Abstract: An individual's positive or negative perspective when judging an ambiguous stimulus (cognitive bias) can be helpful when assessing animal welfare. Emotionality, as expressed in approach or withdrawal behaviour, is linked to brain asymmetry. The predisposition to process information in the left or right brain hemisphere is displayed in motor laterality. The quality of the information being processed is indicated by the sensory laterality. Consequently, it would be quicker and more repeatable to use motor or sensory laterality to evaluate cognitive bias than to perform the conventional judgment bias test. Therefore, the relationship between cognitive bias and motor or sensory laterality was tested. The horses (n = 17) were trained in a discrimination task involving a box that was placed in either a “positive” or “negative” location. To test for cognitive bias, the box was then placed in the middle, between the trained positive and negative location, in an ambiguous location, and the latency to approach the box was evaluated. Results indicated that horses that were more likely to use the right forelimb when moving off from a standing position were more likely to approach the ambiguous box with a shorter latency (generalized linear mixed model, p < 0.01), and therefore displayed a positive cognitive bias (optimistic).

Abstract: Animals that live in stable social groups need to gather information on their own relative position in the group`s social hierarchy, either by directly threatening or challenging others, or in a less costly manner, by observing interactions among others. Such indirect inference of dominance relationships has previously been reported from primates, rats, and birds and fish. Here, we show that domestic horses, Equus caballus, are similarly capable of social cognition. Taking advantage of a specific “following behavior” that horses show towards humans in a riding arena, we investigated whether bystander horses adjust their response to an experimenter according to the observed interaction and their own dominance relationship with the horse whose reaction to the experimenter they had observed before. Horses copied the following behavior towards an experimenter after watching a dominant horse following, but did not follow after observing a subordinate horse or a horse from another social group doing so. The following behavior which horses show towards an experimenter therefore appears to be affected by the demonstrator`s behavior and social status relative to the observer.

Abstract: Darwin’s claim of differences in mental abilities between man and other animals is a matter of degree rather than of kind and appears to apply nicely to a comparison of choice behaviour in humans and equine. Humans and horses make two kinds of decisions, fast reflexive decisions based on heuristics, and slower more considered decisions that require more complex cognitive processing. Heuristic use is adaptive in that decisions based on them are most often useful in helping an organism to survive while requiring little time and cognitive effort. There is considerable evidence that there is an innate basis to many heuristics in humans as well as horses. A case will be made that the investigation of heuristics specific to horses will lead to an understanding of equine behaviour that has not been possible using traditional learning theories alone. Traditional learning theories are restricted in explaining behaviour to appeals to reinforcement regimes or to the formation of associations between novel stimuli and stimuli that cause innate reflexes, but they are of no use when behaviour is controlled by stimuli that have never been reinforced or been systematically paired with other stimuli that cause reflexive responses. For example, a horse in a two-choice discrimination task may choose a familiar stimulus which has never been reinforced over a new stimulus added to the discrimination task, simply due to the use of an heuristic that usually works -- when in doubt, choose a more familiar object over an unfamiliar one. Conflict resolution strategies provide another good example of heuristic vs. slow decision making. In both humans and horses, conflict resolution strategies are used within, but not typically between social groups. Such groups can be defined as community of interest. Depending on the resource that has to be defended, groups may well be small identities, such as human families or horse harems, or large aggregations such as herds in horses, or religious groups or nations in humans. Fast and simple resolution is possible with stable social identities in simple environments, but more complicated and time consuming deliberative processes are required to resolve conflict over long-term resource acquisition, for decisions in complex conflicts situations and complex social settings.

Abstract: 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.

Abstract: Domesticated horses are constantly confronted with novel tasks. A recent study on anecdotal data indicates that some are innovative in dealing with such tasks. However, innovative behavior in horses has not previously been investigated under experimental conditions. In this study, we investigated whether 16 horses found an innovative solution when confronted with a novel feeder. Moreover, we investigated whether innovative behavior in horses may be affected by individual aspects such as: age, sex, size, motor and sensory laterality, fecal stress hormone concentrations (GCMs), and task-related behavior. Our study revealed evidence for 25% of the horses being capable of innovative problem solving for operating a novel feeder. Innovative horses of the present study were active, tenacious, and may be considered to have a higher inhibitory control, which was revealed by their task related behavior. Furthermore, they appeared to be emotional, reflected by high baseline GCM concentrations and a left sensory and motor laterality. These findings may contribute to the understanding of horses&#65533; cognitive capacities to deal with their environment and calls for enriched environments in sports and leisure horse management.