Natural Behavior Of Animals Research Articles

Assessing Environmental Control Strategies in Cage-Free Egg Production Systems: Effect on Spatial Occupancy and Natural Behaviors.

Simple SummaryAn increment pattern in the worldwide egg production, as well as in the farm’s capacity in laying hen housing systems, have been observed for the last fifty years. Also, animal welfare has become a subject of interest due to consumer awareness. These issues have introduced new challenges to respond to international markets’ demands while ensuring animal welfare and environmental footprint. Cage-free systems have been alternative systems to ensure the well-being of laying hens. Likewise, environmental control strategies have been implemented to improve air quality since airborne contaminants’ concentration can be high inside these systems. Thus, the analysis of the effect of these strategies on natural behavior and flock distribution is essential to assess a comprehensive analysis. Four strategies and a control were tested in an experimental cage-free system. Spatial occupancy and animal behaviors were tracked using video recordings. Neither the four environmental strategies nor the control applied in this experiment affected the natural behaviors of hens. However, changes in flock distribution and stress patterns were identified in the treatment with a reduction in litter allowance. This study provides evidence that it is possible to implement strategies to improve air quality without disrupting natural animal behaviors in cage-free systems.Animal welfare concerns have been a challenging issue for producers and international marketing. In laying hen production, cage-free systems (CFS) have been identified as an alternative to ensure the laying hens’ well-being. Nevertheless, in CFS, important environmental issues have been reported, decreasing indoor air quality. Environmental control strategies (ECS) have been designed to enhance indoor air quality in CFSs. However, little information exists about the effect of these ECSs on natural animal behaviors. Four strategies and one control were tested in an experimental CFS, previously designed to track behavioral variables using video recordings over seven time-lapses of 1 hour per day. Spatial occupancy (SO) and laying hen behaviors (LHB) were registered. One statistical analysis was applied to evaluate the effect of ECS on SO and LHB using a multinomial response model. Results show lower chances to use litter area within the reduction of litter allowance treatment (T17) (p < 0.05). Neither the four ECSs nor the control implemented in this experiment affected the natural behaviors of the hens. However, stress patterns and high activity were reported in the T17 treatment. This study shows that it is possible to use these ECSs without disrupting laying hens’ natural behaviors.

Probabilistic causal inference for coordinated movement of pigeon flocks

One of the most striking examples of natural animal behavior is the highly ordered coordinated group movement, where inter-agent interaction is considered as a key factor tuning the coordination. To understand the interaction mechanism, a long-standing challenge is to reveal the causal relationship among the group individuals. In this study, we propose a causal inference method from the viewpoint of information theory. More precisely, we extend conditional information entropy of pairwise individuals with time delay, and subsequently induce causation entropy which quantifies the causal dependence of two individuals subject to a condition set consisting of other neighbors. Moreover, we analyze the high-resolution GPS data of three pigeon flocks to construct the interaction networks accordingly. We dynamically analyze the interaction characteristics and interestingly observe that the individuals closer to the mass center and the average velocity direction are more influential to the others. This study may shed some light onto the research of collective behaviors.

Improved 3D tracking and automated classification of rodents' behavioral activity using depth-sensing cameras.

Analysis of rodents' behavior/activity is of fundamental importance in many research fields. However, many behavioral experiments still rely on manual scoring, with obvious problems in reproducibility. Despite important advances in video-analysis systems and computational ethology, automated behavior quantification is still a challenge. The need for large training datasets, background stability requirements, and reduction to two-dimensional analysis (impairing full posture characterization), limit their use. Here we present a novel integrated solution for behavioral analysis of individual rats, combining video segmentation, tracking of body parts, and automated classification of behaviors, using machine learning and computer vision methods. Low-cost depth cameras (RGB-D) are used to enable three-dimensional tracking and classification in dark conditions and absence of color contrast. Our solution automatically tracks five anatomical landmarks in dynamic environments and recognizes seven distinct behaviors, within the accuracy range of human annotations. The developed free software was validated in experiments where behavioral differences between Wistar Kyoto and Wistar rats were automatically quantified. The results reveal the capability for effective automated phenotyping. An extended annotated RGB-D dataset is also made publicly available. The proposed solution is an easy-to-use tool, with low-cost setup and powerful 3D segmentation methods (in static/dynamic environments). The ability to work in dark conditions means that natural animal behavior is not affected by recording lights. Furthermore, automated classification is possible with only ~30 minutes of annotated videos. By creating conditions for high-throughput analysis and reproducible quantitative measurements of animal behavior experiments, we believe this contribution can greatly improve behavioral analysis research.

Editorial

Editorial

Sir Patrick Bateson FRS. 31 March 1938—1 August 2017

Patrick Bateson made outstanding contributions to the study of animal behaviour over a 50-year period, a field in which he was regarded as a world leader. His research involved analyses of the development, causal mechanisms, function and evolution of behaviour, and combined work in the experimental laboratory with observations of the natural behaviour of animals and theoretical analyses. With particular expertise on behavioural development, Bateson made seminal contributions to several topics, including filial imprinting, mate choice, developmental plasticity, the roles of behaviour and development in evolution, animal welfare and animal play. His research on imprinting in birds pioneered new methods, set new standards for behavioural research and shed new light on the interplay of internal and external factors during behavioural development. Recognizing that a complete understanding of behaviour requires investigation at a number of levels, Bateson's interactionist perspective led him to be highly critical of reductionism and of simple-minded use of terms such as ‘instinct’ and ‘innate’. Bateson published several influential books and well over 300 scientific articles, including a substantial number in flagship journals such as Nature and Science . His contribution to science was recognized with many honours, including a knighthood, the Frink Medal of the Zoological Society of London and the Distinguished Animal Behaviorist Career Award of the Animal Behavior Society. Bateson was also provost of Kings College Cambridge, president of the Zoological Society of London and biological secretary and vice-president of the Royal Society. A leading public intellectual in the early part of the twenty-first century, Bateson brought leadership and balanced judgement to many difficult issues, including the use of animals in medical research, dog breeding and hunting.

Comparison of Nest Defense Behaviors of Goshawks (Accipiter gentilis) from Finland and Montana.

Simple SummaryUnderstanding the degree to which human interaction may alter natural animal behavior has become increasingly important in developing effective conservation strategies. We examined two populations of northern goshawks (Accipiter gentilis) in Montana and Finland. Goshawks in Finland were not protected until the late 1980s, and prior to this protection were routinely shot, as it was believed that shooting goshawks would keep grouse populations high. In the United States, Goshawk were not shot as a management strategy. Though aggressive nest defense has been characterized throughout North America, goshawks in Finland do not show this same behavior. To quantify aggression, we presented nesting goshawks with an owl decoy, a human mannequin, and a live human and recorded their responses to each of the trial conditions. We used statistics to compare the two populations. Our results suggested that goshawks in Montana exhibit more aggressive nest defense behaviors than those in Finland. While this could be due to some biotic or abiotic factor that we were not able to control for in a study on such a small scale, it is also possible that the results from this study suggest another underlying cause, such as an artificial selection pressure created by shooting goshawks.As human impacts on wildlife have become a topic of increasing interest, studies have focused on issues such as overexploitation and habitat loss. However, little research has examined potential anthropogenic impacts on animal behavior. Understanding the degree to which human interaction may alter natural animal behavior has become increasingly important in developing effective conservation strategies. We examined two populations of northern goshawks (Accipiter gentilis) in Montana and Finland. Goshawks in Finland were not protected until the late 1980s, and prior to this protection were routinely shot, as it was believed that shooting goshawks would keep grouse populations high. In the United States, Goshawk were not managed as predator control. Though aggressive nest defense has been characterized throughout North America, goshawks in Finland do not show this same behavior. To quantify aggression, we presented nesting goshawks with an owl decoy, a human mannequin, and a live human and recorded their responses to each of the trial conditions. We evaluated the recordings for time of response, duration of response, whether or not an active stimulus was present to elicit the response (i.e., movement or sound), and the sex of the bird making the response. We used t-Test with unequal variance to compare mean number of responses and response duration. Our results suggested that goshawks in Montana exhibit more aggressive nest defense behaviors than those in Finland. While this could be due to some biotic or abiotic factor that we were not able to control for in a study on such a small scale, it is also possible that the results from this study suggest another underlying cause, such as an artificial selection pressure created by shooting goshawks.

Microscale Inorganic LED Based Wireless Neural Systems for Chronic in vivo Optogenetics.

Billions of neurons in the brain coordinate together to control trillions of highly convoluted synaptic pathways for neural signal processing. Optogenetics is an emerging technique that can dissect such complex neural circuitry with high spatiotemporal precision using light. However, conventional approaches relying on rigid and tethered optical probes cause significant tissue damage as well as disturbance with natural behavior of animals, thus preventing chronic in vivo optogenetics. A microscale inorganic LED (μ-ILED) is an enabling optical component that can solve these problems by facilitating direct discrete spatial targeting of neural tissue, integration with soft, ultrathin probes as well as low power wireless operation. Here we review recent state-of-the art μ-ILED integrated soft wireless optogenetic tools suitable for use in freely moving animals and discuss opportunities for future developments.

Observation of the Breeding Behavior of the Chinese Giant Salamander (Andrias davidianus) Using a Digital Monitoring System.

Simple SummaryBehavioral research on wild Chinese giant salamanders (Andrias davidianus) is in its infancy because A. davidianus inhabit underground river dens that are difficult to access. In order to ascertain the types of reproductive behavior exhibited by A. davidianus, this paper monitored their reproductive activity using a digital monitoring system in a simulated natural habitat. The survey uncovered reproductive behavior such as sand-pushing, showering, courtship, oviposition, and parental care. We also recorded the parental care time allocation for the first time. This study provides a scientific basis for the method optimization for the ecological reproduction of A. davidianus and the conservation of its wild population. This study also demonstrates that a digital monitoring system is an effective research method for investigating the behavior of Cryptobranchidae and other cave animals.Knowledge of natural animal behavior is essential for enhancing the protection and artificial breeding of animals. At present, the behavior of the Chinese giant salamander (Andrias davidianus) is studied through interviews with local people or occasional observations under artificial conditions, leading to a lack of systematic records. Thus, most reports are descriptive and lack quantitative analyses. To ascertain the types of reproductive activities and their corresponding time allocations, this study observed the reproductive behavior of A. davidianus using a digital monitoring system for the first time. The results showed that sand-pushing behavior is mainly carried out by the limbs, tail, head, and body of den-dominant males. Showering behaviors included rinsing the trunk, head, and tail. Courtship was composed of a series of behaviors, including standing side-by-side, belly colliding, mounting, mouth-to-mouth posturing, chasing, inviting, cohabitating, and rolling over. After chasing and interlocking with the male, the female discharged her eggs. The oviposition process began at either 02:04 or 04:09, and lasted either 66 or 182 min. Parental care included tail fanning, agitation, shaking, and eating dead and unfertilized eggs, and the durations of these behaviors accounted for 31.74 ± 4.35%, 17.42 ± 4.00%, 3.85 ± 1.18%, and 1.19 ± 0.69% of the entire incubation period, respectively. This paper reveals the characteristics of the reproductive behavior of A. davidianus and provides a scientific basis for the management of its ecological breeding and the conservation of its wild populations.

Cultural conformity generates extremely stable traditions in bird song

Cultural traditions have been observed in a wide variety of animal species. It remains unclear, however, what is required for social learning to give rise to stable traditions: what level of precision and what learning strategies are required. We address these questions by fitting models of cultural evolution to learned bird song. We recorded 615 swamp sparrow (Melospiza georgiana) song repertoires, and compared syllable frequency distributions to the output of individual-based simulations. We find that syllables are learned with an estimated error rate of 1.85% and with a conformist bias in learning. This bias is consistent with a simple mechanism of overproduction and selective attrition. Finally, we estimate that syllable types could frequently persist for more than 500 years. Our results demonstrate conformist bias in natural animal behaviour and show that this, along with moderately precise learning, may support traditions whose stability rivals those of humans.

TGA: Team game algorithm

Lately, there is a growing interest in conducting research on optimization algorithms due to their wide range of engineering applications. One of the optimization algorithms' categories is evolutionary algorithms which are inspired from the natural behavior of animals and humans. Further, each of the evolutionary algorithms has its own advantages and disadvantages in convergence accuracy and computational time. In the present paper, a novel solution search algorithm taken from the team games is introduced. This evolutionary algorithm named Team Game Algorithm (TGA) involves passing a ball, making mistakes and substitution operators. Comparing the TGA's results to the outcomes of other well-known algorithms for unimodal and multimodal test functions elucidates the successful design of the proposed heuristic algorithm.

Virtual spring damper method for nonholonomic robotic swarm self-organization and leader following

In this paper, we demonstrate a method for self-organization and leader following of nonholonomic robotic swarm based on spring damper mesh. By self-organization of swarm robots we mean the emergence of order in a swarm as the result of interactions among the single robots. In other words the self-organization of swarm robots mimics some natural behavior of social animals like ants among others. The dynamics of two-wheel robot is derived, and a relation between virtual forces and robot control inputs is defined in order to establish stable swarm formation. Two cases of swarm control are analyzed. In the first case the swarm cohesion is achieved by virtual spring damper mesh connecting nearest neighboring robots without designated leader. In the second case we introduce a swarm leader interacting with nearest and second neighbors allowing the swarm to follow the leader. The paper ends with numeric simulation for performance evaluation of the proposed control method.

Rapid whole brain imaging of neural activity in freely behaving larval zebrafish (Danio rerio).

The internal brain dynamics that link sensation and action are arguably better studied during natural animal behaviors. Here, we report on a novel volume imaging and 3D tracking technique that monitors whole brain neural activity in freely swimming larval zebrafish (Danio rerio). We demonstrated the capability of our system through functional imaging of neural activity during visually evoked and prey capture behaviors in larval zebrafish.

Proximity effect correction in electron-beam lithography based on computation of critical-development time with swarm intelligence

Electron-beam lithography (EBL) is an important technique in manufacturing high-resolution nanopatterns for broad applications. However, the proximity effect in EBL can degrade the pattern quality and, thus, impact the performance of the applications greatly. The conventional proximity effect correction (PEC) methods, which employ computationally intensive cell or path removal method for development simulation, are very computational lengthy, especially for complex and large-area patterns. Here, the authors propose a novel short-range PEC method by transforming the evaluation of pattern feasibility into the shortest path problem based on the concept of critical-development time. The authors combine this evaluation algorithm with the swarm intelligence which mimics the natural collective behavior of animals to optimize the design of electron dose distribution in EBL. The PEC algorithm is applied for pattern fabrication for U-shaped split-ring resonator and produces optimized exposure pattern that shows excellent agreement with the targeted objectives. Our work on the PEC strategy reduces the computational cost significantly and is particularly suitable for the design of complex pattern with various constraints.

A COMPARISON OF OPTIMIZATION ALGORITHMS FOR STANDARD BENCHMARK FUNCTIONS

Optimization algorithms are the search methods that are inspired from the natural biological evolution and social behavior of animals, insects, birds and humans, etc. The need of introducing the optimization algorithm is to achieve a near optimal solutions for complex and non-linear problems for which numerical methods may fail. This paper compares the performance of ten popular optimization algorithms: Grasshopper Optimization Algorithm, Adaptive Cuckoo Search Algorithm, Bird Swarm Algorithm, Chaotic Ant Lion Optimization Algorithm, Adaptive Wind Driven Algorithm, Real Coded Genetic Algorithm, Particle Swarm Optimization, Teaching Learning Based Optimization, Whale Optimization Algorithm and Ant Colony Optimization. A performance comparison of these optimization algorithms has been made on basis of accuracy by using five standard benchmark functions and it has been found that Whale Optimization Algorithm is performing better than other algorithms.

Modulation of Premotor and Primary Motor Cortical Activity during Volitional Adjustments of Speed-Accuracy Trade-Offs.

Recent work suggests that while animals decide between reaching actions, neurons in dorsal premotor (PMd) and primary motor (M1) cortex reflect a dynamic competition between motor plans and determine when commitment to a choice is made. This competition is biased by at least two sources of information: the changing sensory evidence for one choice versus another, and an urgency signal that grows over time. Here, we test the hypothesis that the urgency signal adjusts the trade-off between speed and accuracy during both decision-making and movement execution. Two monkeys performed a reaching decision task in which sensory evidence continuously evolves over the course of each trial. In different blocks, task timing parameters encouraged monkeys to voluntarily adapt their behavior to be either hasty or conservative. Consistent with our hypothesis, during the deliberation process the baseline and gain of neural activity in decision-related PMd (29%) and M1 cells (45%) was higher when monkeys applied a hasty policy than when they behaved conservatively, but at the time of commitment the population activity was similar across blocks. Other cells (30% in PMd, 30% in M1) showed activity that increased or decreased with elapsing time until the moment of commitment. Movement-related neurons were also more active after longer decisions, as if they were influenced by the same urgency signal controlling the gain of decision-related activity. Together, these results suggest that the arm motor system receives an urgency/vigor signal that adjusts the speed-accuracy trade-off for decision-making and movement execution. Significance statement: This work addresses the neural mechanisms that control the speed-accuracy trade-off in both decisions and movements, in the kinds of dynamic situations that are typical of natural animal behavior. We found that many "decision-related" premotor and motor neurons are modulated in a time-dependent manner compatible with an "urgency" signal that changes between hasty and conservative decision policies. We also found that such modulation influenced cells related to the speed of the reaching movements executed by the animals to report their decisions. These results suggest that a unified mechanism determines speed-accuracy trade-off adjustments during decision-making and movement execution, potentially influencing both the cognitive and motor aspects of reward-oriented behavior.

Big-Picture Biomimetics [Editorial

Discusses the significance of biomimetics for research and development products, services, and applications that are based on observing the natural world and animal behaviors.

Long-term Behavioral Tracking of Freely Swimming Weakly Electric Fish

Long-term behavioral tracking can capture and quantify natural animal behaviors, including those occurring infrequently. Behaviors such as exploration and social interactions can be best studied by observing unrestrained, freely behaving animals. Weakly electric fish (WEF) display readily observable exploratory and social behaviors by emitting electric organ discharge (EOD). Here, we describe three effective techniques to synchronously measure the EOD, body position, and posture of a free-swimming WEF for an extended period of time. First, we describe the construction of an experimental tank inside of an isolation chamber designed to block external sources of sensory stimuli such as light, sound, and vibration. The aquarium was partitioned to accommodate four test specimens, and automated gates remotely control the animals' access to the central arena. Second, we describe a precise and reliable real-time EOD timing measurement method from freely swimming WEF. Signal distortions caused by the animal's body movements are corrected by spatial averaging and temporal processing stages. Third, we describe an underwater near-infrared imaging setup to observe unperturbed nocturnal animal behaviors. Infrared light pulses were used to synchronize the timing between the video and the physiological signal over a long recording duration. Our automated tracking software measures the animal's body position and posture reliably in an aquatic scene. In combination, these techniques enable long term observation of spontaneous behavior of freely swimming weakly electric fish in a reliable and precise manner. We believe our method can be similarly applied to the study of other aquatic animals by relating their physiological signals with exploratory or social behaviors.

The Emotional Lives of Animals and Children: Insights from a Farm Sanctuary by William Crain

 2014 Children, Youth and Environments Children, Youth and Environments 24(3), 2014 The Emotional Lives of Animals and Children: Insights from a Farm Sanctuary William Crain (2014). San Francisco, CA: Turning Stone Press, 137 pages. $15.95; ISBN 978-1-61852-082-1. In 2008, William Crain, a professor of psychology at City University of New York and author of a popular child development textbook, bought “a broken-down farm with a few acres of pasture in lower Duchess County, New York” (xvi) and turned it into Safe Haven Farm Sanctuary. This place provides a home for over 70 rescued farm animals that escaped factory farms and slaughterhouses and found their way (or were brought) to the Sanctuary. Crain recounts how he gradually became committed to animal welfare, as well as vegetarianism, and together with his wife Ellen, a pediatrician, devoted themselves to the Farm Sanctuary. At the same time, Crain, as a professor of psychology, wanted to study animals’ natural behavior. He thought that observing these farm animals could illuminate aspects of children’s development as well. Thus, Crain and his wife became participant observers in the lives of chickens, goats, sheep and other farm animals, as well as the humans who came to the farm. In Part I of this book, Crain addresses the emotions that he has observed in the rescued farm animals under his care. His concept of emotion is unusually broad; it includes not only fear, but play, freedom, care, spirituality, and resilience. In each chapter, he draws parallels between the emotions observed in farm animals and those of children, underscoring the commonalities across species. For example, he recounts how some animals and children fall silent for extended periods after a trauma and only begin to vocalize when they feel safe. Crain is sensitive to distinctions between child and animal behavior, and finds in the animal example useful lessons for enhancing child development. For example, he contrasts the “watchful waiting” of mother goats who are content to stay on the sidelines as their baby goats scamper and play, with the “helicopter parenting” of many contemporary humans. Crain argues that uninhibited free play is innate and adaptive across most mammalian species. Hence, humans would do well to emulate these mother goats. When Crain discusses the need for freedom, he wrestles the urge to grant his rescued flock maximum freedom against the very real dangers to those animals (from foxes, for example) if he were to do so. Similarly, he argues, one must find the right balance between freedom and safety for human children. Book Review: The Emotional Lives of Animals and Children: Insights… 250 In elaborating this theme of the commonalities between these farm animals and children, Crain can, on occasion, stretch the parallels. For example, he argues that just as humans, including children, derive a sense of calm, awe and serenity—what Crain calls “spirituality”—from gazing at landscapes, some animals also gaze out at nature with what seem to be similar feelings. This cannot be ruled out; however, there is no empirical evidence to support such a claim. Moreover, landscapes may evoke many different emotions, not all of them linked to spirituality. Even the same landscape may be at times threatening, as during a storm, or welcoming, as in a bright, temperate day. However, this caution aside, the major point Crain is emphasizing is well worth considering. Humans are animals after all, and share much with other species. We can learn a great deal about children by observing the natural behavior of other animals. In Part II, Crain draws from his observations to urge that we help children build a more connected, inclusive and egalitarian relationship with animals. In his view, applying a sharp hierarchy that places humans above animals and viewing animals from a utilitarian perspective have many damaging effects on children as well as animals. By according animals greater status and respect, viewing them as having intrinsic worth, children will become more connected to the natural world and will not lose their ethical stance toward animals. Crain concludes that society needs a more inclusive value system, one that includes animals as well as humans. Where might that more inclusive value system come...

A behavioral comparison of the common laboratory rat strains Lister Hooded, Lewis, Fischer 344 and Wistar in an automated homecage system

Behavioral characterization is an important part of establishing novel animal models, but classical behavioral tests struggle to reveal conclusive results due to problems with both reproducibility and validity. On the contrary, automated homecage observations are believed to produce robust outcomes that relate more to natural animal behavior. However, information on the behavior of background strains from such observations, which could provide important reference material, is rare. For this reason, we compared the behavior of the commonly used Lister Hooded, Lewis, Fischer 344 and Wistar rats during 70 h of exposure to an automated homecage system at 2, 4 and 6 months of age. We found considerable strain differences in metabolic parameters, novelty-induced and baseline activity-related behavior as well as differences in the development of these parameters with age. The results are discussed in terms of advantages and disadvantages of the system compared to classical behavioral tests, as well as the system's ability to recreate common findings in literature.

Size matters: Filamentous bacteria drive interstitial vortex formation and colony expansion in Paenibacillus vortex

The beautiful patterns formed by motile bacteria have always intrigued the curious (Ben-Jacob et al., Eur. Phys. J. B 2008;65:315-322). The mechanisms underlying their formation are believed to play a role in a range of natural phenomena, including embryogenesis, animal behavior, and economics. There has been significant effort to develop tools for characterizing the behavior of individual cells within large populations of migrating bacteria; a prerequisite for studying self-organization in this context (Garner, Mol. Micro. 2011;80:577-579). Here, I apply powerful computer vision methods to study P. vortex interstitial colony expansion. Quantitative observations show how exceptionally long bacteria play a catalytic role-both in vortex formation, which had to date remained somewhat mysterious-and in facilitating colony expansion. This highlights the functional importance of bacterial morphology in bridging the microscopic and macroscopic scales, and it reshapes our understanding of vortex-forming bacteria.