Post-nasal Fortition
The Spanish voiced stops/fricatives b d y g are strengthened to stops initially, but also after nasals. Such post-nasal fortition is very common in Bantu languages. For example, Swahili l and r become d after a nasal prefix, and w becomes b; voiceless stops become aspirated. In Shambala, l and r become d, and h and gh become p and g as well. In Bukusu, v and w become b, y becomes j, and l, r become d. In other languages, voiceless fricatives f, s, hl become affricates pf, ts, tl; see for example Xhosa. This is similar to the epenthetic stop in words like dance in many dialects of English, which effectively is fortition of fricative to affricate .
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