Eusociality is the highest level of organization of sociality. It is defined by the following characteristics: cooperative brood care, overlapping generations within a colony of adults, and a division of labor into reproductive and non-reproductive groups. The division of labor creates specialized behavioral groups within an animal society which are sometimes referred to as 'castes'. Eusociality is distinguished from all other social systems because individuals of at least one caste usually lose the ability to perform behaviors characteristic of individuals in another caste. Eusocial colonies can be viewed as superorganisms.
Co-operative brood rearing, seen here in honeybees, is a condition of eusociality.
Suzanne Batra introduced the term "eusocial" after studying nesting in Halictid bees including Halictus latisignatus, pictured.
Weaver ants, here collaborating to pull nest leaves together, can be considered eusocial, as they have a permanent division of labor.
Swarming Iridomyrmex purpureus ants. The young queens are black, winged, and much larger than the wingless workers.
Sociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies.
Herd of American bison at Genesee Park
The mouse lemur is a nocturnal, solitary-but-social lemur native to Madagascar.
Giant honey bees cover the honeycomb of their nest.
