They tested different toe arrangements of peregrines and parrotlets to see if one was better suited to perching.

他们测试了游隼和鹦鹉的不同脚趾排列方式，看看哪一种更适合栖息。

Scientists drew on the anatomy and flight data of peregrines and parrotlets to model bird landings, accounting for variables such as the angle and distance to an object.

科学家利用游隼和鹦鹉的解剖结构和飞行数据来模拟鸟类着陆，并考虑到物体的角度和距离等变量。