Eric Baccega / Siamang Gibbon (Hylobates syndactylus) vocalising, vocal pouch inflated, captive, native to forests of Malaysia, Sumatra and Thailand

Rod Williams / Golden poison dart frog (Phyllobates terribilis) with throat pouch / vocal sacs expanded. Captive occurs Colombia. Endangered species

Eric Baccega / Two Siamang Gibbons (Hylobates / Symphalangus syndactylus) calling, vocal pouches inflated, Endangered, captive, from SE Asia

Michael & Patricia Fogden / Darwin's Frog (Rhinoderma darwinii) male on forest floor with vocal sac full of young, austral Beech forest, Chiloe Island, Chile

Konrad Wothe / Siamang (Symphalangus syndactylus) vocalizing with vocal pouch inflated, native to southeast Asia