They weigh 4-4.5 lbs. Diurnal for the part of the year in which they feed on fruit and new leaves. In the dry season, when fruit and new leaves are not available, they become nocturnal and feed on nectar. Occasionally older offspring remain with their parents for a time after puberty. On Comoros Island they live in larger unstructured groups with several males and females.
Aggressive behavior is uncommon.
Scent marking is very important sustained by rubbing branches with the crotch, forehead and hands. Unusual among primates, mongoose lemurs voluntarily share food with one another. Mating is seasonal. Mothers will allow only other mothers to grooms their infants. Fathers play no part in infant care.