Cover legend: A male swamp sparrow singing in a marsh in central Pennsylvania. As juveniles, male swamp sparrows copy the songs of a dozen or more different tutors, only a few of which are maintained in the adult repertoire. Neural traces of tutor songs that were performed only during juvenile development persist in sensorimotor regions of the adult sparrow's brain, likely reflecting a long-lasting memory of early experience. Photography by Rob Lachlan. See the article by Prather et al. in this issue (pages 10586–10598).