Feather arrays are patterned by interacting signalling and cell density waves

William K. W. Ho, Lucy Freem, Debiao Zhao, Kevin J. Painter, Thomas E. Woolley, Eamonn A. Gaffney, Michael J. McGrew, Athanasia Tzika, Michel C. Milinkovitch, Pascal Schneider, Armin Drusko, Franziska Matthäus, James D. Glover, Kirsty L. Wells, Jeanette A. Johansson, Megan G. Davey, Helen M. Sang, Michael Clinton, Denis J. Headon