Brooding

Definition

Parental behavior in which an adult guards, incubates, or carries eggs or developing offspring, often at the cost of reduced feeding, mobility, or other normal activities. In arthropods, brooding takes diverse forms: external egg masses guarded by female earwigs or burying beetles; eggs carried on the body (operculum brooding in some aquatic bugs, abdominal brooding in scorpions); eggs retained within the female until hatching (ovoviviparity in many cockroaches and some spiders); or young carried after hatching (scorpion young on the mother's back). Brooding increases offspring survival by protecting against predation, desiccation, and fungal infection, and often involves active grooming or cleaning of eggs.

Etymology

From Middle English 'brood' (offspring, hatch) + '-ing' (action or process); originally avian terminology extended to other animals.

Example

Female giant water bugs (Belostomatidae) deposit eggs on the male's dorsum, who then broods them, aerating them with hindleg movements until they hatch—a reversal of the more common female brooding pattern.

Synonyms

• egg-guarding
• parental incubation
• maternal care (when female-specific)

Related Terms

• Parental investment
• ovoviviparity
• viviparity
• egg sac
• subsociality
• Phoresy
• parturition
• oviposition

Usage Notes

Distinguish 'brooding' (active parental attendance) from mere 'egg retention' in oviducts without care, and from 'internal development' in species where eggs are simply held passively. Some authors reserve 'brooding' for behaviors with observable guarding or maintenance, while others use it broadly for any egg-carrying. In arachnology, 'brooding' typically implies the female remains with the egg sac; 'egg-sac carrying' without attendance is sometimes distinguished as a lesser form of care. The term is occasionally applied to male care (as in giant water bugs, some assassin bugs, and pipefish), though historically connoted female behavior.