Animal Behavior Research Research Articles

Ethology adopts the STRANGE framework for animal behaviour research, to improve reporting standards

<i>Ethology</i> adopts the STRANGE framework for animal behaviour research, to improve reporting standards

Impacts of Whale Watching on the Behavior of Humpback Whales (Megaptera novaeangliae) in the Coast of Panama

Ecotourism focused on whales and dolphins has become a popular activity and an important source of revenue for many countries. Whale watching is vital to supporting conservation efforts and provides numerous benefits to local communities including educational opportunities and job creation. However, the sustainability of whale-based ecotourism depends on the behavior and health of whale populations and it is crucial that ecotourism industries consider the impact of their activities on whale behavior. To address this statement, we collected behavioral data (e.g., change in swimming direction, frequency of breaching, slap behaviors, diving, and spy hops) from humpback whales (Megaptera novaeangliae) in the marine protected area of Las Perlas Archipelago off the Pacific coast of Panama. The goal was to determine if tourist vessel presence had an influence on whale behaviors. We conducted this study during the humpback whale breeding season from August through September 2019. Based on 47 behavioral observations, we found that higher boat density corresponded with humpback whales’ frequency of direction changes, which based on previous literature is believed to be a sign of disturbance. Alternatively, no changes in behavior were observed with varying boat density. This result is important given Panamanian regulations first implemented in 2007 by Resolution AMD/ARAP No. 01, 2007 prohibit whale-based tourism from disturbing whales, which is explicitly measured by changes in whale behavior. Because there is no systematic monitoring of whale watching activity to enforce the regulations, there is currently little compliance from tour operators and tourists. The integration of animal behavior research into management planning should result in more effective regulation and compliance of such conservation policies.

Measuring attention in rats with a visual signal detection task: Signal intensity vs. signal duration

Measurement of attentional performance in animal behavioral research allows us to investigate neural mechanisms underlying attentional processes and translate results to better understand human attentional function, dysfunction and drug treatments to reverse dysfunction. One useful method to measure attention in experimental animal studies is to use an operant visual signal detection paradigm, consisting of two levers and the rapid flashing of a cue lamp to signal a reward. In this study, we tested the relative sensitivity of this task when using different variants of the stimulus signal, varying brightness or duration of the light cue. To investigate roles of different neural systems underlying attentional processes, we assessed the sensitivity of attentional performance with these two different cue variations with blockade of muscarinic acetylcholine and NMDA glutamate receptors with scopolamine and MK-801 (dizocilpine). Operant signal detection was tested using a signal light that varied in intensity (0.027, 0.269, 1.22 lx) of the signal light or in a paradigm which varied the duration (0.5 s, 1 s, 2 s) of the signal light. Both methods of assessing attention showed construct validity for producing gradients of accuracy for signal detection; the dimmest cue led to less accurate responding compared to the brighter cues, and the shortest duration led to less accuracy compared to the longer durations. However, the tests differed in their sensitivity to pharmacological disruption. With the duration test, the high dose of MK-801 along with co-exposure of scopolamine and MK-801 caused a significant reduction of hit and rejection accuracy. Conversely, the intensity variation test did not show significant differences as a function of drug exposures. These data suggest that changes in signal duration, rather than signal intensity, during operant signal detection may have higher sensitivity to detecting drug effects and be a more useful technique for examining pharmacological interventions on attentional behavior and performance.

Editorial: Pre-registration and Assessing Effects of Commonly Used Techniques in Animal Behavior Research

Editorial: Pre-registration and Assessing Effects of Commonly Used Techniques in Animal Behavior Research

What makes neurophysiology meaningful? Semantic content ascriptions in insect navigation research

In the course of investigating the living world, biologists regularly attribute semantic content to the phenomena they study. In this paper, I examine the case of a contemporary research program studying the navigation behaviors of ants and develop an account of the norms governing researchers’ ascriptions of semantic content in their research practices. The account holds that researchers assign semantic content to behaviors that reliably achieve a difficult goal-directed function, and it also suggests a productive role for attributions of semantic content in the process of animal behavior research.

Opportunistic predation reveals a hidden cost of fighting in birds

Predation risk is often hypothesized to be a cost of escalated fighting, and it relies on the assumption that predators eavesdrop on distracted prey. However, there is no direct evidence supporting these two ideas. Here, I report a predation event that occurred immediately after escalated fighting in birds. Two Rufous Horneros (Furnarius rufus) were engaged in a contest on the ground, while a third hornero watched from a close by (~ 3 m) perch. The hornero that won the contest, having strongly pecked its opponent, then joined the third hornero on the perch. The loser hornero appeared to be injured or fatigued after fighting and crouched motionless, wings down, and belly touching the ground. Approximately 10 s after the fight, a large Aplomado Falcon (Falco femoralis) suddenly flew toward the loser hornero, caught the bird, and flew away. This casual predation record indicates the falcon was eavesdropping on these horneros’ contest, possibly using the opportunity to attack the loser hornero which, due to being injured or fatigued after the contest, was more vulnerable to predation. This anecdotal evidence indicates the existence of a predation cost associated with escalated fighting, stressing the importance of natural history records in animal behavior research.

It's not just the animals that are STRANGE.

A "STRANGE" framework has been proposed to mitigate the effects of sampling biases in animal experiments (Webster & Rutz, Nature, 582, 337-340, 2020). While sampling biases are likely a major cause of poor replicability and generalizability in animal behavior research, a more comprehensive and cautious approach is needed to effectively guide decision-making in animal research.

A New Method of Aquatic Animal Personality Analysis Based on Machine Learning (PAML): Taking Swimming Crab Portunus trituberculatus as an Example

Personality differences are an important part of animal behavior research and a potential factor affecting the physiochemical response of animals to stimuli. Therefore, accurate classification of personality has an impact on animal experiment research that cannot be ignored. However no completely objective methods have been noticed hitherto to be employed in aquatic animal personality studies. To address this issue, we established a personality analysis method based on machine learning (PAML) to avoid the influence of subjective factors. Then we analyzed the personality changes of swimming crab Portunus trituberculatus exposed to external stimuli i.e. food deprivation. Results showed that the high-accuracy PAML method could provide a comprehensive understanding of crab personality classification. Based on PAML, the personality of P. trituberculatus was detected to change dynamically under stress. After analyzing three typical personality characteristics: boldness, activity and hesitancy, we found that the stability of boldness was the strongest, which is the best single candidate for personality evaluation, while the activity changed greatly under stress. This study confirms that animal personality changes dynamically with external factors. Based on PAML, we can not only avoid subjective factors and improve classification accuracy, but also quantitatively trace the dynamic influence of external factors on aquatic animal personality.

Editorial: The Value and Status of Replications in Animal Behavior and Cognition Research

Editorial: The Value and Status of Replications in Animal Behavior and Cognition Research

Identification of the possible sites of memory storage within live rodents

Different research in animal behavior demonstrate that amygdala, a heterogynous region in brain is related to sensitive response, incorporating input signals and initiating events associated to them. Impairment in this region can be responsible for emotional disorders in humans and social behavior. There are many experiments performed using rodents throughout the globe every day. Most of these experiments involve the death of rodents. These rodents are specifically kept for experiments related to immune system. The transgenic rodents have weak immune system as this system is disabled in them by manipulating the neurons and DNA associated with the immune system. Fear has been selected as a behaviour trait because it is widely considered as an attribute increasing survival and reproductive progress. This review article studies and highlights different research related to identify memory storage sites in rodents, its history, development and different procedures used for the process.

Comparisons of Animal “Smart” Using The First Four Stages of the Model of Hierarchical Complexity

The Model of Hierarchical Complexity is a behavioral model of development and evolution of the complexity of behavior. It is based on task analysis. Tasks are ordered in terms of their hierarchical complexity, which is an ordinal scale that measures difficulty. The hierarchical difficulty of tasks is categorized as the order of hierarchical complexity. Successful performance on a task is called the behavioral stage. This model can be applied to non-human animals, and humans. Using data from some of the simplest animals and also somewhat more complex ones, this analysis describes the four lowest behavioral stages and illustrate them using the behaviors of a range of simple organisms. For example, Stage 1 tasks, and performance on them, are addressed with automatic unconditioned responses. Behavior at this Stage includes sensing, tropisms, habituation and, other automatic behaviors. Single cell organisms operate at this Stage. Stage 2 tasks include these earlier behaviors, but also include respondent conditioning but not operant conditioning. Animals such as some simple invertebrates have shown respondent conditioning, but not operant conditioning. Stage 3 tasks coordinate three instances of these earlier tasks to make possible operant conditioning. These stage 3 performances are similar to those of some invertebrates and also insects. Stage 4 tasks organisms coordinate 2 or more circular sensory-motor task actions into a superordinate “concept”. This explanation of the early stages of the Model of Hierarchical Complexity may help future research in animal behavior, and comparative psychology.

Conditions for assessing cortisol in sheep: the total form in blood v. the free form in saliva

Cortisol is often used as a stress indicator in animal behaviour research. Cortisol is commonly measured in plasma and can also be measured in saliva. Saliva contains only the free form of cortisol, which is biologically active, and saliva sampling is not invasive and may therefore be less stressful. Our study aims to guide the choice between the measurements of cortisol in plasma v. saliva depending on experimental conditions. We analysed the effect of the level of cortisol in plasma on the concentration of cortisol in saliva compared to plasma and the effect of saliva sampling v. jugular venepuncture on the cortisol response. In Experiment 1, blood and saliva were collected simultaneously under conditions in which the expected cortisol release in blood varied: in an undisturbed situation or after the isolation of lambs from their pens or the administration of exogenous ACTH (six animals per treatment). In Experiment 2, we subjected lambs to saliva sampling, venepuncture or neither of these for 8 days to evaluate how stressful the sampling method was and whether the animals habituated to it by comparing the responses between the first and last days (four animals per treatment). All animals were equipped with jugular catheters to allow regular blood sampling without disturbance. Samples were collected 15 min before any treatment was applied, then at various time points up to 135 min in Experiment 1 and 45 min in Experiment 2. In Experiment 1, we observed a strong correlation between salivary and plasma cortisol concentrations (r = 0.81, P < 0.001). The ratio between salivary and plasma cortisol concentrations was 0.106 on average. This ratio was higher and more variable when the cortisol concentration in plasma was below 55 nmol/l. In Experiment 2, venepuncture induced a larger cortisol response than saliva sampling or no intervention on day 1 (P < 0.02); this difference was not observed on day 8, suggesting that sheep habituated to venepuncture. We recommend the measurement of cortisol in saliva to avoid stressing animals. However, when the expected concentration in plasma is below 55 nmol/l, the cortisol in saliva will reflect only the free fraction of the cortisol, which may be a limitation if the focus of the experiment is on total cortisol. In addition, if cortisol is measured in plasma and blood is collected by venepuncture, we recommend that sheep be habituated to venepuncture, at least to the handling required for a venepuncture.

From Flatworms to Humans: Demonstration of Learning Principles Using Activities Developed by the Laboratory of Comparative Psychology and Behavioral Biology – Additional Exercises

Since the mid-1990s, the Laboratory of Comparative Psychology and Behavioral Biology at Oklahoma State University has developed a number of exercises appropriate for classroom use to demonstrate principles of learning and other forms of behavior. These activities have primarily focused on the use of invertebrates such as planarians, houseflies, earthworms, and honey bees. We have also developed exercises using fish based on an inexpensive apparatus called the “Fish Stick.” Other exercises to be discussed are “Salivary Conditioning in Humans;” “Project “Petscope” which turns local pet stores into animal behavior research centers; “Prey Preferences in Snakes”; and “Correspondence in the Classroom” which helps students learn to write letters to scientists in the field of learning research. These various teaching activities are summarized, and the advantages and limitations are discussed. Additional material developed since 2011 is included. This material includes a low cost microcontroller, history of comparative psychology projects, and additional animal exercises.

A Model for Animal Home Range Estimation Based on the Active Learning Method

Home range estimation is the basis of ecology and animal behavior research. Some popular estimators have been presented; however, they have not fully considered the impacts of terrain and obstacles. To address this defect, a novel estimator named the density-based fuzzy home range estimator (DFHRE) is proposed in this study, based on the active learning method (ALM). The Euclidean distance is replaced by the cost distance-induced geodesic distance transformation to account for the effects of terrain and obstacles. Three datasets are used to verify the proposed method, and comparisons with the kernel density-based estimator (KDE) and the local convex hulls (LoCoH) estimators and the cross validation test indicate that the proposed estimator outperforms the KDE and the LoCoH estimators.

Mahout Perspectives on Asian Elephants and Their Living Conditions

Simple SummaryMahouts, often known as elephant handlers, or by other terms, such as oozie in Myanmar, work closely with captive Asian elephants in elephant range countries. This work usually involves taking responsibility for just one elephant. The daily tasks of mahouts can include feeding, cleaning or bathing elephants, treating minor medical conditions, participating in training, and riding elephants in order for them to achieve specific tasks, such as transportation of materials, religious functions, or tourism activities. Because of their close interactions with elephants, mahouts have knowledge of elephants that stretches from the cultural to the behavioral and ecological. In this study, I interviewed mahouts in their own languages with a translator, using a mix of short and open-ended questions. The second kind of questions allowed mahouts to elaborate in as much detail as they wanted on their experience. The methods allowed me to collect perspectives on welfare and the associations with elephants in Nepal. I also asked questions about how long they had worked with elephants and how many elephants they worked with. The mahouts were not a uniform group, with differences in age, experience, and perspectives. The mahouts gave their most extensive comments when discussing elephant welfare, particularly on the use of fenced enclosures versus chains, elephant diet, and interactions with domestic animals. The input of mahouts could be useful for proposing and implementing plans for elephant welfare in range countries.The skills, knowledge, and expertise of mahouts have been recognized by organizations and individual managers who are responsible for captive elephants and by academics, where they have been a source of studies from the ethnographic to animal behavior research. In this study, I used semi-structured interviews in local languages to explore individual experiences of mahouts in Nepal. I also investigated perspectives on elephant welfare, including the use of corral (fenced) enclosures. I undertook a further key informant interview in English to gain more discursive perspectives on the topics. Our results revealed that mahouts at the study site are unlikely to come from multi-generational families of mahouts. All mahouts referenced the religious significance of elephants in their country when describing broader local perspectives. Many mahouts explained both positive and negative implications for differing strategies in housing captive elephants, often balanced the competing interests of elephant welfare with their own need for elephants to follow verbal communication, and their responsibility for the safety of the elephants, other staff, and tourists. The fine-balancing perspectives of mahouts, taking both humans and elephants into account, underlines their role as an important source of knowledge of captive Asian elephants in range countries, and their potential role as co-producers of research linked to welfare. This approach could also be of relevance to the welfare of ex-situ Asian elephants.

Accounting for pseudoreplication is not possible when the source of nonindependence is unknown

Repeated observations of the same individuals or other units, which can lead to clustered observations, are common in animal behaviour research, and mixed models are commonly employed to model and account for such clustering in the data and avoid pseudoreplication. However, in some cases, while the data might comprise repeated samples from the same individuals, the precise identity of the individuals from which samples originated is unknown. In a recent paper Garamszegi (2016, Animal Behaviour, 120, 223–234) suggested an approach to account for pseudoreplication which is based on repeatedly assigning random subject identities to the samples and then analysing the data using a mixed model or averaged values for each randomly assigned identity. Here we tested this approach using a simulation study. We found that the approach suggested by Garamszegi leads to clearly inflated type I error rates that were essentially the same as those obtained from a naïve linear model simply ignoring individual identity and that only a model based on the correct subject identities roughly produced the nominal type I error rate. We conclude that, currently, there is no method available that allows pseudoreplication to be controlled when subject identities are unknown.

Von Uexküll Revisited: Addressing Human Biases in the Study of Animal Perception.

More than 100 years ago, the biologist Jakob von Uexküll suggested that, because sensory systems are diverse, animals likely inhabit different sensory worlds (umwelten) than we do. Since von Uexküll, work across sensory modalities has confirmed that animals sometimes perceive sensory information that humans cannot, and it is now well-established that one must account for this fact when studying an animal's behavior. We are less adept, however, at recognizing cases in which non-human animals may not detect or perceive stimuli the same way we do, which is our focus here. In particular, we discuss three ways in which our own perception can result in misinformed hypotheses about the function of various stimuli. In particular, we may (1) make untested assumptions about how sensory information is perceived, based on how we perceive or measure it, (2) attribute undue significance to stimuli that we perceive as complex or striking, and (3) assume that animals divide the sensory world in the same way that we as scientists do. We discuss each of these biases and provide examples of cases where animals cannot perceive or are not attending to stimuli in the same way that we do, and how this may lead us to mistaken assumptions. Because what an animal perceives affects its behavior, we argue that these biases are especially important for researchers in sensory ecology, cognition, and animal behavior and communication to consider. We suggest that studying animal umwelten requires integrative approaches that combine knowledge of sensory physiology with behavioral assays.

Perception of artificial conspecifics by bearded dragons (Pogona vitticeps).

Artificial animals are increasingly used as conspecific stimuli in animal behavior research. However, researchers often have an incomplete understanding of how the species under study perceives conspecifics, and, hence, which features are needed for a stimulus to be perceived appropriately. To investigate the features that bearded dragons (Pogona vitticeps) attend to, we measured their lateralized eye use when assessing a successive range of stimuli. These ranged through several stages of realism in artificial conspecifics, to see how features such as color, the presence of eyes, body shape and motion influence behavior. We found differences in lateralized eye use depending on the sex of the observing bearded dragon and the artificial conspecific, as well as the artificial conspecific's behavior. Therefore, this approach can inform the design of robotic animals that elicit biologically-meaningful responses in live animals.

What are we measuring? Novices agree amongst themselves (but not always with experts) in their assessment of dog behaviour

AbstractHumans differ in how they perceive, assess, and measure animal behaviour. This is problematic because strong observer bias can reduce statistical power, accuracy of scientific inference, and in the worst cases, lead to spurious results. Unfortunately, reports and studies of measurement reliability in animal behaviour studies are rare. Here, we investigated two aspects of measurement reliability in working dogs: inter‐observer agreement and criterion validity (comparing novice ratings with those given by experts). Here, we extend for the first time a powerful framework used in human psychological studies to investigate three potential aspects of (dis)agreement in nonhuman animal behaviour research: (a) that some behaviours are easier to observe than others; (b) that some subjects are easier to observe than others; and (c) that observers with different levels of experience with the subject animal give the same or different ratings. We found that novice observers with the same level of experience agreed upon measures of a wide range of behaviours. We found no evidence that age of the dogs affected agreement between these same novice observers. However, when observers with different levels of experience (i.e., novices vs. a working dog expert) assessed the same dogs, agreement appeared to be strongly affected by the measurement instrument used to assess behaviour. Given that animal behaviour research often utilizes different observers with different levels of experience, our results suggest that further tests of how different observers may measure behaviour in different ways are needed across a wider variety of organisms and measurement instruments.

Do differences in ecological conditions influence grouping behaviour in a solitary ungulate, the Japanese serow?

Abstract One aim of animal behaviour research is to explain why animals live in groups. The grouping behaviour of solitary mammals is important for understanding the ecological factors promoting the evolution of sociality. We present field data of Japanese serow, a primitive solitary ungulate, in forest and alpine meadow habitats. We found no differences in group size of all age–sex classes between the forest and alpine meadow habitats, and both populations were mainly solitary. The current findings suggest that group size in the serow is not affected by ecological conditions, including habitat structure, forage abundance, and population density. However, female associations involving up to three females occurred in the alpine meadow habitat throughout the year, whereas such groupings were not observed in the forest habitat. This finding suggests that abundant food supply in the alpine meadow promoted female associations by decreasing the cost of food resource competition.