Movie 3.

Edited footage of a hummingbird drinking nectar in dorsal view. High-speed video (500 fps) of a Rufous-tailed hummingbird (Amazilia tzacatl), the nectar reservoir is located on the left. First, the video was subject to monotonic enhancements in brilliance, contrast, and chroma, seeking to improve visualization of the tongue base. Second, the video is played back at different speeds in order to facilitate visual tracking of the tongue base and its interaction with the fluid inside the oral cavity. Third, we present an animated superimposition of mechanics data including shapes and shades obtained from the bill and tongue motion analyses (Fig. S2). Red line in the middle of the bill represents the tongue, and the V shape crossing the red line represents the tongue wings at its base. Blue shadow inside the bill depicts the nectar flowing intraorally. Green double-headed arrow on the left symbolizes the dorso-ventral separation of the bill tips, and yellow double-headed arrow on the right denotes the dorso-ventral separation of between maxilla and mandible at the bill base. Note that two licks are required to move a single aliquot of nectar from the nectar chamber to the throat.