Equine Social Structure
equine
Kathie Gregory examines the two groups of social organization found in Equidae, including
E
group structure, dynamics and relationships, and debates whether hierarchies within
groups actually exist
quidae have evolved into two groups of social organization over time. One group consists of Grevy's zebra (E Grevyi) and wild asses (E africanus, E hemionus); the other consists of the horse (Equus ferus), plains zebra (Equus quagga), and mountain zebra (Equus zebra). In terms of relationships, Grevy's zebra and wild asses tend to live alone amongst each other. Personal bonds between animals generally do not exist, other than between a mare and her foal. These species may or may not be in groups. Groups consist of different sizes and are made up of different ages and sex. They are variable and changes to the group may happen every few hours. Male stallions can have extremely large territories. Territorial boundaries are marked by dung piles to identify the territory, rather than to warn intruders. A stallion’s territory is a mating territory, so stallions are generally tolerant of other stallions in their territory. Disputes and fights are over females in estrus, typically when the female is near to boundary lines, and the fighting is between neighboring stallions. Once she has made a decision to walk into a territory the stallions stop fighting, with the resident of the territory following the mare, and the other stallion remaining at the boundary line. These species split up for part of the year, coming together for the mating season. The horse, plains zebra and mountain zebra, meanwhile, form permanent family groups, with less permanent stallion, bachelor, and peer groups. Young leave family groups at defined ages. There are no established territories, and movement is seasonal with the group relocating together. These species do not live in changeable temporary groups, neither are there solitary territorial males (Berger, 1977). Observations of feral and free range horses consistently show they belong to the group of social organization that form permanent groups. There are many preconceptions and myths around how horses naturally live, dating back to equine studies from the 1960s. Observations were accurate. However, there were, and still are, even in modern studies, incorrect interpretations of information. Firstly, in the 1960s, the human perception of animals was narrower and distinct in that their behavior was considered to be either dominant or submissive. This resulted in observational studies being written from that perspective rather than as a purely factual account. It is human nature to explain why things happen, and thus the popular viewpoint of dominance and submission was applied to what was observed. This led to the general public's perceived understanding of equine behavior. Some still believe dominance theory today, and studies, blogs, books etc., will be written from that perspective. Scientists have long tried to establish clear hierarchies when observing groups of horses and other animals. Thus, any interaction between two horses may be interpreted as one being dominant, the other submissive, and dominance hierarchies emerge as
Š Can Stock Photo/haak78
Scientists have long tried to establish clear hierarchies when observing groups of horses and other animals, yet studies often report that disagreements between horses in a social group are low key, with individuals being tolerant of each other
a theory. However, this simple, tidy explanation for what is a very complex social structure is incorrect. Any group needs cohesion and give and take in order to function effectively, and the lack of understanding of what was being observed led to this incorrect interpretation. As far back as the 1970s, there were those who found problems with this theory (Kiley-Worthington, 1977; Syme & Syme, 1979), but they were largely ignored, and the neat, easily measured dominance hierarchies informed the majority of observational reports. A further issue is that the definition of the terms, dominance and submission, is not clear or definitive. Rather, it is open to the individual interpretation of the researcher. Some define dominant as having greater reproductive success, a higher ranking, or priority access to food and water. There is no evidence to support these types of dominance and many studies have shown that these perceived goals horses are claimed to vie for simply do not exist. Time and time again, researchers report that there is no clear correlation between these supposed issues and dominance.
Environment and Habitat
Data is also dependent on what is being studied. Ethology is the study of species in their natural environment, but some studies have not adhered to this standard. Many studied equine groups that were not natural. Human intervention meant that the sex, age, and numbers within the groups were not what would be seen BARKS from the Guild/September 2018
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