Primates are highly social animals for whom social isolation is acutely harmful, and research and zoo standards increasingly require social housing as a welfare baseline for all primate species.
Primate social housing is a clear welfare requirement grounded in behavioral biology and extensive research evidence. Social isolation in animals evolved for complex social group living causes profound psychological harm -- documented in elevated stress indicators, stereotypies, self-injurious behavior, and impaired cognitive function. The regulatory movement toward mandatory social housing reflects scientific consensus that isolation is not an acceptable baseline for primate welfare. Implementation challenges including aggression management, disease transmission risk, and space requirements are real but navigable through species knowledge and management expertise. Social housing is a welfare minimum, not a luxury, for primate facilities.