4aAB1. Song displays, song dialects, and lek mating systems in hummingbirds.

Session: Thursday Morning, May 16

Time: 8:05

Author: S. L. L. Gaunt
Location: Borror Lab. Bioacoustics, Dept. Zool., Ohio State Univ., Columbus, OH 43210


Males of some hummingbirds, including Colibri (violet-ears), congregate and display from traditional areas, leks, to attract mates. Hummingbirds use a vocal display. Males on a lek share the same song, i.e., nearest neighbors share song; males on distant, acoustically isolated, leks have different songs, i.e., there are dialects. Dialects have been used as evidence for song learning in birds, and, although song learning is usually ascribed to oscines and parrots, hummingbirds share vocal organ (syrinx) structures with them consistent with song learning ability. Digital spectrogram cross correlation was used to objectively determine degree of song similarity; this statistic was used in cluster analysis to describe relationships between birds and with the Mantel method to test hypotheses about associations. Further, males of a lek deliver their song cooperatively, i.e., without interference. The resultant is a lek signal that, from a distance, sounds as one song. If, as in other cooperative lekking systems, there is a skew in benefits, i.e., few obtain mates, then other males may gain benefits indirectly through relatedness (kin selection). Results from preliminary, DNA ``fingerprinting'' do not support this hypothesis, and alternative explanations are suggested. [Work supported, in part, by NSF.]

from ASA 131st Meeting, Indianapolis, May 1996