Rozmrech

Rozmrech is a term used in speculative biology and some science-fiction contexts to denote a reversible developmental program that lets an organism alternate between two distinct life forms in response to environmental conditions. The term is a neologism with unclear origin, often attributed to worldbuilding authors rather than established biology. In the commonly cited framework, rozmrech organisms exhibit a binary life cycle: a sessile, resource-acquiring form and a mobile, dispersive form. The transition is governed by a gene network and epigenetic changes triggered by cues such as temperature, nutrient levels, and crowding. Morphological and metabolic reprogramming accompanies the switch, enabling the organism to optimize for growth under stable conditions or dispersal when conditions deteriorate.

Ecologically, rozmrech dynamics can affect population spread, habitat colonization, and interspecific interactions by introducing alternating life-history phases. In fiction and game settings, rozmrech is often used to explain rapid range expansion or episodic outbreaks without invoking external introductions.

In real biology, there is no established concept named rozmrech; it remains a fictional construct used in literature and games. See also metamorphosis, phenotypic plasticity, life cycle.