Why does the tree frog throat move?

The throat of a tree frog moves primarily during vocalizations, which are essential for communication, especially during mating season. Male tree frogs expand and contract their vocal sacs to amplify their calls, attracting females and asserting territory. The movement of the throat, often noticeable as a bulging or swelling, helps produce the characteristic sounds associated with different species of tree frogs. This vocal behavior is crucial for their reproduction and survival in their habitats.