Nicaraguan Sign Language's signing community grew from a founding cohort to over five hundred members within about fifteen years

linguisticslanguage-emergencenicaraguasign-languageeducation

Two Tier-1 sources give approximate figures for the size of the Nicaraguan Sign Language (NSL) signing community as it grew from its founding cohort. They are not independent of each other — see the caveat below. Judy Kegl's organization, Nicaraguan Sign Language Projects, Inc., states that after the 1979 revolution "the special education school in Managua was re-opened, but this time with hundreds of deaf students attending academic classes at the Melania Morales Special Education Center in Barrio San Judas." Ann Senghas's 1995 MIT dissertation gives a cumulative figure for the community she was studying at time of writing, roughly a decade and a half after the schools reopened: "All together these children and young adults make up a large, vibrant community of over five hundred members (with more entering the schools every year), most of whom live in Managua, the capital city."

Neither figure is an exact headcount — "hundreds" and "over five hundred" are both approximations — but they come from the two people most directly responsible for identifying and documenting the language: the linguist who studied it and the linguist-turned-NGO-founder who built an organization around it. The two figures are consistent in order of magnitude and trajectory: rapid growth from a founding cohort into a multi-hundred-person community within roughly fifteen years.

That agreement, however, is not corroboration in the sense 00-meta/specs/sources.md requires. Independent means a different author group and a different venue, and these two sources are neither: Kegl directed the Nicaraguan Sign Language Project that Senghas joined in 1989, sat on Senghas's thesis committee, and is her co-author on the very paper the dissertation cites for its cohort history (Kegl, Senghas & Coppola, 1995). Both figures therefore rest on one research circle's fieldwork, counted twice. An enrollment figure from outside that circle — Laura Polich's archival history of the community (Gallaudet University Press, 2005), or SIL International's 2012 survey report, both flagged and unread in the originating capture — would be the first genuinely independent check on this number.

This growth curve is the demographic backdrop for the second-cohort systematization effect — Senghas's grammar findings depend on a continuously replenished younger cohort ("more entering the schools every year") large enough to constitute a genuine second generation of child learners.

Correction history.

• 2026-08-25 (cross-model audit, claude-opus-5) — Two corrections; the Senghas source was independently re-extracted and its quote confirmed verbatim. (1) The opening sentence read "Two Tier-1 sources independently give approximate figures." They do not: by sources.md's own definition, Kegl and Senghas are one author group, and the note's second paragraph already said as much ("the two people most directly responsible") without drawing the conclusion. "Independently" removed and the dependence stated outright, with the outside sources that would discharge it named. (2) The Kegl-side quote was load-bearing in the body with no pointer in frontmatter; the corroborating source's URL, sha, tier, and non-independence are now recorded in corroborating_source_* fields. The claim itself — over five hundred members by the mid-1990s — is unchanged and verbatim in Senghas 1995, p.37.