Need or opportunity? A study of innovations in equids

Funding: The article processing charge was funded by the Baden-Württemberg Ministry of Science, Research and Culture and the Nürtingen-Geislingen University, in the funding programme Open Access Publishing.Debate persists over whether animals develop innovative solutions primarily in response to needs or conversely whether they innovate more when basic needs are covered and opportunity to develop novel behaviour is offered. We sourced 746 cases of “unusual” behaviour in equids by contacting equid owners and caretakers directly and via a website (https://innovative-behaviour.org), and by searching the internet platforms YouTube and Facebook for videos. The study investigated whether differences in need or opportunity for innovation were reflected in the numbers of different types of innovations and in the frequencies of repeating a once-innovative behaviour (i) with respect to the equids’ sex, age, and breed type, (ii) across behavioural categories, and whether (iii) they were affected by the equids’ management (single vs group housing, access to roughage feed, access to pasture, and social contact). We found that the numbers of different types of innovation and the frequency of displaying specific innovations were not affected by individual characteristics (sex, age, breed or equid species). Few types of innovation in escape and foraging contexts were observed, whilst the comfort, play, and social contexts elicited the greatest variety of innovations. We also found higher numbers of different types of innovations in horses kept in groups rather than in individual housing, and with unlimited rather than with restricted access to pasture and roughage. Equids in permanent social contact performed high rates of once-innovative behaviour. We suggest that equids produce goal-directed innovations and repeat the behaviour at high frequency in response to urgent needs for food and free movement or when kept in conditions with social conflict. However, equids devise the greatest variety of innovations when opportunity to play and to develop comfort behaviour arises and when kept in good conditions.Publisher PDFPeer reviewe

Sex and Age Don't Matter, but Breed Type Does—Factors Influencing Eye Wrinkle Expression in Horses

Identifying valid indicators to assess animals' emotional states is a critical objective of animal welfare science. In horses, eye wrinkles above the eyeball have been shown to be affected by pain and other emotional states. From other species we know that individual characteristics, e.g., age in humans, affect facial wrinkles, but it has not yet been investigated whether eye wrinkle expression in horses is systematically affected by such characteristics. Therefore, the aim of this study was to assess how age, sex, breed type, body condition, and coat colour affect the expression and/or the assessment of eye wrinkles in horses. To this end, we adapted the eye wrinkle assessment scale from Hintze et al. (1) and assessed eye wrinkle expression in pictures taken from the left and the right eye of 181 horses in a presumably neutral situation, using five outcome measures: a qualitative first impression reflecting how worried the horse is perceived by humans, the extent to which the brow is raised, the number of wrinkles, their markedness and the angle between a line through both corners of the eye and the topmost wrinkle. All measures could be assessed highly reliable with respect to intra- and inter-observer agreement. Breed type affected the width of the angle [F(2,114) = 8.20, p < 0.001], with thoroughbreds having the narrowest angle (M = 23.80, SD = 1.60), followed by warmbloods (M = 28.00, SD = 0.60), and coldbloods (M = 31.00, SD = 0.90). None of the other characteristics affected any of the outcome measures, and eye wrinkle expression did not differ between the left and the right eye area (all p-values > 0.05). In conclusion, horses' eye wrinkle expression and its assessment in neutral situations was not systematically affected by the investigated characteristics, except for “breed type”, which accounted for some variation in “angle”; how much eye wrinkle expression is affected by emotion or perhaps mood needs further investigation and validation

Die sensorische Lateralität als Indikator für emotionale und kognitive Reaktionen auf Umweltreize beim Tier. The use of sensory laterality for indicating emotional and cognitive reactions on environmental stimuli in animals

Zusammenfassung Viele Tiere zeigen eine eindeutige sensorische Lateralität, sprich sie benutzen bevorzugt ein Auge, ein Ohr, oder eine Nüster zur Aufnahme von Sinneseindrücken. Dies korreliert in den meisten Fällen nicht mit der motorischen Lateralität, sondern wird viel mehr durch die einseitige Verarbeitung von Informationen in den jeweiligen Gehirnhemisphären bedingt. So werden emotionale Reaktionen von der rechten, reaktiven Gehirnhemisphäre und rationale Reaktionen von der linken, kognitiven Gehirnhemisphäre gesteuert. Da die Gehirnhälften zum Großen Teil mit den kontrolateralen Sinnesorganen verbunden sind lässt die Seite mit welcher Sinneseindrücke aufgenommen werden Schlüsse auf deren Informationsgehalt zu. So zeigen Tiere bei linksseitiger Aufnahme von Sinneseindrücken vermehrt reaktive, emotionalen Reaktionen, wie etwa bei Angst oder freudige Erregung, und bei rechtsseitig aufgenommene Sinneseindrücke eher rationales, gesteuertes Verhalten. Zudem verstärkt sich die sensorische Lateralität wenn Tiere Stress erfahren, sprich wenn sie wiederholt mit Situationen anthropogenen oder natürlichen Ursprungs konfrontiert werden denen sie nicht gewachsen sind, wie etwa bei unpassenden Haltungs- und Trainingsbedingungen, oder bei unausweichlichem Raubtierdruck und sozialer Konkurrenz. Eine stark ausgeprägte, zunehmende sensorische Lateralität kann daher auf ein beeinträchtigtes Wohlergehen der Tiere hinweisen. Summary Many animals are lateralized when using sensory organs such as the eyes, ears or nostrils. Sensory laterality is not, as previously believed, caused by adjustment to motor laterality, but rather by one sided information processing in the particular brain hemispheres. While the right hemisphere predominantly analyses emotional information, the left hemisphere governs controlled rational, cognitive decisions. Since the brain hemispheres are largely connected with contralateral sensory organs, it is possible to infer how the information may be being interpreted by the side of preferred eye, ear or nostril used. The left eye usually dominates in emotional situations, i.e. fear or positive excitement, and the right eye in rational situations. Moreover, laterality increases when animals are stressed, e.g. when animals are confronted with anthropogenic or natural factors they can not handle, such as unsuitable housing or training conditions or unavoidable predation pressure and social competition. A strong or increasing laterality could therefore potentially indicate welfare issues

Animal behaviour in a human world : a crowdsourcing study on horses that open door and gate mechanisms

This research received funding from the Ministry of Science, Research and Art (MWK), Baden-Württemberg, Germany.Anecdotal reports of horses opening fastened doors and gates are an intriguing way of exploring the possible scope of horses’ problem-solving capacities. The species’ natural environment has no analogues of the mechanisms involved. Scientific studies on the topic are missing, because the rate of occurrence is too low for exploration under controlled conditions. Therefore, we compiled from lay persons case reports of horses opening closed doors and gates. Additionally, we collected video documentations at the internet platform YouTube, taking care to select raw data footage of unedited, clearly described and clearly visible cases of animals with no distinct signs of training or reduced welfare. The data included individuals opening 513 doors or gates on hinges, 49 sliding doors, and 33 barred doors and gateways; mechanisms included 260 cases of horizontal and 155 vertical bars, 43 twist locks, 42 door handles, 34 electric fence handles, 40 carabiners, and 2 locks with keys. Opening was usually for escape, but also for access to food or stable-mates, or out of curiosity or playfulness. While 56 percent of the horses opened a single mechanism at one location, 44 percent opened several types of mechanism (median = 2, min. = 1, max. = 5) at different locations (median = 2, min. = 1, max. = 4). The more complex the mechanism was, the more movements were applied, varying from median 2 for door handles to 10 for carabiners. Mechanisms requiring head- or lip-twisting needed more movements, with significant variation between individuals. 74 horses reported in the questionnaire had options for observing the behaviour in stable mates, 183 did not, which indicates that the latter learned to open doors and gates either individually or from observing humans. Experience favours opening efficiency; subjects which opened several door types applied fewer movements per lock than horses which opened only one door type. We failed to identify a level of complexity of door-fastening mechanism that was beyond the learning capacity of the horse to open. Thus, all devices in frequent use, even carabiners and electric fence handles, are potentially vulnerable to opening by horses, something which needs to be considered in relation to keeping horses safely.Publisher PDFPeer reviewe

Social learning across species - horses (Equus caballus) learn from humans by observation

This study examines whether horses can learn by observing humans, given that they identify individual humans and orientate on the focus of human attention. We tested 24 horses aged between 3 and 12. Twelve horses were tested on whether they would learn to open a feeding apparatus by observing a familiar person. The other 12 were controls and received exactly the same experimental procedure, but without a demonstration of how to operate the apparatus. More horses from the group with demonstration (8/12) reached the learning criterion of opening the feeder twenty times consecutively than horses from the control group (2/12), and younger horses seemed to reach the criterion more quickly. Horses not reaching the learning criteria approached the human experimenters more often than those that did. The results demonstrate that horses learn socially across species, in this case from humans

The role of an alpha animal in changing environmental conditions

The maintenance and development of conservation areas by grazing of large herbivores, such as Przewalski’s horses is common practice. Several nature conservation areas house male bachelor groups. When males are needed for breeding they are removed from the groups, often without considering group compositions and individual social positions. However, alpha animals are needed for ensuring group stability and decision making in potentially dangerous situations in several species. To investigate the importance of the alpha male in a bachelor group, we observed the behaviour of five Przewalski’s horse males during the enlargement of their enclosure. We analyzed the group’s social structure and movement orders, as well as the animals’ connectedness, activity budgets, and whether they moved with preferred group members and how factors such as social rank influenced the horses’ behaviour. We also investigated the excretion of glucocorticoid metabolites (CM) via faeces of the horses while exploring a new area as a parameter of glucocorticoid production. Our results show that the alpha male is important for a bachelor group in changing environmental conditions. The alpha male had the highest level of connectedness within the group. When exploring the new environment, its position in the group changed from previously being the last to being the first. Furthermore the whole group behaviour changed when exploring the new area. The stallions showed reduced resting behavior, increased feeding and did not stay close to each other. We found that the excretion of glucocorticoid metabolites of most horses rose only marginally during the first days on the new area while only the alpha male showed a significant increased amount of glucocorticoid production during the first day of the enclosure enlargement

Context-dependent third-party intervention in agonistic encounters of male Przewalski horses Short title: Third-party intervention in Przewalski horses

One mechanism to resolve conflict among group members is third party intervention, for which several functions, such as kin protection, alliance formation, and the promotion of group cohesion have been proposed. Still, empirical research on the function of intervention behaviour is rare. We studied 40 cases of intervention behaviour in a field study on 13 semi-wild bachelor horses (Equus ferus przewalskii) in (a) standard social situations, and (b) when new horses joined the group (i.e. introductions). Only interventions in agonistic encounters were analysed. Eight of 13 animals directed intervention behaviour toward threatening animal in agonistic encounters of group members. One stallion was particularly active. The stallions did not intervene to support former group mates or kin and interventions were not reciprocated. In introduction situations and in standard social situations, the interveners supported animals which were lower in rank, but targeted, threatening animals of comparable social rank. After introductions, stallions received more affiliative behaviour from animals they supported and thus appeared to intervene for alliance formation. In standard social situations, interveners did not receive more affiliative behaviour from animals they supported and may primarily have intervened to promote group cohesion and to reduce social disruption within the group

Social Ecology of Horses

Horses (Equidae) are believed to formidably demonstrate the links between ecology and social organization. Their social cognitive abilities enable them to succeed in many different environments, including those provided for them by humans, or the ones domestic horses encounter when escaping from their human care takers. Living in groups takes different shapes in equids. Their aggregation and group cohesion can be explained by Hamilton`s selfish herd theory. However, when and which group to join appears to be a conscious individual decision depending on predatory pressure, intra group harassment and resource availability. The latest research concerning the social knowledge horses display in eavesdropping experiments affirm the need for an extension of pure genetic herd concepts in horses for a cognitive component. Horses obviously realize the social composition of their group and determine their own position in it. The horses` exceedingly flexible social behavior eagerly demands for explanations about the cognitive mechanisms which allow horses to determine their individual decisions

Behaviour of Horses in the “Round Pen Technique”

I investigated the behavioural background of the way horses learn to follow humans in the “round pen technique” suggested by "horse whisperers” as a gentle method for initial horse training. Though the practicability of this technique has been adequately demonstrated in the past, the horses‘ behaviour during such training has not yet been documented in detail. DIn a riding arena, horses, that did not follow the trainer immediately, were chased away so that they galloped around the trainer. Galloping horses showed specific behaviour such as turning the ear to the trainer, chewing, licking, and stretching head and throat downwards. In subsequent trials horses needed to be chased for less time and finally followed immediately, even when conditions were changed or the trainer was replaced by another person. This suggests that horses learn to follow in this particular situation and also show some generalisation. However, following did not occur on a pasture even after several successful trials in the riding arena