在美国圣胡安岛沿海,一只黑色的小狗正在指挥一艘快艇航行。“稍微往右一点,再稍微往左一点。”金发女郎伊丽莎白·西利一边观察小狗的耳朵,一边对舵手下达指令。没过多久,船员就看到一团棕黄色的物体在蓝色的海面上下沉浮。这正是他们要寻找的东西——虎鲸的粪便。借助一个前端套着塑料杯的长杆,工作人员小心翼翼地捞起这堆排泄物,并迅速进行冰冻保存。通过分析粪便的DNA,科研人 On the coast of San Juan, USA, a black puppy is directing a speedboat sailing. “Move a bit a little to the left, and a little further to the left. ” Blonde Elisabeth Silly observes the puppy’s ears and orders the helmsman. It did not take long before the crew saw a cloud of brownish objects floating down the blue sea. This is exactly what they are looking for - killer whales’ excrement. With a pole lined with plastic cups on the front, the staff carefully picked up the pile of excrement and quickly frozen it. By analyzing faecal DNA, researchers