Lateralization of mother-infant interactions in wild horses.

The research investigates how wild horses, specifically Przewalski’s species, display a lateralized behavior while interacting with their offspring. The study’s findings reveal that both the foals and their mothers prefer viewing each other through their left eye, indicating right-hemispheric dominance. This behavior is similar to the lateralization observed in other mammals, including humans, and suggests that lateralized behavior in social interactions may be a common trait among horses that’s not modified by domestication or certain environmental conditions.

Understanding Behavioral Lateralization

• Behavioral lateralization is the tendency of animals or humans to use one side of their body more prevalently than the other, which corresponds to brain hemispheric dominance.
• In this study, the researchers used the lateral position preferences during mare-foal reunions as a marker of visual lateralization.
• The results demonstrated that both foals and their mothers showed a preference for keeping each other in the visual field of their left eye – indicating right hemisphere brain dominance.

Lateralization in Mother-Offspring Interactions

• Mother-offspring interactions in Przewalski’s horses, a wild horse species in Mongolia, were studied to observe patterns of lateralization.
• The researchers found that in various types of foals’ behavior, there was a preference to keep the mother in the left visual field.
• It was also noted that when a mother was approaching her foal, there was a population-level left-eye bias. This suggests a right-hemisphere dominance in control of mother-offspring interactions.

Comparison with Feral Horse Foals

• The study showed that when travelling slowly, Przewalski’s foals showed a stronger preference for left eye use as compared to foals of feral horses.
• This comparison validates the finding that the right-hemispheric dominance in mother-offspring interactions is not exclusive to feral horses.

Implications of the Study

• The research indicates that lateralized behavior in horses during social interactions is not influenced by domestication or specific environmental conditions, making it a robust trait across equine populations.
• Lateralized behavior may provide the benefits of improved social processing responses to stimuli, which could be advantageous in their natural environments.