Eusocial is an adjective that describes a particular type of social organization observed in certain animal species, particularly insects. It refers to a highly advanced level of social behavior, where individuals within a society, typically in a colony or a hive, exhibit distinct divisions of labor, cooperative brood care, and overlapping generations.
Eusociality is characterized by the presence of distinct castes or classes within the society, with each caste serving a specific purpose. For example, in ant colonies, the queen is responsible for reproduction, while the workers carry out tasks such as foraging, nest building, and caring for the young. These castes are usually determined by the individual's genetic makeup or specific environmental conditions.
One key feature of eusocial species is cooperative brood care, where individuals selflessly care for the offspring of other members within the society. This behavior is not observed in all social species and represents a significant level of altruism and cooperation.
Eusocial societies often have overlapping generations, where offspring stay within the society and help raise subsequent generations. This arrangement ensures the longevity and continuity of the society by maintaining a collective effort towards survival and reproduction.
Eusociality is considered a highly evolved form of social behavior and is commonly found in several insect species such as ants, bees, and termites. However, it is relatively rare in the animal kingdom as a whole. Eusocial species have garnered significant interest from researchers due to the complex social systems they exhibit, making them a fascinating subject of study in the field of sociobiology.
The word "eusocial" was coined by biologist Edward O. Wilson in the 1970s. It is derived from two Greek roots: "eu" meaning "good" or "true", and "social" meaning "relating to society or living in organized communities". The term was specifically created to describe a type of social organization observed in certain insect species, where individuals within a colony exhibit division of labor, cooperative care of offspring, and overlapping generations.