Number of Identified Specimens (NISP)

The number of identified specimens, universally abbreviated NISP, is the most basic quantitative measure in zooarchaeology: a simple count of every bone or bone fragment that an analyst can identify to a taxon. It is the first number computed for almost any faunal assemblage because it is fast, transparent, additive across deposits, and reproducible. Yet, as Reitz and Wing emphasize and Lyman dissects in detail, NISP is an observation count rather than an animal count, and it is distorted by fragmentation, by recovery technique, and by the fact that fragments of a single bone are not independent of one another. Understanding precisely what NISP does and does not measure is the foundation on which all other faunal abundance estimates rest.