Behavioral and Neural Resilience to Isolation in a Eusocial Insect

Social experience early in life appears to be necessary for the development of species-typical behavior in animals ranging from insects to primates. Isolation during critical periods of maturation has been shown to impact behavior, gene expression, and brain development in vertebrate and invertebrate clades, yet remarkable resilience to social deprivation, senescence, and loss of sensory input have been demonstrated in some ant species. We reared workers of Camponotus floridanus under conditions of social isolation for increasing time periods up to 45 days and evaluated their behavioral performance, quantified brain development and biogenic amine levels, and compared results of isolated workers with control workers that had natural social contact during development. We found that brood care and foraging performance by isolated workers were unaffected by a lack of social contact. Antennal lobe volume loss occurred in ants experiencing longer isolation periods, while the size of the mushroom bodies, which function in higher-order sensory processing, increased over time after eclosion and were not different from mature controls. Titers of the neuromodulators serotonin, dopamine, and octopamine remained stable in isolated workers. Our results indicate that workers of C. floridanus are largely robust to the deprivation of social contact early in life. ### Competing Interest Statement The authors have declared no competing interest.