Heritable differences in synaptic zinc-transporter levels drive variation in learned birdsong

The authors have withdrawn this manuscript. During revision of our manuscript, we carried out several lines of additional experiments and analyses that failed to fully support and reproduce the results previously presented in Figure 4 (regarding potential mechanisms whereby zinc and SLC39all contribute to song tempo). We therefore do not want this result to be cited and are withdrawing our paper while we carry out additional experiments to clarify potential contributions of SLC39all to individual variation in song tempo. We apologize for any inconvenience caused to our readers. Any questions can be addressed to DGM (first/corresponding author) and/or MSB (last/senior author).