User blog comment:Tinni/The Espada rank thing/@comment-1454424-20091129051727

Good point, Rapster278. Here is something else to mull over, Lilynette said Arrancar do not age. However, Shinigami do. We have seen Hisagi, Nanao, Matsumoto and Ichimaru grow from children to adults in the 100 year. Yachiru too will one day grow-up (or not). Yamamoto was once young, or so it is implied. However, Lilynette words implied that she would never grow old, never grow-up. Makes sense, with Hollows it seems more an evolution over time. So perhaps Barragan's respira wasn't as effective in ageing arrancars as it is in ageing Shinigami.