Bats are not rodents

Bats are not rodents. They are not blind as a bat. And most do not suck blood. They are the only mammals that can fly, and with more than 1,100 species of bats, they are the most diverse type of mammal after rodents. Bats first evolved more than 50 million years ago.

Contrary to a popular misconception, most bats can see quite well, but most species also possess an extremely powerful sonarlike ability -- emitting high-pitched pulses of sound and triangulating the echoes bouncing back to their oversize ears. That allows them to swoop down and snatch food like insects out of the air in the pitch dark.
Not all bats have this ability. Most of the bats of the type known as Old World fruit bats rely instead on smell and the keen vision of their oversized eyes. The fruit bats also have a more vegetarian diet, eating fruit, nectar and pollen.

Since 2007, researchers have been investigating the deaths of thousands of bats in several dozen caves and mines in upstate New York where bats hibernate for the winter. Other bats in the same caves were found to be severely underweight. Some have white fungus on their noses, some have pneumonia, but these appear to be secondary symptoms. Researchers have not yet determined whether what they call "White Nose Syndrome" is caused by a toxin, a virus, a bacteria, or environmental factors such as pesticide use or lack of food sources.