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COORDINATED TURNING BEHAVIOUR OF LOITERING HONEYBEES (APIS MELLIFERA)

Turning during flight is a complex behaviour that requires coordination to ensure that the resulting centrifugal force is never large enough to disrupt the intended turning trajectory. The centrifugal force during a turn increases with the curvature (sharpness) of the turn, as well as the speed of flight. Consequently, sharp turns would require lower flight speeds, in order to limit the centrifugal force to a manageable level and prevent unwanted sideslips. We have video-filmed honeybees flying near a hive entrance when the entrance is temporarily blocked. A 3D reconstruction and analysis of the flight trajectories executed during this loitering behaviour reveals that sharper turns are indeed executed at lower speeds. During a turn, the flight speed is matched to the curvature, moment to moment, in such a way as to maintain the centrifugal force at an approximately constant, low level of about 30% of the body weight, irrespective of the speed or the curvature of the turn. This ensures that turns are well coordinated, with few or no sideslips - as is evident from analysis of other properties of the flight trajectories.

animal behavior and cognition

Pupation site preference selection in Drosophila jambulina

Larvae of Drosophila jambulina belonging to montium subgroup were tested for pupation site preference in relation to temperature. At higher temperature (30 {degrees}C), larvae preferred to pupate on food whereas at lower temperature (21 {degrees}C) pupation occurred on the cotton. Genetic basis of larval pupation behavior was studied by conducting reciprocal crosses for 30 generations on food-selected and on cotton-selected larvae. Results from genetic analysis between food-selected and cotton-selected strains suggested a single gene responsible for the pupation site preference, with F1 progeny pupated on cotton and F2 (F1x;F1) larvae pupated on both food as well on cotton. Although we found no change in morphological traits in food vs. cotton selected population, significantly different growth rate (body weight) between the two strains was observed. These results suggest that pupation site preferences can affect life-history traits in D. jambulina.

animal behavior and cognition

Taste Receptor Cells in Mice Express Receptors for the Hormone Adiponectin

The metabolic hormone adiponectin is secreted into the circulation by adipocytes, and mediates key biological functions including insulin sensitivity, adipocyte development, and fatty acid oxidation. Adiponectin is also abundant in saliva, where its functions are poorly understood. Here we report that murine taste receptor cells express adiponectin receptors, and may be a target for salivary adiponectin. Analysis of a transcriptome dataset obtained by RNA-seq analysis of purified circumvallate taste buds, revealed high expression levels for three adiponectin receptor types. Immunohistochemical studies showed that two of these receptors, AdipoR1 and T-cadherin, are localized to subsets of taste receptor cells. Immunofluorescence for T-cadherin was primarily co-localized with the Type 2 taste receptor cell marker phospholipase {beta}2, suggesting that adiponectin signaling could impact sweet, bitter, or umami taste signaling. However, adiponectin null mice showed no differences in taste responsiveness compared to wildtype controls in brief-access taste testing. AAV-mediated overexpression of adiponectin in the salivary glands of adiponectin null mice did result in a small but significant increase in behavioral taste responsiveness to the fat emulsion Intralipid. Together, these results suggest that salivary adiponectin can effect taste receptor cell function, though its impact on taste responsiveness and peripheral taste coding remains unclear.

animal behavior and cognition

Innate visual preferences and behavioral flexibility in Drosophila

Visual decision-making in animals is influenced by innate preferences as well as experience. Interaction between hard-wired responses and changing motivational states determines whether a visual stimulus is attractive, aversive, or neutral. It is however difficult to separate the relative contribution of nature versus nurture in experimental paradigms, especially for more complex visual parameters such as the shape of objects. We used a closed-loop virtual reality paradigm for walking Drosophila flies to uncover innate visual preferences for the shape and size of objects, in a recursive choice scenario allowing the flies to reveal their visual preferences over time. We found that Drosophila flies display a robust attraction / repulsion profile for a range of objects sizes in this paradigm, and that this visual preference profile remains evident under a variety of conditions and persists into old age. We also demonstrate a level of flexibility in this behavior: innate repulsion to certain objects could be transiently overridden if these were novel, although this effect was only evident in younger flies. Finally, we show that a reward circuit in the fly brain, Drosophila neuropeptide F (dNPF), can be recruited to guide visual decision-making. Optogenetic activation of dNPF-expressing neurons converted a visually repulsive object into a more attractive object. This suggests that dNPF activity in the Drosophila brain guides ongoing visual choices, to override innate preferences and thereby provide a necessary level of behavioral flexibility in visual decision-making.

animal behavior and cognition

Robust Mouse Tracking in Complex Environments using Neural Networks

The ability to track animals accurately is critical for behavioral experiments. For video-based assays, this is often accomplished by manipulating environmental conditions to increase contrast between the animal and the background, in order to achieve proper foreground/background detection (segmentation). However, as behavioral paradigms become more sophisticated with ethologically relevant environments, the approach of modifying environmental conditions offers diminishing returns, particularly for scalable experiments. Currently, there is a need for methods to monitor behaviors over long periods of time, under dynamic environmental conditions, and in animals that are genetically and behaviorally heterogeneous. To address this need, we developed a state-of-the-art neural network-based tracker for mice, using modern machine vision techniques. We test three different neural network architectures to determine their performance on genetically diverse mice under varying environmental conditions. We find that an encoder-decoder segmentation neural network achieves high accuracy and speed with minimal training data. Furthermore, we provide a labeling interface, labeled training data, tuned hyperparameters, and a pre-trained network for the mouse behavior and neuroscience communities. This general-purpose neural network tracker can be easily extended to other experimental paradigms and even to other animals, through transfer learning, thus providing a robust, generalizable solution for biobehavioral research.

animal behavior and cognition

MHC GENETIC VARIATION INFLUENCES BOTH OLFACTORY SIGNALS AND SCENT DISCRIMINATION IN RING-TAILED LEMURS

Diversity at the Major Histocompatibility Complex (MHC) is critical to health and fitness, such that MHC genotype may predict an individuals quality or compatibility as a competitor, ally, or mate. Moreover, because MHC products can influence the components of bodily secretions, an individuals body odor may signal its MHC and influence partner identification or mate choice. To investigate MHC-based signaling and recipient sensitivity, we test for odor-gene covariance and behavioral discrimination of MHC diversity and pairwise dissimilarity, under the good genes and good fit paradigms, in a strepsirrhine primate, the ring-tailed lemur (Lemur catta). First, we coupled genotyping with gas chromatography-mass spectrometry to investigate if diversity of the MHC-DRB gene is signaled by the chemical diversity of lemur genital scent gland secretions. We also assessed if the chemical similarity between individuals correlated with their MHC similarity. Next, we assessed if lemurs discriminated this chemically encoded, genetic information in opposite-sex conspecifics. We found that both sexes signaled overall MHC diversity and pairwise MHC similarity via genital secretions, but in a sex- and season-dependent manner. Additionally, both sexes discriminated absolute and relative MHC-DRB diversity in the genital odors of opposite-sex conspecifics, supporting previous findings that lemur genital odors function as advertisement of genetic quality. In this species, genital odors provide honest information about an individuals absolute and relative MHC quality. Complementing evidence in humans and Old World monkeys, our results suggest that reliance on scent signals to communicate MHC quality may be important across the primate lineage.

animal behavior and cognition

Movement and conformity interact to establish local behavioural traditions in animal populations

The social transmission of information is critical to the emergence of animal culture. Two processes are predicted to play key roles in how socially-transmitted information spreads in animal populations: the movement of individuals across the landscape and conformist social learning. We develop a model that, for the first time, explicitly integrates these processes to investigate their impacts on the spread of behavioural preferences. Our results reveal a strong interplay between movement and conformity for determining whether local traditions establish across a landscape or whether a single preference dominates the whole population. The model is able to replicate a real-world cultural diffusion experiment in great tits Parus major, but also allows for a range of predictions for the emergence of animal culture under various initial conditions, habitat structure and strength of conformist bias to be made. Integrating social behaviour with ecological variation will be important for understanding the stability and diversity of culture in animals.

animal behavior and cognition

In a temporally segmented experience hippocampal neurons represent temporally drifting context but not discrete segments.

There is widespread agreement that episodic memory is organized into a timeline of past experiences. Recent work suggests that the hippocampus may parse the flow of experience into discrete episodes separated by event boundaries. A complementary body of work suggests that context changes gradually as experience unfolds. We recorded from hippocampal neurons as male long evans rats performed 6 blocks of an object discrimination task in sets of 15 trials. Each block was separated by removal from the testing chamber for a delay to enable segmentation. The reward contingency reversed from one block to the next to incentivize segmentation. We expected animals to hold two distinct, recurring representations of context to match the two distinct rule contingencies. Instead, we found that overtrained rats began each block neither above nor below chance but by guessing randomly. While many units had clear firing fields selective to the conjunction of objects in places, a significant population also reflected a continuously drifting code both within block and across blocks. Despite clear boundaries between blocks, we saw no neural evidence for event segmentation in this experiment. Rather, the hippocampal ensemble drifted continuously across time. This continuous drift in the neural representation was consistent with the lack of segmentation observed in behavior.\n\nSignificance StatementThe neuroscience literature yet to reach consensus as to how hippocampal firing fields support the organizing of events across time in episodic memory. Initial reports of hippocampal activity focused on discrete episodes within which representations were stable, and across which representations remapped. However, it remains unclear whether this segmentation of representations is merely an artifact of cue responsivity. More recently, research has shown that a proportion of the population codes for temporal aspects of context by exhibiting varying degrees of drift in their firing fields. Drift is hypothesized to represent a continually evolving temporal context, however it is unclear whether this drift is continuous or is also a mere artifact of changing experiences. We recorded from the dorsal hippocampus of rats performing an object discrimination task that involved contexts that were segmented in time. Overtrained rats were unable to anticipate the identity of the upcoming context, but may have used context boundaries to their advantage. Event segmentation theory predicts that hippocampal ensembles would alternate between behaviorally-relevant segments. Contrary to these predictions, animals showed weak evidence of context segmentation, even across blocks with different reward contingencies. Hippocampal ensembles showed neither evidence of alternating between stable contexts nor sensitivity to context boundaries, but did show robust temporal drift.

animal behavior and cognition

Contextual influence on confidence judgments in human reinforcement learning.

The ability to correctly estimate the probability of ones choices being correct is fundamental to optimally re-evaluate previous choices or to arbitrate between different decision strategies. Experimental evidence nonetheless suggests that this metacognitive process -referred to as a confidence judgment-is susceptible to numerous biases. We investigate the effect of outcome valence (gains or losses) on confidence while participants learned stimulus-outcome associations by trial-and-error. In two experiments, we demonstrate that participants are more confident in their choices when learning to seek gains compared to avoiding losses. Importantly, these differences in confidence were observed despite objectively equal choice difficulty and similar observed performance between those two contexts. Using computational modelling, we show that this bias is driven by the context-value, a dynamically updated estimate of the average expected-value of choice options that has previously been demonstrated to be necessary to explain equal performance in the gain and loss domain. The biasing effect of context-value on confidence, also recently observed in the context of incentivized perceptual decision-making, is therefore domain-general, with likely important functional consequences.

animal behavior and cognition

3D Reconstruction of Bird Flight Using a Single Video Camera

Video cameras are finding increasing use in the study and analysis of bird flight over short ranges. However, reconstruction of flight trajectories in three dimensions typically requires the use of multiple cameras and elaborate calibration procedures. We present an alternative approach that uses a single video camera and a simple calibration procedure for the reconstruction of such trajectories. The technique combines prior knowledge of the wingspan of the bird with a camera calibration procedure that needs to be used only once in the lifetime of the system. The system delivers the exact 3D coordinates of the position of the bird at the time of every full wing extension and uses interpolated height estimates to compute the 3D positions of the bird in the video frames between successive wing extensions. The system is inexpensive, compact and portable, and can be easily deployed in the laboratory as well as the field.

animal behavior and cognition

Assessment of self stigma and medication adherence among patients with mental illness who had been treated in Jimma Hospital, Western Ethiopia,2017: community based cross sectional study

Backgroundself Stigma associated with psychiatric disorders and its treatment toward patients with mental illness is the main challengers for early and successful treatment outcome.\n\nObjectiveTo assess the association between self stigma and level of medication adherence among patients with mental illness who have been treated at psychiatric clinic, JUSH, South West Ethiopia, 2017.\n\nMethodsThis study is a community based cross sectional study design using a case tracing method to identify patients in the community. To get the study subject, tracing method was carried to get the patients who had history of treatment at psychiatric clinic, Jimma University Teaching Hospital. Interview based Questionnaire was used to get information from the participants. The relationship was checked by doing both bivariate and multi variables linear regression.\n\nResultOf the total respondents, males were185 (61.7%), females 115 (38.3%), and the mean age of the respondents was 34.99 (SD=11.51) years. From the total (n=300) respondents, more than half of them, 182 (60.7%) were adherent to their psychotropic medication. Among adherent respondents, of all types of stigma, minimal stigma was 63.2% whereas moderate to high stigma was 22.4%.\n\nConclusionIt was identified that there was high self stigma related to medication non adherent among patients with mental illness. Therefore, mental health professionals and the health care policy shall work to increase the level of psychotropic medication adherence so as to decrease self stigma associated with mental illness.

animal behavior and cognition

Brain regions modulated during covert visual attention in the macaque

Neurophysiology studies of covert visual attention in monkeys have emphasized the modulation of sensory neural responses in the visual cortex. At the same time, electrophysiological correlates of attention have been reported in other cortical and subcortical structures, and recent fMRI studies have identified regions across the brain modulated by attention. Here we used fMRI in two monkeys performing covert attention tasks to reproduce and extend these findings in order to help establish a more complete list of brain structures involved in the control of attention. As expected from previous studies, we found attention-related modulation in frontal, parietal and visual cortical areas as well as the superior colliculus and pulvinar. We also found significant attention-related modulation in cortical regions not traditionally linked to attention - mid-STS areas (anterior FST and parts of IPa, PGa, TPO), as well as the caudate nucleus. A control experiment using a second-order orientation stimulus showed that the observed modulation in a subset of these mid-STS areas did not depend on visual motion. These results identify the mid-STS areas (anterior FST and parts of IPa, PGa, TPO) and caudate nucleus as potentially important brain regions in the control of covert visual attention in monkeys.

animal behavior and cognition

Adaptive switch to sexually dimorphic movements by partner-seeking termites

When searching for targets whose location is not known, animals should benefit by adopting movement patterns that promote random encounters. During mate search, theory predicts that the optimal search pattern depends on the expected distance to potential partners. A key question is whether actual males and females update their mate search patterns to increase encounter probability when conditions change. Here we show that two termite species, Reticulitermes speratus and Coptoterines formosanus, adaptively alternate between sexually monomorphic and dimorphic movements during mate search. After leaving their nests in a synchronized manner, termites begin to search for a mate. The resulting pairs perform tandem runs toward potential nest sites. We found that both sexes moved faster and in straight lines before finding partners, which is known to improve encounter rates when targets have completely unpredictable positions. In stark contrast, when pairs were accidentally separated during tandem running, they showed distinct sexually dimorphic movements, where females paused for long periods while males paused only briefly and moved actively. Data-based simulations demonstrated that such sexually dimorphic movements are advantageous when a mate is located nearby but its exact location is unknown. These results emphasize the importance of biological details to evaluate the efficiency of random search in animals. By extending the concept of mutual search beyond the context of mating, the dimorphic movements between partners represent a remarkable convergence between termites and other animals including humans.\n\nSignificance StatementHow should females and males move to search for partners whose exact location is unknown? Theory predicts that the answer depends on what they know about where targets can be found, indicating that the question doesnt make sense until the searching context is clarified. We demonstrated that termites adaptively switch their search modes depending on the potential distance to their partners. When the location of potential mates was completely unpredictable, both sexes moved in straight lines to explore widely. In contrast, when the stray partner was at least nearby, males moved while females paused. Simulations confirmed that these movements increase the rate of successful encounters. The context-dependent switch of search modes is a key to enhance random encounters in animals.

animal behavior and cognition

Multiple optic gland signaling pathways implicated in octopus maternal behaviors and death

0. Summary statementOctopus optic glands employ a multiplex progression of signaling molecules to regulate maternal behaviors.\n\n1. AbstractPost-reproductive life in the female octopus is characterized by an extreme pattern of maternal care: the mother cares for her clutch of eggs without feeding until her death. These maternal behaviors are completely eradicated if the optic glands, the octopus analog of the vertebrate pituitary gland, are removed from brooding females. Despite the optic glands importance in regulating maternal behavior, the molecular features underlying optic gland function are unknown. Here, we identify major signaling systems of the Octopus bimaculoides optic gland. Through behavioral analyses and transcriptome sequencing, we report that the optic gland undergoes remarkable molecular changes that coincide with transitions between behavioral stages. These include the dramatic up- and down-regulation of catecholamine, steroid, insulin, and feeding peptide pathways. Transcriptome analyses in other tissues demonstrate that these molecular changes are not generalized markers of aging and senescence, but instead, specific features of the optic glands. Our results provide strong evidence for the functional conservation of signaling molecules across evolutionarily distant species. For example, elevated levels of insulin growth factor binding proteins are associated with cachexia-like tissue wasting in flies, humans, and, reported here, octopuses. Our study expands the classic optic gland-pituitary gland analogy and indicates that, rather than a single \"self-destruct\" hormone, the maternal optic glands employ multiple pathways as systemic hormonal signals of behavioral control.

animal behavior and cognition

A central component of the N1 event-related brain potential could index the early and automatic inhibition of the actions systematically activated by objects

Stimuli of the environment, like objects, systematically activate the actions they are associated to. These activations occur extremely fast. Nevertheless, behavioural data reveal that, in most cases, these activations are then automatically inhibited, around 100 ms after the occurrence of the stimulus. We thus tested whether this early inhibition could be indexed by a central component of the N1 event-related brain potential (ERP). To achieve that goal, we looked at whether this ERP component is greater in tasks that could increase the inhibition and in trials where reaction times happen to be long. The illumination of a real space bar of a keyboard out of the dark was used as a stimulus. To maximize the modulation of the inhibition, the task participants had to performed was manipulated across blocks. A look-only task and a count task were used to increase inhibition and an immediate press task was used to decrease it. ERPs of the two block-conditions where presses had to be prevented and where the largest central N1s were predicted were compared to those elicited in the press task, differentiating the ERPs to the third of the trials where presses were the slowest from the ERPs to the third of the trials with the fastest presses. Despite larger negativities due to motor potentials and despite greater attention likely in immediate press-trials, central N1s were found to be minimal for the fastest presses, intermediate for the slowest ones and maximal for the two no-press conditions. These results thus provide a strong support for the idea that the central N1 indexes an early and short lasting automatic inhibition of the actions systematically activated by objects. They also confirm that the strength of this automatic inhibition spontaneously fluctuates across trials and tasks. On the other hand, just before N1s, parietal P1s were found greater for fastest presses. They might thus index the initial activation of these actions. Finally, consistent with the idea that N300s index late inhibition processes, that occur preferentially when the task requires them, these ERPs were quasi absent for fast presses trials and much larger in the three other conditions.\n\nHighlightsEvent-related brain potentials (ERPs) elicited by a real object\n\nSmaller parietal P1s and greater central N1s for slowest than for fastest motor responses\n\nEven greater central N1s for tasks without such responses\n\nCentral N1s may index early inhibition of stimulus-activated actions\n\nN300s could index late inhibition of stimulus-activated actions

animal behavior and cognition

Measurement invariance explains the universal law of generalization for psychological perception

The universal law of generalization describes how animals discriminate between alternative sensory stimuli. On an appropriate perceptual scale, the probability that an organism perceives two stimuli as similar typically declines exponentially with the difference on the perceptual scale. Exceptions often follow a Gaussian probability pattern rather than an exponential pattern. Previous explanations have been based on underlying theoretical frameworks such as information theory, Kolmogorov complexity, or empirical multidimensional scaling. This article shows that the few inevitable invariances that must apply to any reasonable perceptual scale provide a sufficient explanation for the universal exponential law of generalization. In particular, reasonable measurement scales of perception must be invariant to shift by a constant value, which by itself leads to the exponential form. Similarly, reasonable measurement scales of perception must be invariant to multiplication, or stretch, by a constant value, which leads to the conservation of the slope of discrimination with perceptual difference. In some cases, an additional assumption about exchangeability or rotation of underlying perceptual dimensions leads to a Gaussian pattern of discrimination, which can be understood as a special case of the more general exponential form. The three measurement invariances of shift, stretch, and rotation provide a sufficient explanation for the universally observed patterns of perceptual generalization. All of the additional assumptions and language associated with information, complexity, and empirical scaling are superfluous with regard to the broad patterns of perception.

animal behavior and cognition

Blue-green opponency and trichromatic vision in the greenhouse whitefly (Trialeurodes vaporariorum)

Visual orientation in the greenhouse whitefly (Trialeurodes vaporariorum Westwood, Hemiptera: Aleyrodidae) is the result of wavelength-specific behaviours. Green-yellow elicits settling behaviour while ultraviolet (UV) radiation initiates migratory behaviour. Electroretinograms of the photoreceptors spectral efficiency showed peaks in the green and the UV range and whitefly vision was said to be dichromatic.\n\nIn order to study the visual behaviour of T. vaporariorum, nineteen narrow-bandwidth LEDs covering the UV-A and visible range were used in combination with light scattering acrylic glass screens in a small-scale choice arena under greenhouse conditions. Multiple-choice and dual-choice assays were performed, resulting in LED-based behavioural action spectra of settling (green) and migratory behaviour (UV). A potential inhibitory blue-green chromatic mechanism was studied by combining yellow with different blueish LEDs. Intensity dependencies were illustrated by changing LED intensities.\n\nRegarding the settling response, highest attraction was achieved by a green LED with a centroid wavelength of 550 nm, while a blue LED with 469 nm proved to be most inhibitory. Behaviour was distinctly intensity dependent. Migratory behaviour was elicited the most by the UV LED with the shortest available wavelength of 373 nm. The results clearly prove the presence of a green and a yet undescribed blue sensitive photoreceptor and a blue-green opponent mechanism. Furthermore, empirical colour choice models were built and receptor peaks were estimated around 510 - 520 nm (green), 480 - 490 nm (blue) and 340 - 370 nm (UV). Consequently, Trialeurodes vaporariorum possesses a trichromatic receptor setup.\n\nSummary statementLED based choice experiments and empirical colour choice models reveal a yet undescribed blue sensitive photoreceptor and an inhibitory interaction with a green sensitive receptor.

animal behavior and cognition

Boundary Strength Analysis: Combining colour pattern geometry and coloured patch visual properties for use in predicting behaviour and fitness

Colour patterns are used by many species to make decisions that ultimately affect their Darwinian fitness. Colour patterns consist of a mosaic of patches that differ in geometry and visual properties. Although traditionally pattern geometry and colour patch visual properties are analysed separately, these components are likely to work together as a functional unit. Despite this, the combined effect of patch visual properties, patch geometry, and the effects of the patch boundaries on animal visual systems, behaviour and fitness are relatively unexplored. Here we describe Boundary Strength Analysis (BSA), a novel way to combine the geometry of the edges (boundaries among the patch classes) with the receptor noise estimate ({Delta}S) of the intensity of the edges. The method is based upon known properties of vertebrate and invertebrate retinas. The mean and SD of{Delta} S (m{Delta}S, s{Delta}S) of a colour pattern can be obtained by weighting each edge class{Delta} S by its length, separately for chromatic and achromatic{Delta} S. This assumes those colour patterns, or parts of the patterns used in signalling, with larger m{Delta}S and s{Delta}S are more stimulating and hence more salient to the viewers. BSA can be used to examine both colour patterns and visual backgrounds. BSA was successful in assessing the estimated conspicuousness of colour pattern variants in two species, guppies (Poecilia reticulata) and Gouldian finches (Erythrura gouldiae), both polymorphic for patch colour, luminance and geometry. The pattern difference between chromatic and achromatic edges in both species reveals the possibility that chromatic and achromatic edges could function differently. BSA can be applied to any colour pattern used in intraspecific and interspecific behaviour. Seven predictions and four questions about colour patterns are presented.

animal behavior and cognition