Target animacy influences gorilla handedness.

Area of Science:

• Primate behavior
• Neuroscience
• Ethology

Background:

• Understanding lateralization in non-human primates provides insights into the evolution of brain asymmetry.
• Western lowland gorillas (Gorilla gorilla gorilla) offer a unique model for studying complex social behaviors and motor skills.

Purpose of the Study:

• To investigate the relationship between handedness and the nature of the target object in western lowland gorillas.
• To explore how target animacy influences unimanual action lateralization in a social context.

Main Methods:

• Dual, synchronized video observations of naturalistic behaviors in a family group of twelve gorillas.
• Systematic assessment of unimanual action lateralization (left vs. right) and target type (animate vs. inanimate).

Main Results:

• A significant interaction was found between lateralized unimanual actions and target animacy.
• Gorillas exhibited a distinct right-hand bias for actions directed toward inanimate targets.
• A correlation was observed between handedness and the animate quality of the target object.

Conclusions:

• Motor preferences in gorillas are influenced by the characteristics of the target object.
• Lateralized motor preferences may reflect differential hemispheric processing of emotive (animate) versus functional (inanimate) information.
• This study contributes to understanding the neurobiological underpinnings of handedness and its ecological relevance in primates.