While horses might not be on Facebook just yet, they do have their own kind of “social network,” says one French equine behavior researcher. The resulting relationships are solidly structured and highly dependent on the particular characteristics of the individuals in the group.

Dominant horses, for example, are typically older, larger, and less fearful than other horses in the group, said Mathilde Valenchon, PhD, of the Ecology, Physiology and Ethology Department at the French National Centre for Scientific Research, in Strasbourg, France.

But “central” horses—those that tend to create multiple “friendly” relationships within the herd—tend to be (perhaps obviously) more gregarious and sociable, she said.

“Our studies on different groups of horses in seminatural conditions indicate that personality differences do matter in developing the structure of a group,” Valenchon said. She presented her findings at the 2015 French Equine Ethology Day held April 9 in Saumur.

What’s more, they determined that central individuals are not necessarily the dominant ones, such as in other mammalian groups like elephants and primates, she said.

In their most recent study, Valenchon and her colleagues observed social behavior in two groups of six mares housed in open pastures. The team tested each of the mares using the Lansade temperament test to determine specifics about their personalities. They also graded each horse’s social attitude according to detailed questionnaires completed