“Bats are blind.”

The widespread belief that bats are blind is a common misconception, often perpetuated by the idiom "blind as a bat." This saying likely originated from observations of bats' erratic flight patterns in daylight, which might suggest poor vision. However, the truth is far more nuanced, and bats are certainly not blind.

Scientifically, all bats can see, though the acuity of their vision varies significantly between species. While many people associate bats primarily with echolocation—a sophisticated biological sonar system they use to navigate and hunt in darkness—this doesn't mean their eyes are useless. Microbats, which are the most common type of bat and rely heavily on echolocation, still possess functional eyes and can use their vision, especially in dim light. Megabats, often called fruit bats or flying foxes, have excellent eyesight and depend on it much more than echolocation to find food and navigate, particularly at dusk and dawn. Some species of bats even have better night vision than humans.

The persistence of this myth can be attributed to several factors. The strong association of bats with nighttime activity and their incredible ability to echolocate might lead people to assume their eyes are redundant. Furthermore, the idiom itself is so deeply ingrained in language that it reinforces the misconception, making it difficult to challenge without understanding the underlying biology. Ultimately, while their methods of perception are highly specialized for their nocturnal lifestyles, bats are far from sightless creatures.