m wingspan) and Quetzalcoatlus (10 m wingspans), and extant soaring birds. For dynamic soaring, we quantified how fast the animal could fly and how fast it could fly upwind. For thermal soaring, we quantified the animal's sinking speed circling in a thermal at a given radius and how far it could glide losing a given height. Consistently with previous studies, our results suggest that Pteranodon and Argentavis used thermal soaring. Conversely, the results suggest that Quetzalcoatlus, previously thought to have used thermal soaring, was less able to ascend in updrafts than extant birds, and Pelagornis sandersi, previously thought to have used dynamic soaring, actually used thermal soaring. Our results demonstrate the need for a comprehensive assessment of performance and required wind conditions when estimating soaring styles of extinct flying species. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.30.362806v1?rss=1 Authors: Saveer, A. M., DeVries, Z. C., Santangelo, R., Schal, C. Abstract: Adaptive insect behavior is subject to modulation by internal physiological states and external social contexts to enhance reproductive fitness and survival. The common bed bug, Cimex lectularius is an obligate hematophagous ectoparasite that requires host blood for growth, development, and reproduction. We investigated how mating, starvation and social factors such as harassment by males affect host-seeking, blood feeding, oviposition, and survival of female bed bugs. The percentage of females that fed and the amount of blood they ingested were greater in mated females (90 to 100%) than in unmated females (48 to 60%). Mating state also modulated the females orientation towards human skin odor in an olfactometer; more mated (69%) than unmated (23%) females responded to human odors. The response rate of unmated females (60%) to human odor increased with longer starvation period, while the opposite pattern was observed in mated females (20%). Although fecundity after a single blood meal was unaffected by long or short residence with males, females subjected to frequent copulations had lower survivorship and lifespan than females subjected to males for only 24 h. Taken together, these results indicate that behaviors are adaptively expressed based on the internal physiological state to maximize survival and reproductive fitness. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.30.362137v1?rss=1 Authors: Suda, N., Cendejas-Hernandez, J., Poulton, J., Jones, J. P., Konsoula, Z., Smith, C., Parker, W. Abstract: Based on several lines of evidence, numerous investigators have suggested that paracetamol exposure during early development can induce neurological disorders. We had previously postulated that paracetamol exposure early in life, if combined with antioxidants that prevent accumulation of NAPQI, the toxic metabolite of paracetamol, might be innocuous. In this study, we administered paracetamol at or below the currently recommended therapeutic dose to male laboratory rat pups aged 4-10 days. The antioxidants cysteine and mannitol were included to prevent accumulation of NAPQI. In addition, animals were exposed to a cassette of common stress factors: an inflammatory diet, psychological stress, antibiotics, and mock infections using killed bacteria. At age 37-49 days, observation during introduction to a novel conspecific revealed increased rearing behavior, an asocial behavior, in animals treated with paracetamol plus antioxidants, regardless of their exposure to oxidative stress factors (2-way ANOVA; P < 0.0001). This observation would suggest that the initial hypothesis is incorrect, and that oxidative stress mediators do not entirely eliminate the effects of paracetamol on neurodevelopment. This study provides additional cause for caution when considering the use of paracetamol in the pediatric population, and provides evidence that the effects of paracetamol on neurodevelopment need to be considered both in the presence and in the absence of oxidative stress. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.28.358978v1?rss=1 Authors: Nambyiah, P., Brown, A. E. Abstract: Background: Vertebrate animal experiments have suggested that anaesthesia exposure to the developing nervous system causes neuroapoptosis and behavioural impairment. Mechanistic understanding is limited, and target-based approaches are challenging. High-throughput methods may be an important parallel approach to drug-discovery and mechanistic research. The nematode worm Caenorhabditis elegans is an ideal candidate as a model for this. A rich subset of its behaviour can be studied, and hundreds of morphological and behavioural features can be quantified, then aggregated to yield a 'signature'. Perturbation of this behavioural signature may provide a tool that can be used to quantify the effects of anaesthetic regimes, and act as an outcome marker for drug screening and molecular target research. Methods. Larval C. elegans were exposed to: isoflurane, ketamine, morphine, dexmedetomidine, and lithium (and combinations). Behaviour was recorded, and videos analysed with automated algorithms to extract behavioural and morphological features. Results: Anaesthetic exposure during early development leads to persisting morphological and behavioural variation (in total, 125 features/exposure combinations). Higher concentrations, and combinations of isoflurane with ketamine, lead to more feature 'hits'. Morphine and dexmedetomidine do not appear to lead to behavioural impairment. Lithium rescues the neurotoxic phenotype produced by isoflurane. Conclusions: Findings correlate well with vertebrate research: impairment is dependent on agent, is concentration-specific, is more likely with combination therapies, and can potentially be rescued by lithium. These results suggest that C. elegans may be an appropriate model with which to pursue phenotypic screens for drugs that mitigate the neurobehavioural impairment. Some possibilities are suggested for how high-throughput platforms might be organised in service of this field. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.28.358994v1?rss=1 Authors: Ruiz-Raya, F., Ibanez-Alamo, J. D., Parenteau, C., Chastel, O., Soler, M. Abstract: Even though adaptations resulting from co-evolutionary interactions between avian brood parasites and their hosts have been well studied, the hormonal mechanisms underlying behavioural host defences remain largely unexplored. Prolactin, the main hormone mediating avian parental behaviour, has been hypothesized to play a key role in the orchestration of host responses to brood parasitic eggs. Based on the positive association between plasma prolactin and parental attachment to eggs, decreasing levels of this hormone are expected to facilitate egg-rejection decisions in parasitized clutches. We tested this prediction by implanting Eurasian blackbirds (Turdus merula) females with an inhibitor of prolactin secretion, bromocriptine mesylate, to experimentally low their prolactin levels. We found that bromocriptine-treated females rejected mimetic model eggs at higher rates than placebo-treated individuals. To our knowledge, this is the first experimental evidence that host responses to brood parasitism are mediated by the primary endocrine pathway that orchestrates the expression of avian parental care. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.27.357764v1?rss=1 Authors: Wascher, C. A. F., Allen, K., Szipl, G. Abstract: Cognitive abilities allow animals to navigate through complex, fluctuating environments. For example, behavioural flexibility, which is the ability of an animal to alter their behaviour in response to a novel stimulus or to modify responses to as familiar stimulus or behavioural inhibition, defined as the ability to control a response in order to choose a conflicting course of action. Behavioural flexibility and inhibitory control are expected to vary between and within species based on socio-ecological factors. In the present study we compared performance of a captive group of eight crows, Corvus corone, and ten domestic fowl, Gallus gallus domesticus, in two cognitive tasks, the cylinder task as a test of motor inhibitory control, and reversal learning as a measure of learning ability and behavioural flexibility. Four crows and nine fowl completed the cylinder task, eight crows completed the reversal learning experiment and nine fowl were tested in the acquisition phase, however three fowl did not complete the reversal phase of the experiment due to time constraints. Crows performed significantly better in the cylinder task compared to domestic fowl. In the reversal learning experiment, species did not significantly differ in the number of trials until learning criterion was reached. In crows, individuals who needed less trials to reach learning criterion in the acquisition phase also needed less trials to reach the criterion in the reversal phase. This relationship was lacking in domestic fowl. Performance in the learning task did not correlate with performance in the cylinder task in domestic fowl. Our results show crows to possess significantly better motor-inhibitory control compared to domestic fowl, which could be indicative of this specific aspect of executive functioning to be lacking in domestic fowl. In contrast learning performance in a reversal learning task did not differ between crows and domestic fowl, indicating similar levels of behavioural flexibility in both species. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.27.355032v1?rss=1 Authors: Barnes, L., Petit, S., Badcock, N. A., Whyte, C., Woolgar, A. Abstract: Measuring cognition in single subjects presents unique challenges. Yet individually sensitive measurements offer extraordinary opportunities, from informing theoretical models to enabling truly individualised clinical assessment. Here, we test the robustness of fast, periodic, visual stimulation (FPVS), an emerging method proposed to elicit detectable responses to written words in the electroencephalogram (EEG) of individual subjects. The method is non-invasive, passive, and requires only a few minutes of testing, making it a potentially powerful tool to test comprehension in those who do not speak or who struggle with long testing procedures. In an initial study, Lochy et al. (2015) used FPVS to detect word processing in 8 out of 10 fluent French readers. Here, we attempted to replicate their study in a new sample of ten fluent English readers. Participants viewed rapid streams of pseudo-words with words embedded at regular intervals, while we recorded their EEG. Based on Lochy et al., we expected that words would elicit a steady-state response at the word-presentation frequency (2 Hz) over parieto-occipital electrode sites. However, across 40 datasets (10 participants, two conditions, and two regions of interest - ROIs), only four datasets met the criteria for a unique response to words. This corresponds to a 10% detection rate. We conclude that FPVS should be developed further before it can serve as an individually-sensitive measure of written word processing. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.27.354845v1?rss=1 Authors: Traynor, K. S., Lamas, Z. S., vanEngelsdorp, D. Abstract: Eusocial Apis mellifera colonies depend on queen longevity and brood viability to survive, as the queen is the sole reproductive individual and the maturing brood replenishes the shorter lived worker bees. Production of many crops rely on both pesticides and bee pollination to improve crop quantity and quality. We looked at the resiliency of queens and their brood after one month of sublethal exposure to field relevant doses of pesticides that mimic exposure during commercial pollination contracts. We exposed full size colonies to pollen contaminated with field-relevant doses of the fungicides (chlorothalonil and propicanizole), insecticides (chlorypyrifos and fenpropathrin) or both, noting a significant reduction in pollen consumption in colonies exposed to fungicides compared to control. While we found no difference in the total amount of pollen collected per colony, a higher proportion of pollen to non-pollen foragers was detected in all pesticide exposed colonies. After ceasing treatments we measured brood development, discovering a significant increase in brood loss and/or cannibalism across all pesticide exposed groups. Sublethal pesticide exposure in general was linked to reduced production of replacement workers and a change in protein acquisition (pollen vs. non-pollen foraging). Fungicide exposure also resulted in increased loss of the reproductive queen. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.27.356535v1?rss=1 Authors: Zhu, L., Mangan, M., Webb, B. Abstract: Insects, despite relatively small brains, can perform complex navigation tasks such as memorising a visual route. The exact format of visual memory encoded by neural systems during route learning and following is still unclear. Here we propose that interconnections between Kenyon cells in the Mushroom Body (MB) could encode spatio-temporal memory of visual motion experienced when moving along a route. In our implementation, visual motion is sensed using an event-based camera mounted on a robot, and learned by a biologically constrained spiking neural network model, based on simplified MB architecture and using modified leaky integrate-and-fire neurons. In contrast to previous image- matching models where all memories are stored in parallel, the continu- ous visual flow is inherently sequential. Our results show that the model can distinguish learned from unlearned route segments, with some toler- ance to internal and external noise, including small displacements. The neural response can also explain observed behaviour taken to support sequential memory in ant experiments. However, obtaining comparable robustness to insect navigation might require the addition of biomimetic pre-processing of the input stream, and determination of the appropriate motor strategy to exploit the memory output. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.26.354258v1?rss=1 Authors: Nicholson, D., Prinz, A. A. Abstract: What limits our ability to find an object we are looking for? There are two competing models: one explains attentional limitations during visual search in terms of a serial processing computation, the other attributes limitations to noisy parallel processing. Both models predict human visual search behavior when applied to the simplified stimuli often used in experiments, but it remains unclear how to extend them to account for search of complex natural scenes. Models exist of natural scene search, but they do not predict whether a given scene will limit search accuracy. Here we propose an alternate mechanism to explain limitations across stimuli types: visual search is limited by an "untangling" computation, proposed to underlie object recognition. To test this idea, we ask whether models of object recognition account for visual search behavior. The current best-in-class models are artificial neural networks (ANNs) that accurately predict both behavior and neural activity in the primate visual system during object recognition tasks. Unlike dominant visual search models, ANNs can provide predictions for any image. First we test ANN-based object recognition models with simplified stimuli typically used in studies of visual search. We find these models exhibit a hallmark effect of such studies: a drop in target detection accuracy as the number of distractors increases. Further experiments show this effect results from learned representations: networks that are not pre-trained for object recognition can achieve near perfect accuracy. Next we test these models with complex natural images, using a version of the Pascal VOC dataset where each image has a visual search difficulty score, derived from human reaction times. We find models exhibit a drop in accuracy as search difficulty score increases. We conclude that ANN-based object recognition models account for aspects of visual search behavior across stimuli types, and discuss how to extend these results. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.26.350132v1?rss=1 Authors: Fouilloux, C., Fromhage, L., Valkonen, J. K., Rojas, B. Abstract: Aggression between juveniles can be unexpected, as their primary motivation is to survive until their reproductive stage. However, instances of aggression, which may escalate to cannibalism, can be vital for survival, although the factors (e.g. genetic or environmental) leading to cannibalism vary across taxa. While cannibalism can greatly accelerate individual growth, it may also reduce inclusive fitness when kin are consumed. As a solution to this problem, some cannibals demonstrate kin discrimination and preferentially attack unrelated individuals. Here, we used both experimental and modeling approaches to consider how physical traits (e.g. size in relation to opponent) and genetic relatedness mediate aggressive behavior in dyads of cannibalistic Dendrobates tinctorius tadpoles. We paired sibling, half-sibling, and non-sibling tadpoles of different sizes together in an arena and recorded their aggression and activity. We found that the interaction between size and relatedness predicts aggressive behavior: large non-siblings are significantly more aggressive than large siblings. Unexpectedly, although siblings tended to attack less overall, in size mismatched pairs they attacked faster than in non-sibling treatments. Ultimately, it appears that larval aggression reflects a balance between relatedness and size where individuals trade-off their own fitness with that of their relatives. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.26.354704v1?rss=1 Authors: wu, x., Feng, C., Zhang, S., Liang, Z., Dong, W., Qin, S., Luo, Y.-J., Liu, C. Abstract: Bullying events during adolescence are common, yet it remains largely unclear which kinds of behavioral patterns are more likely to result in being exploited. Leveraging recent advances in computational modeling and experimental economics, this study examines whether being nice or tough during early social interactions will impact future interactions. Adolescents were randomly assigned to play a cooperation game with two different simulated partners. We found that participants were more likely to cooperate with the initially tough partner than with the initially nice partner. Computational modeling revealed that behavioral changes were driven by changes in perceived social rewards from reciprocity. Perceived social rewards mediated the effects of different partners on the participants cooperative behaviors. The results indicate that being nice is not a good strategy for building social cooperation, and advance our knowledge of how adolescents form sustained social relationships with peers and may have implications for the education field. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.26.354852v1?rss=1 Authors: Dunbar, R. I. M., Shultz, S. Abstract: The capacity to inhibit prepotent actions (self-control) plays a potentially important role in many aspects of the behaviour of birds and mammals. A number of studies, for example, have used it as an index of foraging skills. Inhibition is, however, also crucial for maintaining the temporal and spatial coherence of bonded social groups. Using comparative data, we show that in primates the capacity to inhibit behaviour when making decisions correlates better with the demands of social contexts than the demands of foraging contexts. We argue that the capacity to inhibit prepotent action has been crucial for the evolution of bonded social systems in primates and some other mammals. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.26.354977v1?rss=1 Authors: Marinos, J., Ashbaugh, A. Abstract: Objective: The present study examined if the expectation for learning enhances reconsolidation of conditioned fear memories using the post-retrieval extinction paradigm in an undergraduate sample (n = 48). Methods: The study took place over three consecutive days. The expectation for learning was manipulated through oral instructions prior to memory reactivation. On day one, participants underwent differential fear conditioning to two spider images (CS+ and CS-). On day two, participants were assigned to either a reactivation with expectation for learning group, a reactivation with no expectation for learning group, or a no reactivation group. On day three, return of fear in response to the CS+ spider image was measured following reinstatement (i.e., four shocks). Fear potentiated startle (FPS) and skin conductance response (SCR) were taken as measures of fear. Results: The study found evidence that the expectation for learning may enhanced reconsolidation with FPS as a measure of fear as it was only the expectation for learning group in which FPS to the CS+ remained stable following reinstatement, however this effect was small and non-robust. In contrast, no evidence of reconsolidation was observed for SCR, as all participants exhibited a return of fear following reinstatement. Implications: These findings suggest that a verbal manipulation of the expectation for learning may not be salient enough to induce reconsolidation as measured by SCR but may be sufficient as measured by FPS. Additionally, given in the inconsistent findings between SCR and FPS, the studys results bring into question whether the post-retrieval extinction paradigm is appropriate to investigate reconsolidation using both physiological measures concurrently. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.23.352369v1?rss=1 Authors: Hahn, L. G., Oswald, P., Caspers, B. A. Abstract: Predation is one of the strongest selection pressures, forcing prey organisms to detect predators and to display various antipredator behaviours, such as refuge-use or decreased activity. To recognise predators, chemosensory cues play a pivotal role, particularly in aquatic ecosystems. However, it is less known whether the ability to use these cues to respond with adequate antipredator behaviour varies between individuals occupying different habitats that are dissimilar in predation risk. Using field experiments, we examined antipredator behaviour of larval fire salamanders (Salamandra salamandra) from two different habitats, ponds and streams. Among other differences, ponds and streams are inhabited by habitat-specific predators, such as alpine newts (Ichthyosaura alpestris) occurring in ponds. We exposed larvae from both habitats to either chemical cues from alpine newts or a blank control (tap water) and investigated potential differences in their behavioural responses in two experiments. Pond larvae, but not stream larvae, became significantly less active when faced with chemical cues from newts compared to those faced with a control stimulus. Moreover, larvae from both habitats tested in water containing chemical cues spent significantly less time outside a shelter than those in control water. Our results demonstrate that larval fire salamanders recognise predatory newts through kairomones and alter their behaviour accordingly. However, experience with predatory newts may not be necessary to differentiate kairomones from control water, but may be beneficial for larvae to further develop their antipredator behaviour, thus representing conformance to a niche. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.22.350926v1?rss=1 Authors: Dasgupta, D., Banerjee, A., Karar, R., Banerjee, D., Mitra, S., Sardar, P., Karmakar, S., Bhattacharya, A., Ghosh, S., Bhattacharjee, P., Paul, M. Abstract: Urbanization affects concurrent human-animal movements as a result of altered resource availability and land use pattern, which leads to considerable ecological consequences. While some animals find themselves adrift, homeless with the uncertainty of resources resulting from the urban encroachment, few of them manage to survive by altering their natural behavioural patterns, and co-exist with humans. Folivorous colobines, such as grey langur, whose feeding repertoire largely consists of plant parts, tend to be more attuned to the urban high-calorie food sources to attain maximum fitness benefits within the concrete jungle having an insignificant green cover. However, such a mismatch between their generalized feeding behaviour and specialized gut physiology reminds us of the Liem's paradox and demands considerable scientific attention which could tell us the story behind colobines' successful co-existence within human settlements. Besides understanding their population dynamics, the effective management of these urbanized, free-ranging, non-human primate populations also depends on their altered feeding preferences, altogether which could lead us to the development of an ecologically sound urban ecosystem. Here, we have used a field-based experimental set up which allows langurs to choose between natural and urban food options, being independent of any inter-specific conflicts over resources due to food scarcity. The multinomial logit model reveals the choice-based decision making of these free-ranging grey langurs in an urban settlement of West Bengal, India, where they have not only learned to approach the human-provisioned urban food items but also shown a keen interest in it. While urbanization imposes tremendous survival challenges to these animals, it also opens up for various alternative options for human-animal co-existence which is reflected in this study, and could guide us for the establishment of a sustainable urban ecosystem in the future. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.20.347872v1?rss=1 Authors: Kitano, K., Yamagishi, A., Horie, K., Nishimori, K., Sato, N. Abstract: Accumulated evidence across animals suggests that helping behavior is triggered by empathy. We examined whether prairie voles, one of the more highly social animals, help conspecifics who are soaked in water by opening a door to a safe area. Door-opening latency decreased as task sessions progressed, suggesting that prairie voles learn helping behavior. In addition, when the conspecific was not soaked in water, the latency of the door-opening did not decrease, suggesting that the distress of the conspecific is necessary for the learning of the door-opening. Thus, the door-opening behavior in prairie voles can be considered a helping behavior that is motivated by empathy for the distress of conspecifics. We also examined the helping behavior in prairie voles in which oxytocin receptors were genetically knocked out. Oxytocin receptor knockout voles demonstrated impaired learning of the door-opening. This suggests that oxytocin is important for the emergence of helping behavior. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.19.345231v1?rss=1 Authors: Lundblad, J., Rashid, M., Rhodin, M., Haubro Andersen, P. Abstract: Horses have the ability to generate a remarkable repertoire of facial expressions, some which have been linked to certain emotional states, for example pain. Studies suggest that facial expressions may be a more honest expression of emotional state in horses than behavioral or physiological parameters. This study sought to describe the facial expressions during stress of healthy horses free of pain, using a standardized method of recording facial expressions in video. Stress was induced in 28 horses by subjecting them to road transport and 10 of these horses were also subjected to social isolation. The horses served as their own control. A body-mounted, remote controlled heart rate monitor provided continuous heart rate measurements during the interventions. The horses facial expressions were video-recorded during the interventions. Frequency and duration of each facial expression were then determined, according to the Equine Facial Action Coding System. Heart rate increased during the stressful interventions (p=0.01), confirming that the interventions were stressful. Using both the human investigation- and the co-occurrence methods, the following facial traits could be observed during stress: eye white increase (p

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.15.341545v1?rss=1 Authors: Rossborough, J., Salles, A., Stidsholt, L., Madsen, P., Moss, C., Hoffman, L. Abstract: Sensory processing of environmental stimuli during locomotion is critical for the successful execution of goal-directed behaviors and navigating around obstacles. The outcome of these sensorimotor processes can be challenged by head movements that perturb the sensory coordinate frames directing behaviors. In the case of visually-guided behaviors, visual gaze stabilization results from the integrated activity of the vestibuloocular reflex and motor efference copy originating within circuits driving locomotor behavior. A recent videographic study showed that echolocating bats exhibit inflight head stabilization during a target identification and landing task, though compensatory timing of the bats' sonar signals was not reported. In the present investigation we tested hypotheses that head stabilization is more broadly implemented during epochs of exploratory flight, and is temporally associated with emitted sonar signals, which would optimize acoustic gaze. This was achieved by measuring head and body kinematics with motion sensors secured to the head and body of free-flying Egyptian fruit bats. These devices were integrated with ultrasonic microphones to record the bat's sonar emissions and elucidate their temporal association with periods of head stabilization. Head accelerations in the Earth-vertical axis were asymmetric with respect to wing downbeat and upbeat relative to body accelerations. This indicated that inflight head and body accelerations were uncoupled, outcomes consistent with the implementation of head movements that limit vertical acceleration during wing downbeat. Furthermore, sonar emissions during stable flight occurred most often during wing downbeat and head stabilization, supporting the conclusion that head stabilization behavior optimized sonar gaze and environmental interrogation via echolocation. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.14.338996v1?rss=1 Authors: Walter, T., Couzin, I. D. Abstract: Automated visual tracking of animals is rapidly becoming an indispensable tool for the study of behavior. It offers a quantitative methodology by which organisms' sensing and decision-making can be studied in a wide range of ecological contexts. Despite this, existing solutions tend to be challenging to deploy in practice, especially when considering long and/or high-resolution video streams. Here, we present TRex, a fast and easy-to-use solution for tracking a large number of individuals simultaneously with real-time (60Hz) tracking performance for up to approximately 256 individuals and estimates 2D body postures and visual fields, both in open- and closed-loop contexts. Additionally, TRex offers highly-accurate, deep-learning-based visual identification of up to approximately 100 unmarked individuals, where it is between 2.5-46.7 times faster, and requires 2-10 times less memory, than comparable software (with relative performance increasing for more organisms and longer videos) and provides interactive visualization and data-exploration within an intuitive, platform-independent graphical user interface. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.14.337220v1?rss=1 Authors: Aoto, S., Hangai, M., Ueno-Yokohata, H., Ueda, A., Igarashi, M., Ito, Y., Tsukamoto, M., Jinno, T., Sakamoto, M., Okazaki, Y., Hasegawa, F., Ogata-Kawata, H., Namura, S., Kojima, K., Kikuya, M., Matsubara, K., Taniguchi, K., Okamura, K. Abstract: Deep learning has rapidly been filtrating many aspects of human lives. In particular, image recognition by convolutional neural networks has inspired numerous studies in this area. Hardware and software technologies as well as large quantities of data have contributed to the drastic development of the field. However, the application of deep learning is often hindered by the need for big data and the laborious manual annotation thereof. To experience deep learning using the data compiled by us, we collected 2429 constrained headshot images of 277 volunteers. The collection of face photographs is challenging in terms of protecting personal information; we established an online procedure in which both the informed consent and image data could be obtained. We did not collect personal information, but issued agreement numbers to deal with withdrawal requests. Gender and smile labels were manually and subjectively annotated only from the appearances, and final labels were determined by majority among our team members. Rotated, trimmed, resolution-reduced, decolorized, and matrix-formed data were allowed to be publicly released. Moreover, simplified feature vectors for data sciences were released. We performed gender recognition by building convolutional neural networks based on the Inception V3 model with pre-trained ImageNet data to demonstrate the usefulness of our dataset. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.12.336586v1?rss=1 Authors: Rahn, R. M., Weichselbaum, C. T., Gutmann, D. H., Dougherty, J. D., Maloney, S. E. Abstract: Motor deficits such as abnormal gait are an underappreciated yet characteristic phenotype of many neurodevelopmental disorders (NDDs), including Williams Syndrome (WS) and Neurofibromatosis Type 1 (NF1). Compared to cognitive phenotypes, gait phenotypes are readily and comparably assessed in both humans and model organisms, and are controlled by well-defined CNS circuits. Discovery of a common gait phenotype between NDDs might suggest shared cellular and molecular deficits and highlight simple outcome variables to potentially quantify longitudinal treatment efficacy in NDDs. We therefore characterized gait using the DigiGait assay in two different murine NDD models: the complete deletion (CD) mouse, which models hemizygous loss of the complete WS locus, and the Nf1+/R681X mouse, which models a NF1 patient-derived heterozygous germline NF1 mutation. Longitudinal data were collected across five developmental time points (postnatal days 21-30) and one early adulthood time point. Compared to wild type littermate controls, both models displayed markedly similar spatial, temporal, and postural gait abnormalities during development. Developing CD mice also displayed significant decreases in variability metrics. Multiple gait abnormalities observed across development in the Nf1+/R681X mice persisted into early adulthood, including increased stride length and decreased stride frequency, while developmental abnormalities in the CD model largely resolved by adulthood. These findings suggest that the subcomponents of gait affected in NDDs show overlap between disorders as well as some disorder-specific features, which may change over the course of development. Our incorporation of spatial, temporal, and postural gait measures also provides a template for gait characterization in other NDD models, and a platform to examining circuits or longitudinal therapeutics. Copy rights belong to original authors. Visit the link for more info

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.10.12.336024v1?rss=1 Authors: GomezdelaTorre Clavel, M. G., Youngblood, M., Lahti, D. Abstract: Domestication is the process by which species adapt to, and are artificially selected for, human-made environments. Few studies have explored how the process of domestication has affected the connection between behavioral traits and cognitive abilities in animals. This study investigated the relationship between personality and cognitive traits in domestic rabbits (Oryctolagus cuniculus). Fifteen individuals kept in a rabbit rescue facility were tested over a period of two months. We measured the linkage between behavioral traits (response to a novel object and exploration time) and cognitive performance. Our results suggest that there is no relationship between personality traits and problem solving abilities in domestic rabbits. In addition, our results suggest that exploration time is significantly repeatable at the individual level while latency to approach a novel object is not. Thus further research is needed to explore the relationship between cognitive and personality traits in domestic rabbits. Copy rights belong to original authors. Visit the link for more info