What this means for learners
Bakairí and Yao share 18 sounds — roughly 37% of Yao's inventory overlaps with Bakairí. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 31 sounds found only in Yao represent the greatest pronunciation challenge for Bakairí speakers. The adult brain tends to map unfamiliar sounds onto the closest native equivalent — a process that produces the characteristic "accent" of a second-language speaker. Learning to hear and produce these sounds as distinct requires focused ear training, not just repetition.
Conversely, Bakairí has 12 sounds not used in Yao. Native Yao speakers learning Bakairí will face the mirror-image challenge with these sounds.
Phoneme inventories from PHOIBLE. Data reflects one documented inventory per language; some variation exists across dialects and sources.