Sometimes these families are grouped in loose communities of up to 30 animals. The animals keep in touch while travelling through the forest, and come together when a fruiting tree is found. Neighbouring groups call to each other through the forest with raucous calls. They have an elaborate system of alarm calls which alert group members to danger. Red ruffed lemurs produce litters of offspring and can have up to six infants at one time, but more usually twins are produced. They are also unusual in that they do not carry their young on their stomachs or backs but instead leave their babies in a nest of leaves whilst they go off to find food alone.