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The nesting activity, life cycle, and brood ball morphometry of the dung beetle Oniticellus cinctus (Fabricius, 1775) (Coleoptera: Scarabaeidae) were studied under laboratory conditions for the first time in India. The females made a brood chamber within the dung mass provided, wherein they made brood balls to lay eggs. The life cycle includes egg, larva (three instars), pupa, and adult stages. The total duration for the development was about one month. The study found that there was a significant difference present in the brood ball diameter (except in the first and second instars) and brood ball weight (except in the second instar and pupa) of the six life cycle stages. It was also found that brood ball weight and diameter have a significant positive correlation as well as a linear relationship.

In Oniticellus cinctus (F.) the nest chambers each contain about twenty brood balls. Females enlarge the brood balls during the egg and larval stages and remain in the chamber for the whole period of brood development (1 month); they then make a new nest after 1 week. The presence of the brood releases parental care and ensures that the mother remains in the nest: she repairs defects in the brood balls and the nest, and expels other O. cinctus females. A new ball is formed around a naked O. cinctus larva, but larvae of other species are killed. In addition, the brood inhibits oviposition: removal (or addition) of brood balls stimulates (or inhibits) egg laying. In inhibited ovarioles, existing follicles are resorbed and production of new ones ceases. Control of clutch size by the brood is an adaptation to the nest structure and life history of O. cinctus. It may have an important role in the reproductive strategy of other insects with parental care.