Fig. 1.

Hummingbird tongues. (A) Nectarivores use their tongue (yellow) as their primary food-gathering tool. (B) Lateral picture of a post mortem Ruby-throated Hummingbird (Archilochus colubris) tongue tip protruding from the bill tip. (C) Dorsal view of the morphology of a hummingbird tongue (approximate dimensions for A. colubris) showing length of the entire tongue, open-sided grooves, and the fringed (lamellar) region of the tip (distal approximately 6 mm). Base of the tongue is on the left; tip on the right. (D) Cross-sectioning shows the structural arrangement along the distal region of the tongue; green arrows identify the placement of the cross-sections. Black lines indicate the same structures in dorsal and cross-sectional views. Note the change in position of supporting rods from the base of the grooves to the tongue tip. Unlabeled scale bars, 0.5 mm.