Bird wings are more than just flying instruments. They also help a bird maintain balance, mate, and threaten its enemies. Davi has just up-righted himself and this shot caught the split second instant of Davi gaining his balance.

You have a good view of Davi's clavicular air sac's here. Air sacs are a unique feature to birds. Most birds have four paired air sacs plus a single unpaired sac for a total of nine. The air sacs are membranous and thin walled (only a few cells thick), and perform several functions including; acting as air reservoirs by holding and expelling air, controlling body heat (through evaporation cooling), moistening air, cushioning the subcutaneous body layer, providing buoyancy in water birds, aiding some birds with vocalization and assisting courtship displays.

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