Paik, A.; Trzeciak, J.; Harrington, C.; Steele, A.

Food anticipatory activity (FAA) is a robust behavioral output of food-entrained circadian rhythms, characterized by increased locomotor activity prior to scheduled feeding. Despite the social nature of rodents, FAA is almost exclusively studied in singly housed animals, leaving the influence of social context largely unexplored. Here, we used implanted wireless devices to measure individual locomotor activity and subcutaneous body temperature in group-housed mice and compared these measures to singly housed controls. Social housing significantly suppressed FAA in both male and female mice. In parallel, preprandial increases in body temperature were markedly attenuated in group-housed animals. These findings demonstrate that FAA is a flexible, state-dependent behavior that reflects both circadian timing and energetic demand. Together, these results identify social context as an important and underappreciated determinant of food-entrained circadian biology.