Universal 1648:

Original: The great majority of pronominalization strategies, regardless of language type, favour dependent-marking pattern.
Standardized: IF relative clause formation involves pronominalization, THEN it will be of dependent-marking type.
Keywords: head-marking, dependent-marking, relative clause, pronoun
Domain: inflection, syntax
Type: implication
Status: achronic
Quality: statistical
Basis: Abkhaz, Adyghe (both NW Caucasian), Arabic (Semitic), Bantu family, Basque, Burushaski (both isolate), Chechen (N. Caucasian), Dyirbal (Pama-Nyungan), Hopi (Uto-Aztecan), Hurrian (isolate), Japanese (Japanese-Ryukyuan), Kaititj (Arandic), Lakhota (Siouan), Mayan family, Navajo (Athabaskan), NE Caucasian, Quechuan family, Tewa (Tanoan), Tonkawa (Coahuiltecan), Tungusic family, Turkic family, Uralic (eastern & western), Uto-Aztecan, Washo (Hokan), Yuman family
Source: Nichols 1984: 533

Counterexamples: Tanoan family uses head-marked relativization by pronominalization. A number of older Indo-European languages exhibit occasional instances of head-marking pronominalization (Nichols 1984: 533).

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