Resum: |
In Element-Theory and similar approaches to the internal structure of segments, it is often assumed that the aperture element |A| is more sonorous and different in kind from the coloring elements |I| and |U| (Hulst 2015; Pöchtrager 2006; Schane 1984), while the latter are usually considered to be equally sonorous and display symmetrical behavior. As it has been previously noted, though, this formulation misses a recurrent crosslinguistic asymmetry. |I| and |U| do in fact have distinct behaviors (Carvalho & Klein 1996; Nevins 2012; Veloso 2013; Pimenta 2019; Pöchtrager 2015), and while typologically, rounding can be absent from a language inventory, "no language has been found that lacks both a front vowel and palatal glide" (Hyman 2008: 100 n. 11). As will be shown, this asymmetry is the source of several phenomena in Portuguese phonology, both synchronic and diachronic. Special attention will be given to nasal vowel diphthongization in non-standard European Portuguese, which reveals a preference for the front offglide over the back offglide, [j] appearing even in some contexts where [w] would be expected. This preference, as will be argued, has its origin in sonority asymmetry, |I| being less sonorous than |U|. |