Apareguts

Apareguts is a fictional term used in science fiction and speculative biology to describe a class of microscopic gut residents that influence host physiology through signaling rather than by direct digestion. In this imagined model, aparaguts reside in the gastrointestinal tract as a cooperative consortium with the host and other microbiota, secreting neuroactive and metabolic signaling molecules that interact with the enteric nervous system and bodily tissues.

Characteristics commonly attributed to aparaguts include small size relative to other gut microbes, close association with mucosal surfaces, and rapid, bidirectional communication with host cells. They are typically depicted as mutualists rather than pathogens, gaining shelter and nutrients from the host while modulating digestion timing, appetite, stress responses, and energy balance through signaling networks. In some portrayals, aparaguts can alter the host’s metabolic state in response to diet or environmental cues, without directly metabolizing food themselves.

Origins and usage in fiction:

The term is often traced to speculative fiction writers and world-building guides as a conceptual tool to examine ethics, feasibility, and consequences of engineering gut ecosystems. In narratives and thought experiments, aparaguts may be transmitted through ingestion of certain materials or acquired via social contact, and may be depicted as susceptible to external signals or designer controls, raising questions about autonomy and biotechnological manipulation.

Related topics:

Symbiosis, microbiome, gut-brain axis, and synthetic biology.