Question

In the early twentieth century, the discovery of manuscripts in the Tarim Basin written in Tocharian—an extinct Indo-European language family—upended long-held assumptions regarding the geographical dispersion of ancient Indo-European dialects. Prior to these excavations, philologists generally adhered to the 'centum-satem' dichotomy, a taxonomic scheme that divided Indo-European languages into western ('centum') and eastern ('satem') branches based on the phonetic development of palatal consonants. Standard models postulated that centum features were strictly confined to European branches such as Celtic, Germanic, and Italic, whereas satem developments characterized Asiatic branches including Indo-Iranian and Baltic. Tocharian, however, situated in the easternmost periphery of the Indo-European sphere in Xinjiang, unexpectedly exhibited unambiguous centum characteristics, retaining velar stops rather than assibilating them into sibilants.

This anomaly forced historical linguists to reevaluate the chronological and spatial dynamics of early Indo-European migrations. Rather than representing an isolated anomaly, Tocharian was increasingly interpreted as an archaic offshoot that had diverged prior to the widespread areal diffusion of satem innovations across Eurasia. Consequently, scholars ceased treating the centum-satem split as a primordial phylogenetic division, recognizing instead that satem features emerged through subsequent regional wave developments that bypassed isolated peripheral dialects like Tocharian.

Based on the passage, which of the following can be inferred regarding the 'centum-satem' dichotomy prior to the discovery of Tocharian manuscripts?

Select all that apply.