SEARCH · Search bioRxiv

Results for “Animal Behavior and Cognition”

Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

bioRxiv2016

Naïve chicks prefer hollow objects

Biological predispositions influence approach and avoid responses since the beginning of life. Neonates of species that require parental care (e.g. human babies and chicks of the domestic fowl) are attracted by stimuli associated with animate social partners, such as face-like configurations, biological motion and self-propulsion. The property of being filled is used as a cue of animacy by 8-month-old infants but it is not known whether this reflects the effect of previous experience. We use chicks of the domestic fowl (Gallus gallus) to investigate whether the property of being filled vs. hollow elicits spontaneous or learned preferences. To this aim we tested preferences of naIve and imprinted chicks for hollow and closed cylinders. Contrary to our expectations, we documented an unlearned attraction for hollow stimuli. The preference for hollow stimuli decreased when chicks were imprinted on filled stimuli but did not increase when chicks were imprinted on hollow stimuli, suggesting that this feature is not crucial to categorize the familiarity of imprinting objects. When chicks were imprinted on occluded stimuli that could be either filled or hollow, the preference for hollow stimuli emerged again, showing that imprinting does not disrupt the spontaneous preference for hollow objects. Further experiments revealed that hollow objects were mainly attractive by means of depth cues such as darker innards, more than as places to hide or as objects with high contrast. Our findings point to predisposed preferences for hollow objects that might be unrelated to social behaviour.

Animal Behavior and Cognition↗

bioRxiv2016

Proportion of cocaine-coding neurons in the orbitofrontal cortex determines individual drug preferences

Cocaine addiction is a harmful preference for drug use over and at the expense of other nondrug-related activities. Here we identify in the orbitofrontal cortex (OFC) - a prefrontal region involved in choice and decision-making - a mechanism that explains individual preferences in rats between cocaine use and an alternative, nondrug action. We found that initiation of these actions is selectively encoded by two non-overlapping populations of OFC neurons, and that the relative size and differential pre-choice activity of the cocaine action-coding population determine an individual preference, a larger size and a higher pre-choice activity being associated with cocaine preference. A larger size is a structural feature that may confer to a population of OFC neurons a competitive advantage during choice in favor of the encoded action. Such structural encoding also explains two other major defining features of an individual drug preference, its stability over time and its resistance to change.

Animal Behavior and Cognition↗

bioRxiv2016

Serotonin-dependent kinetics of bursts of feeding underlie a graded response to food availability

Animals integrate physiological and environmental signals to modulate their food uptake. Failure to regulate feeding may have devastating results, including obesity and diabetes, underscoring the importance of understanding its underlying mechanisms. The nematode C. elegans, whose food uptake consists of pumping bacteria from the environment into the gut, provides excellent opportunities for discovering principles of conserved regulatory mechanisms. Here we show that worms implement a graded feeding response to the concentration of environmental bacteria by modulating a commitment to bursts of fast pumping. Using long-term, high-resolution, longitudinal recordings of feeding dynamics under defined conditions, we find that the frequency and duration of pumping bursts increase and the duration of long pauses diminishes in environments richer in bacteria. The bioamine serotonin, a known feeding regulator in metazoa, is required for food-dependent induction of bursts as well as for maintaining their high rate of pumping through two distinct mechanisms. Following this phenotype quantitatively we identify the essential serotonergic neurons and the differential roles of distinct families of serotonin receptors. We propose that regulation of bursts is a conserved mechanism of behavior and motor control.

Animal Behavior and Cognition↗

bioRxiv2016

A scalable method for automatically measuring pharyngeal pumping in C. elegans

We describe a scalable automated method for measuring the pharyngeal pumping of Caenorhabditis elegans in controlled environments. Our approach enables unbiased measurements for prolonged periods, a high throughput, and measurements in controlled yet dynamically changing feeding environments. The automated analysis compares well with scoring pumping by visual inspection, a common practice in the field. In addition, we observed overall low rates of pharyngeal pumping and long correlation times when food availability was oscillated.

Animal Behavior and Cognition↗

bioRxiv2016

Performance in a GO/NOGO perceptual task reflects a balance between impulsive and instrumental components of behaviour

In recent years, simple GO/NOGO behavioural tasks have become popular due to the relative ease with which they can be combined with technologies such as in vivo multiphoton imaging. To date, it has been assumed that behavioural performance can be captured by the average performance across a session, however this neglects the effect of motivation on behaviour within individual sessions. We investigated the effect of motivation on mice performing a GO/NOGO visual discrimination task. Performance within a session tended to follow a stereotypical trajectory on a Receiver Operating Characteristic (ROC) chart, beginning with an over-motivated state with many false positives, and transitioning through a more or less optimal regime to end with a low hit rate after satiation. Our observations are reproduced by a new model, the Motivated Actor-Critic, introduced here. Our results suggest that standard measures of discriminability, obtained by averaging across a session, may significantly underestimate behavioural performance.

Animal Behavior and Cognition↗

bioRxiv2016

Automatic classification of behavior in zebrafish larvae

Zebrafish larvae navigate the environment by discrete episode of propulsion called bouts. We introduce a novel method for automatically classifying tail bouts. A supervised soft-clustering algorithm to categorize tail bouts into 5 categories of movements: Scoot, Asymmetrical Scoot, Routine Turn, C Bend and Burst. Tail bouts were correctly classified with 82% chance while errors in the classification occurred mostly between similar categories. Although previous studies have performed categorization of behavior in free-swimming conditions, our method does not rely on the analysis of the larvas trajectory and is thus compatible with both free-swimming and functional imaging in head-fixed condition.

Animal Behavior and Cognition↗

bioRxiv2016

Predictability and hierarchy in Drosophila behavior

Even the simplest of animals exhibit behavioral sequences with complex temporal dynamics. Prominent amongst the proposed organizing principles for these dynamics has been the idea of a hierarchy, wherein the movements an animal makes can be understood as a set of nested sub-clusters. Although this type of organization holds potential advantages in terms of motion control and neural circuitry, measurements demonstrating this for an animals entire behavioral repertoire have been limited in scope and temporal complexity. Here, we use a recently developed unsupervised technique to discover and track the occurrence of all stereotyped behaviors performed by fruit flies moving in a shallow arena. Calculating the optimally predictive representation of the flys future behaviors, we show that fly behavior exhibits multiple time scales and is organized into a hierarchical structure that is indicative of its underlying behavioral programs and its changing internal states.

Animal Behavior and Cognition↗

bioRxiv2016

Deriving shape-based features for C. elegans locomotion using dimensionality reduction methods

High-throughput analysis of animal behavior has become a reality with the advance of recording technology, leading to large high-dimensional data sets. This dimensionality can sometimes be reduced while still retaining relevant information. In the case of the nematode worm Caenorhabditis elegans, more than 90% of the shape variance can be captured using just four principal components. However, it remains unclear if other methods can achieve a more compact representation or contribute further biological insight to worm locomotion. Here we take a data-driven approach to worm shape analysis using independent component analysis (ICA), non-negative matrix factorization (NMF), a cosine series, and jPCA and confirm that the dimensionality of worm shape space is close to four. Projecting worm shapes onto the bases derived using each method gives interpretable features ranging from head movements to tail oscillation. We use these as a comparison method to find differences between the wild type N2 worms and various mutants. The different bases provide complementary views of worm behavior and we expect that closer examination of the time series of projected amplitudes will lead to new results in the future.

Animal Behavior and Cognition↗

bioRxiv2016

Kin Recognition in a Clonal Fish, Poecilia formosa

Relatedness strongly influences social behaviors in a wide variety of species. For most species, the highest typical degree of relatedness is between full siblings with 50% shared genes. However, this is poorly understood in species with unusually high relatedness between individuals: clonal organisms. Although there has been some investigation into clonal invertebrates and yeast, nothing is known about kin selection in clonal vertebrates. We show that a clonal fish, the Amazon molly (Poecilia formosa), can distinguish between different clonal lineages, associating with genetically identical, sister clonals, and use multiple sensory modalities. Also, they scale their aggressive behaviors according to the relatedness to other females: they are more aggressive to non-related clones. Our results demonstrate that even in species with very small genetic differences between individuals, kin recognition can be adaptive. Their discriminatory abilities and regulation of costly behaviors provides a powerful example of natural selection in species with limited genetic diversity.

Animal Behavior and Cognition↗

bioRxiv2016

Composite Brownian Walks Best Describe Livestock Mobility Patterns across Species

In quantitative studies on animal movements and foraging, there has been ongoing debate over the relevance of Levy walk and related stochastic models to understanding mobility patterns of diverse organisms. In this study, we collected and analyzed a large number of GPS logs that tracked the movements of different livestock species in northwestern Kenya. Statistically principled analysis has only found limited evidence for the scale-free movement patterns of the Levy walk and its variants, even though most of the tracked movements clearly show super-diffusive behavior within the relevant temporal duration. Instead, the analysis has given strong support to composite exponential distributions (composite Brownian walks) as the best description of livestock movement trajectories in a wide array of parameter settings. Furthermore, this support has become overwhelming and near universal under an alternative criterion for model selection. These results illuminate the multi-scale and multi-modal nature of livestock spatial behavior. They also have broader theoretical and empirical implications for the related literature.

Animal Behavior and Cognition↗

bioRxiv2016

Ancient DNA reveals differences in behaviour and sociality between brown bears and extinct cave bears.

Ancient DNA studies have revolutionised the study of extinct species and populations, providing insights on phylogeny, phylogeography, admixture and demographic history. However, inferences on behaviour and sociality have been far less frequent. Here, we investigate the complete mitochondrial genomes of extinct Late Pleistocene cave bears and middle Holocene brown bears that each inhabited multiple geographically proximate caves in northern Spain. In cave bears, we find that, although most caves were occupied simultaneously, each cave almost exclusively contains a unique lineage of closely related haplotypes. This remarkable pattern suggests extreme fidelity to their birth site in cave bears, best described as homing behaviour, and that cave bears formed stable maternal social groups at least for hibernation. In contrast, brown bears do not show any strong association of mitochondrial lineage and cave, suggesting that these two closely related species differed in aspects of their behaviour and sociality. This difference is likely to have contributed to cave bear extinction, which occurred at a time in which competition for caves between bears and humans was likely intense and the ability to rapidly colonise new hibernation sites would have been crucial for the survival of a species so dependent on caves for hibernation as cave bears. Our study demonstrates the potential of ancient DNA to uncover patterns of behaviour and sociality in ancient species and populations, even those that went extinct many tens of thousands of years ago.

Animal Behavior and Cognition↗

bioRxiv2016

Female-female aggression in a sexual/unisexual species complex over resources

Kin selection theory predicts that closely related individuals should be more altruistic and less antagonistic towards one another. In addition, it would predict that the higher the relatedness value (R) between individuals, such as in clonal organisms, the more likely kin selection is to evolve. One benefit of kin selection is a reduction in aggression towards kininvarious social contexts, such as foraging. In the gynogenetic Amazon molly, Poecilia formosa, females have been shown to differentiate between clone types, preferring to associate with clonal sisters to non-sisters, and regulate their aggressive behaviors accordingly. We ask ifAmazon mollies in resource-limited environments: 1) still maintain the ability to regulate aggressive behaviors according to relatedness (heterospecific females, clonal sisters or non-sisters), and 2) how their aggressivebehaviors change relative to a females social partner? Using a repeated-measures design, we found that focal females regulated their aggressive behaviors depending on partner type (i.e., a heterospecific female, clonal sister, or non-sister). Heterospecific females and the non-sister clones spent more time behaving aggressively towards the focal females, and these females also received significantly more bites from heterospecific females. Interestingly, the clonal sisters, when compared to the other two female types, performed significantly more tail beats towards focal females.We are able to confirm that females do show more aggression towards heterospecific females and non-sister clones in a food-limited environment, andthat their aggression scales with relatedness (R).\n\nLay SummaryKin recognition allows individuals to adjust costly behaviors, such as aggression, according to the degree of genetic relatedness. We show that in a food-limited environment, a clonal species of fish, the Amazon molly, females regulate aggressive behaviors depending on how closely related they are to the recipient female, behaving more aggressively to both heterospecific females and non-sister clones. The ability to regulate costly behaviors under variable socialconditions is advantageous, especially when resources are limited.

Animal Behavior and Cognition↗

bioRxiv2016

On the optimal response vigor and choice under variable motivational drives

Within a rational framework, a decision-maker selects actions based on the reward-maximisation principle, i.e., acquiring the highest amount of reward with the lowest cost. Action selection can be divided into two dimensions: (i) selecting an action among several alternatives, and (ii) choosing the response vigor, i.e., how fast the selected action should be executed. Previous works have addressed the computational substrates of such a selection process under the assumption that outcome values are stationary and do not change during the course of a session. This assumption does not hold when the motivational drive of the decision-maker is variable, because it leads to changes in the values of the outcomes, e.g., satiety decreases the value of the outcome. Here, we utilize an optimal control framework and derive the optimal choice and response vigor under different experimental conditions. The results imply that, in contrast to previous suggestions, even under conditions that the values of the outcomes are changing during the session, the optimal response rate in an instrumental conditioning experiment is a constant response rate rather than decreasing. Furthermore, we prove that the uncertainty of the decision-maker about the duration of the session explains the commonly observed decrease in response rates within a session. We also show that when the environment consists of multiple outcomes, the model explains probability matching as well as maximisation choice strategies. These results, therefore, provide a quantitative analysis of optimal choice and response vigor under variable motivational drive, and provide predictions for future testing.

Animal Behavior and Cognition↗

bioRxiv2016

Operant Behavior in Model Systems

In contrast to the long-held assumption that the organization of behavior is best characterized as the perception of a sensory stimulus followed by appropriate response (i.e., \"sensorimotor hypothesis\"), recent converging evidence from multiple systems and fields of study instead suggests that both ancestral and extant general brain function is best described in operant terms. Rather than specifyng precise behaviors, sensory information - if at all present - interacts with ongoing neural activity to instruct the organism which type of spontaneous, exploratory behavior to generate. Evaluating the ensuing reafferent feedback modifies the nervous system such that ongoing neural activity patterns become biased towards activity that has generated increased appetitive and decreased aversive feedback in the past. The neurobiological mechanisms underlying both the exploratory, spontaneous behaviors as well as those underlying the modifications caused by the feedback are becoming increasingly understood, even on a molecular level. It is straightforward to hypothesize that the constant interaction between ongoing neural activity and the incoming sensory stream allows the organism to balance behavioral flexibility with efficiency to accomplish adaptive behavioral choice in an often unpredictably changing environment.

Animal Behavior and Cognition↗

bioRxiv2016

Calming Meditation Increases Altruism, Decreases Parochialism

It has been proposed that cultivating calm will increase altruism and decrease parochialism, where altruism is defined as self-sacrifice in support of others, regardless of group affiliation or identity, and parochialism is defined as prosocial self-sacrifice restricted to fellow members of a group. Such could be the case with a calming meditation practice. An alternate hypothesis, coming from the study of ritual, proposes that shared practices lead to bonding, increasing parochialism, but not altruism generally. These contradictory hypotheses of the potential effects of shared cultural practices of calming meditation were explored via a formal behavioral experiment using a simple treatment and control format with a short, facilitated breath awareness practice known to produce calm. Altruism and parochialism were measured through anonymous play in Public Goods games performed with both in-group and out-group individuals. The sum of contributions of the two plays gave a measure of altruism, while the difference between the two gave a measure of parochialism. The analysis of the results using Bayesian AICc model comparison methods supports the first hypothesis that calming practices reduces parochialism and increases altruism. The hypothesis of intentional shared practice as parochialism inducing was not supported by the results in this case of a shared calming practice.

Animal Behavior and Cognition↗

bioRxiv2016

The Cultural Evolution of Hard-to-fake Rituals

It has been proposed that costly rituals act as honest signals of commitment to group beliefs when such rituals appear dysphoric and unappealing (costly) to non-believers, but appealing to true believers (Irons, 2001). If only true believers are willing to endure ritual behaviors and true belief also entails belief in altruistic cooperation, associating with other ritual practitioners can help solve cooperation dilemmas in groups by sorting out potential free-riders. While this hypothesis is obviously true if such faking of ritual is strictly impossible, strict impossibility seems implausible. Faking is defined by Irons in this context to be to be performing the ritual without commitment to group beliefs. In this paper, I posit various ways that such faking might be difficult, instead of impossible, or different ways in which such ritual faking might be costly and then formally model the social learning and cultural evolution dynamics to see where it may still hold theoretically that such rituals help maintain altruism in group and under what conditions. Analytic solution for evolutionary equilibrium is derived for each model, verifying that under a wide range of conditions for some, but not all interpretations, such hard-to fake rituals can help groups solve cooperative dilemmas, including in some circumstances that might not be intuitively obvious, such as where such free-riding is not visible and free-riders successfully represent themselves as true believers to observers.\n\nIt is also the case that while there has been some progress in cleaning up the definitional confusions in the animal signaling literature around costly signaling, the literature on human rituals as costly signals has introduced novel uses of the term cost. Theories referring to completely different mechanisms or even definitions of cost are sometimes conflated. To contextualize the analysis of costly-to-fake rituals, this paper provides a review of the ideas proposed in the literature on costly human rituals and differentiates them from costly signaling as used in the animal behavior literature.

Animal Behavior and Cognition↗

bioRxiv2016

Consensus or deadlock? Consequences of simple behavioral rules for coordination in group decisions

Coordinated collective behaviors often emerge from simple rules governing the interactions of individuals in groups. We model mechanisms of coordination among ants during cooperative transport, a challenging task that requires a consensus on travel direction. Decisions required for cooperative transport differ from other, well-studied consensus decisions because groups often deadlock, with individuals trying to move in opposing directions, and cooperative transport groups are often relatively small. Small groups may be more affected by individual nonconformity. Using deterministic and stochastic models, we investigate behavioral factors that affect deadlock duration. Our goal is to determine whether groups following simple behavioral rules can reach a consensus using minimal information. We define and investigate multiple types of behavioral rules that govern individual behavior and also differ in the information available. We find that if individuals more readily give up when they are going against the majority, groups rapidly break deadlocks. This occurs through positive and negative feedbacks that are implemented in our model via a single mechanism. We also find that to quickly reach a consensus, groups must have either a shared bias, high sensitivity to group behavior, or finely tuned persistence. While inspired by ants, our results are generalizable to other collective decisions with deadlocks, and demonstrate that groups of behaviorally simple individuals with no memory and extremely limited information can break symmetry and reach a consensus in a decision between two equal options

Animal Behavior and Cognition↗

bioRxiv2016

Collective strategy for obstacle navigation during cooperative transport by ants

Group cohesion and consensus have primarily been studied in the context of discrete decisions, but some group tasks require making serial decisions that build on one another. We examine such collective problem solving by studying obstacle navigation during cooperative transport in ants. In cooperative transport, a group of ants works together to move a large object back to their nest. We blocked cooperative transport groups of Paratrechinal longicornis with obstacles of varying complexity, analyzing groups trajectories to infer what kind of strategy the ants employed. Simple strategies require little information, but more challenging, robust strategies succeed with a wider range of obstacles. We found that transport groups use a stochastic strategy that leads to efficient navigation around simple obstacles, and still succeeds at difficult ones. While groups navigating obstacles preferentially move directly toward the nest, they change their behavior over time; the longer the ants are obstructed, the more likely they are to move away from the nest. This increases the chance of finding a path around the obstacle. Groups rapidly changed directions and rarely stalled during navigation, indicating that these ants maintain consensus even when the nest direction is blocked. While some decisions were aided by the arrival of new ants, at many key points direction changes were initiated within the group, with no apparent external cause. This ant species is highly effective at navigating complex environments, and implements a flexible strategy that works quickly for simple obstacles and still succeeds with complex obstacles.

Animal Behavior and Cognition↗