摘要: Studies of the white-crowned sparrow, Zonotrichia leucophrys, have been instrumental in advancing understanding song learning and hormonal control reproduction birds. This article focuses on issues related to its consequences. Marler’s classic experiments this species demonstrated that exposure adult models is necessary for normal vocal development occur. They also raised possibility learning, culturally inherited dialects, may restrict gene flow among dialects possibly influence speciation process. Several controversial aspects these results are discussed.