Retraction Note: The Hidden Suitability of the Male Zebra Finch’s Courtship Song

The authors retracted this article because, on further analysis, one of the synthetic song pairs used in the female preference test (data in Fig. 3c,d) was shown to be reliable in its classification of short versus long path length only 35% of the time, and a second song pair was reliable only 75% of the time. Consequently, the authors have lost confidence in the ability to interpret these data. All authors agree with this retraction.