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Quest Magazine, Fall 2016.

With Halloween just around the corner, bats are everywhere from decorations to horror movies. Most people think of them as aggressive and horrific creatures, but not Gary McCracken, professor of evolutionary ecology in the Department of Ecology and Evolutionary Biology in UT’s College of Arts and Sciences. McCracken, who has studied bats for over 20 years, provides four fascinating facts about the winged creatures:

Vampire bats are a real thing.

There are only three species of vampire bats, and they all live in Mexico. They are also very small, weighing only between 25 and 30 grams (0.88 to 1.05 ounces).

They feed on domestic animals, such as cows and goats, as well as birds. And, yes, they can occasionally feed on a sleeping human.

While they drink blood, they don’t remove enough to harm their host. However, their bites can cause infection and disease.

Fair warning: With climate change, these bats are expanding their range upward. “It won’t be too long before we see them in southern Texas or Florida,” McCracken said.

Bats don’t actually suck blood.

Contrary to what horror movies would have us believe, bats don’t suck blood, but they do lap it with their tongues. And they don’t use their incisors either.

“Instead, they use their front teeth to make a small cut, and through the rapid movements of their tongues they create a little stream of blood they feed from,” McCracken explained.

Their saliva has a topical anesthetic, too, so the animal they’re biting will likely not feel anything.

If that blew your mind, get this: their saliva is also loaded with an anticoagulant that is very sought after by pharmaceutical companies to treat strokes created by blood clots.

They can boost the economy.

Bats are generalist insectivores, meaning that they will eat just about any insect out there. In doing so, they are of great help to farmers everywhere, bringing in a hefty economic benefit.

“We estimate their help to be valued in between $3.7 to $53 billion a year in avoided crop damage,” McCracken said.

By eating insects, they can also help reduce the amount of pesticides needed to grow healthy crops.

They have the super power of echolocation.
Finding food is difficult in the dark. Since most bats are nocturnal creatures, they have to rely on a special technique called echolocation.

Echolocation works much like a radar: bats emit high-frequency noises as they fly, and the returning echoes help them know how far away they are from an object.

“Their facial features are adapted for the emission and reception of these high-frequency noises,” said McCracken.

Bonus tip: If you’re searching for a fun bat movie to watch this Halloween, McCracken recommends his all-time favorite, Nightwing, a 1979 film about giant vampires attacking people in the United States.

“It’s so ridiculous it’s funny,” McCracken said.

CONTACT:

Andrea Schneibel (andrea.schneibel@utk.edu, 865-974-3993)