Bower building. Bower building. (A) Characteristic behavioral patterns associated with pit digging (Upper) and castle bower building (Lower). (B) Average locations of scoops (gray) and spits (red) during bower-building trials in the pit-digging species C. virginalis and the castle-building species M. conophoros. Consensus locations of the bowers are indicated by dashed black circles. (C) Results of a Student’s t test (two-tailed, P = 0.006) comparing difference score (in millimeters; mm) between C. virginalis (pit digging; yellow) and M. conophoros (castle building; green). (**P < 0.01.) (D) Maximum-likelihood phylogeny from genome-wide variants of the species sequenced in this study. Numbers at nodes are bootstrap support values. Ryan A. York et al. PNAS 2018;115:47:E11081-E11090 ©2018 by National Academy of Sciences