“For birds, wing waves are like flipping the bird or saying, ‘Put up your dukes. I’m ready to fight,’” said Duke biologist Rindy Anderson.

While scientists had long suspected this kind of behavior, it had been difficult to prove by seeing the birds in action.

To get closer, Anderson and an engineering student built a computer and robotic parts to install inside the body of a deceased male sparrow.

They then created a “robosparrow” that could flap its wings and sing like a real bird.

Anderson brought the robot to a sparrow nest in Pennsylvania and placed it around the live males.

Testing the birds’ reactions to the robot showed that its wing movement created the most aggressive response from the male sparrows.

The robosparrow worked so well that many of the male sparrows swooped in so aggressively they tore off the head of Anderson’s robotic bird, putting future experiments on hold. 

Video Frame: Duke University