Entrogression

Entrgression is a neologism used to describe the inward diffusion of external influences across internal boundaries within a system, such as a population, ecosystem, or organism. The term is not widely standardized in scholarly literature, and its precise meaning varies by author. In general, entrogression denotes processes by which genetic material, cultural traits, ecological interactions, or other inputs originating outside a defined interior boundary become integrated or entrenched inside that boundary over time.

Etymology and usage: The word combines entro- from Greek entos meaning inside with -gression from Latin grad- to step, signaling an inward progression. Because it lacks formal definition in major dictionaries, some authors reserve entrogression for theoretical discussions or speculative models rather than empirical reporting.

Concept and mechanisms: In theory, entrogression could occur through repeated back-and-forth transfer within a closed or semi-closed system, such as a metapopulation, a symbiotic association, or a cultural network. Mechanisms might include internalized genetic exchange across subpopulations, selection favoring externally derived traits that spread inward, or the embedding of exogenous interactions into core processes. It is often contrasted with introgression, which emphasizes cross-boundary exchange between distinct lineages, whereas entrogression emphasizes internal diffusion.

Relationship to related ideas: Entrogression is related to, but distinct from, introgression, horizontal gene transfer, endosymbiosis, and cultural diffusion. Its utility rests in highlighting internal pathways of influence that do not necessarily involve crossing species or major boundary barriers.

Status and reception: The term remains stylistically debated and is not part of a standardized framework. Its use is mainly in theoretical or exploratory discussions, and it should be clarified when encountered.

See also: introgression, gene flow, horizontal gene transfer, cultural diffusion, endosymbiosis.