Why do so many birds have spots and dots on their feathers?This episode explores a fascinating idea: birds may already be wired to like certain visual patterns long before those patterns appear on feathers.
Researchers studied estrildid finches, a family of small seed-eating birds found around the world. About a quarter of these species have white dot patterns on their plumage, often shared by both males and females. The big question was whether these dots evolved because birds already found them visually appealing.
To test this, scientists showed 12 different finch species simple printed patterns—white dots and white stripes—and measured how often birds looked at each one in a window bird feeder. Looking time is a common way to measure attention and preference. The results were clear: most species spent more time looking at white dots than stripes, especially when they were hungry (see Figure 2 on page 5).
In other words, birds might not have evolved dots to attract attention—dots may have evolved because birds were already paying attention to them.
