Comparison of the social systems of primates and feral horses: data from a newly established horse research site on Serra D’Arga, northern Portugal

Abstract

Horses are phylogenetically distant from primates, but considerable behavioral links exist between the two. The sociality of horses, characterized by group stability, is similar to that of primates, but different from that of many other ungulates. Although horses and primates are good models for exploring the evolution of societies in human and non-human animals, fewer studies have been conducted on the social system of horses than primates. Here, we investigated the social system of feral horses, particularly the determinant factors of single-male/multi-male group dichotomy, in light of hypotheses derived from studies of primate societies. Socioecological data from 26 groups comprising 208 feral horses on Serra D'Arga, northern Portugal suggest that these primate-based hypotheses cannot adequately explain the social system of horses. In view of the sympatric existence of multi- and single-male groups, and the frequent intergroup transfers and promiscuous mating of females with males of different groups, male-female relationships of horses appear to differ from those of polygynous primates.

Spatial positioning of individuals in a group of feral horses: a case study using drone technology

“…This region has a Mediterranean climate, and the horse habitat includes a grass field, rocky ground, a forest, and shrub areas. More than 200 feral Garrano horses live in this region (Ringhofer et al 2017). The focal group comprised one adult male (Uzumasa), seven adult females (Uji, Katsura, Gion, Fushimi, Kishiwada, Ayabe, and Akashi), and two foals born in the spring of 2016.…”

Horses and nomads in Mongolia

“…The genus Equus includes horses, zebras, and donkeys. My colleagues and I targeted horses for study in 2014 (Matsuzawa 2017;Tomonaga et al 2015;Ringhofer et al 2017), leading to field studies in Portugal, Fig. 4 The foals are tied to a long string to keep their mothers near them.…”

Horse cognition and behavior from the perspective of primatology

“…It also describes why readers of the journal Primates would do well to start considering horses in relation to the study of human and nonhuman primates. In our recent research, my colleagues and I have advanced the study of horse cognition using a computer-controlled touch panel (Tomonaga et al 2015) and also the behavioral study of wild horses, in the Serra D'Arga in Portugal (Ringhofer et al 2017). A parallel approach using both laboratory work and fieldwork is intended to provide a better understanding of horses from a holistic perspective.…”

“…The field site is now run by Satoshi Hirata and his team: Shinya Yamamoto, Monamie Ringhofer, Renata Mendonça and Sota Inoue. The first research paper on these horses came out recently in Primates (Ringhofer et al 2017).…”

“…Ringhofer et al (2017) report that there are currently 208 individuals in 26 groups at the site, and each individual horse has been identified by the research team. The follow-up study this year clearly showed two major factors.…”