The main objective of this article is to outline an account of the evolution of the analytic (Free State) type of possessive noun phrases in Spanish Arabic and the loss of the synthetic (Construct State) type in Shamaliya Arabic, two relatively unknown varieties that are historically related. Possessive noun phrases can vary at the level of Syntax, PF or the Lexicon. Variation at the level of Syntax yields the distinction between the synthetic type and the analytic type. These have the same underlying structure but different derivations determined by the values of an EPP feature associated with Num, the DP-equivalent of clausal T. When Num has the [+EPP] value, it triggers subject-raising of the possessor to Spec, Num leading to the derivation of the synthetic type. When Num has the [−EPP] value, the possessor remains in-situ and consequently triggers the appearance of the genitive preposition. The evolution of the analytic type involves the acquisition of the [−EPP] value and the loss of the synthetic type the loss of the [+EPP] value. Variation at PF involves deletion or not of the definiteness feature/article of the head noun or the possessor in the synthetic type, which yields three logical patterns: [N the-N], [the-N N] and [the-N the-N]. Spanish Arabic had all three patterns, while Moroccan Arabic and other varieties have only the first pattern. Finally, variation at the level of the Lexicon accounts for differences relating to which preposition is used in possessive noun phrases. The Maghreb/Western varieties make use of the genitive preposition, while the Mashreq/Eastern varieties tend to make use of the dative preposition instead.