1、The scientists observed the zugunruhe in the birds as they prepared for their long migration journey.
科学家们观察到了候鸟在准备进行长途迁徙之前的不安状态。
2、The phenomenon of zugunruhe is believed to be triggered by hormonal changes in the birds' bodies.
据信,zugunruhe现象是由鸟类体内激素变化引起的。