passagingia

Passagingia is a term used primarily in speculative biology and science fiction discourse to denote the hypothetical ability of a lineage, trait, or system to persist and preserve functional integrity through successive passages across different hosts, environments, or media. The word combines passus (passage) with -gia, a suffix used in some theoretical vocabularies to denote a state or condition. It is not a recognized phenomenon in mainstream biology.

In models that employ passagingia, traits are thought to undergo selection not only within a single host but across a chain of hosts or environments, creating a conserved core and variable peripheries. Mechanisms proposed include genetic or epigenetic memory, modular gene networks, and ecological feedbacks that favor robust modules. The concept emphasizes continuity of function rather than identity of form.

In worldbuilding, passagingia helps explain how organisms or ideas survive changing conditions; in theoretical discussions, it serves as a framework to explore resilience, drift, and transmission across media. It can also appear in debates about disease reservoirs, where a pathogen might maintain essential traits through repeated host passages in a population.

Because the term lacks empirical grounding, it is treated as a speculative construct. Critics caution against conflating passagingia with established processes such as horizontal gene transfer, clonal selection, or cultural transmission, each with distinct mechanisms and evidence.

Related concepts include horizontal gene transfer, pathogen evolution, cultural transmission, and memory in biology.