I remember reading a study where researchers realized that female birds of a certain species preferred males with a darker breast. So they created what they literally called a “Super-Sexy Male” by catching a male and coloring his chest with a marker. They then ran dna tests on the eggs in the area.
Previously when the researchers had run these tests, they found a certain amount of infidelity was common for these birds. Somewhere around 10% of eggs were fathered by males who were not the primary mates of females.
After the advent of the Super Sexy Male, however, stuff got crazy in bird world. Infidelity skyrocketed, with upwards of 25% of ALL EGGS in the area being fathered by this specific male. Furthermore, his mate’s eggs were 100% his.
This is just insane to me. Just imagine you’re living your bird life when suddenly somebody scribbles on Dave’s chest and the ladies can’t stop throwing themselves at them. It’s stupid that we theoretically can wreck this kind of havoc on an ecosystem.