Peacocks, when fanning their feathers to attract females, shake the feathers, creating an inaudible sound for humans but one that female hens can hear, even from far away. In the video, scholars explore evolution by analyzing artificial selection first, specifically looking at dogs. The instructor then moves into natural selection, focusing on Peter and Rosemary Grant's studies on birds on Daphne Major in the Galapagos Islands to discuss directional selection. Viewers analyze Darwin's finches, stabilizing selection, and the video finishes by looking at sexual selection using the peacock as an example.