Using this Phoenician letter for just a vowel seem is because of the early Greek alphabets, which adopted the letter "omicron" to symbolize the vowel /o/. The letter was adopted with the value inside the Previous Italic alphabets, including the early Latin alphabet. Spotify is unavailable on this browser. https://daltonmvbfi.tkzblog.com/36836123/facts-about-o-sapinho-e-a-borboleta-revealed