Everybody knows that if you come face to face with a bat, there are only two possible outcomes: you either become Batman or you turn into a vampire.
The first option is not so bad; you’re automatically in the best shape of your life, you’re richer than you could ever imagine, you have a lifelong purpose that you’re devoted to and believe in, and Christian Bale is portraying your life on the silver screen (let’s not talk about Ben Affleck). The second option is not so great; yes you get to live forever, but you have to give up cheeseburgers and milkshakes, you can never get tan, and you have to cut garlic out of your diet…no thank you.
So let me paint a word picture of a scenario you will probably find yourself in someday. You are out on a Thursday night walking your Pomeranian named Christian (named after Christian Bale your favorite actor), and you look down and six feet in front of you, on the ground, is a bat, and it looks like the kind that will turn you into a vampire.
You wonder, “Am I in danger? Are bats able to take off from the ground? And if so, should I have bought that house with that creepy cave underneath that somehow is hooked up to absurd amounts of power to run all sorts of gadgets?”
I can’t answer the last question, but I can answer the other two: Most bats cannot take off from the ground, though there are some exceptions. Their unique flight style arises from adaptions in their biology, specifically their wings and feet.
Bat Wings
Bats have developed several adaptations that have allowed them to be the only mammal that is capable of sustained flight. Though these adaptations have limitations and advantages when compared to their neighbors in the sky: birds.
Though there are limitations, bats’ ability to fly is no less impressive. In fact, the Mexican Free Tailed Bat has been recorded to fly up to 100 mph.
At first glance, bats seem to fly exactly the same way as birds: by using their wings to create upward force and momentum, thus propelling them into the air. It is true, like birds, it is the bat’s wings that allow it to fly, but that is where the similarities stop.
Bats’ wings are structured differently than birds, and thus operate differently in their flight pattern.
Bats have much more bones in their wings than birds do, and with more bones comes more joints. And bats’ joint are particularly flexible.
When a bat spreads its wings, you can see these bones and joints spreads throughout the bat’s wings like spindly fingers.
These spindly finger bones are connected by a thin membrane that takes up the bulk the surface area of bats’ wings. This membrane is fragile and prone to tearing, leaving bats vulnerable to injuries that keep them from being able to fly until their membrane heals, which luckily for the bat, happens very quickly.
Because bats’ wings are thin with many joints throughout the wing, they are able to maneuver more adeptly than birds, whose wings are thicker and stiffer. These adaptations cause bats’ flight pattern to be up to 35% more energy proficient than most birds.
Yet, these adaptations also come with limitations. Because bats’ wings are comprised by a single membrane, bats cannot reduce their wingspan in flight, in other words, to achieve thrust, bats must fully stretch out the membrane by extending their wings to full capacity, which requires proportional more space needed for takeoff.
Birds, which have wings made up of hundreds of individual feathers, do not have this limitation, and are thus able to reduce their wingspan to reduce drag and simply glide. This means that bats are not able to fly long distances like birds.
Though these adaptations are interesting, and differentiate bats from birds in terms of flight, they do not fully explain why bats are not able to take off from the ground. That adaptation has to do with their feet.
Bat Feet
Yes, bats have feet.
Birds’ feet are disconnected from their wings, they’re entirely separate appendages. This allows them to use their feet to launch themselves into the air high enough for their wings to do the rest.
Bats are not so gifted; bats’ feet are attached to their wings. This adaptation helps them maneuver more adeptly in the air, but it limits their ability to move along the ground.
Think about it like this: have you ever tried to run anywhere with your feet tied together? Or maybe you have done the “waddle- to-the-cabinet-with-your-pants-around-your-ankles-to-see-if-there-is-any-toilet-paper-left” walk?
Your range of motion is limited, you’re not able to move quickly, you’re more prone to tripping. Admit it, we have all been there.
That is how bats walk all the time. Add that with the extra room needed for takeoff and you have a result that doesn’t mix well with the ground.
This is why most bats cannot take off from the ground. They simply cannot generate enough speed or space with their feet attached to their wings to take off because it is as though their feet were tied together.
But don’t worry, Bats have a solution to this dilemma, and it has to do with how bats like to hang out… literally.
Bats spend a lot of time hanging upside down, like that one kid on the playground who is in gymnastics. Because their feet are attached to their wings, it is actually easier for them to land feet first on a branch or ledge, and that usually means that they’re landing upside down.
To take off, bats simply let go of their perch and use the two-to-three-foot drop to generate enough speed and space to take flight. Kind of like a running start, except the opposite: a falling start.
The Exceptions
Most bats do not have the ability to take off from the ground, but there are some notable exceptions.
Most of the bats that have adapted to life on the ground have smaller bodies and shorter wings. The New Zealand Short Tailed Bat is an example of this.
Because New Zealand is almost entirely bereft of large predators and ground mammals, the New Zealand Short Tailed Bat spends much of its time on the ground searching for bugs to eat and has thus developed the ability to take off from the ground.
Another exception is none other than the Vampire Bat. The Vampire Bat tends to stalk its prey by sneaking up to it on the ground before pouncing in attack.
Not only is this terrifying, but it is particularly bad news for you and your dog, Christian, as you come face to face with a grounded bat on an average Thursday night in Milwaukee (did I mention you’re going to end up in Milwaukee?).
You have a choice, you now know that most bats can’t take off from the ground, so you’re probably safe, but this might be a vampire bat, and no one wants to become a vampire.
However, there is the slight chance you will become Batman, which is pretty cool. But at the same time, more money, more problems.
