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How Do Bats Hang Upside Down? Interesting!

How Do Bats Hang Upside Down? Interesting!

I was doing some bar work at the gym recently, and as I began feeling a little dizzy from being upside down. I suddenly wondered, just how do bats hang upside down

So, I went to the local zoo for some answers. Like me, you will also be amazed at how amazing bats really are.


How Do Bats Hang Upside Down?

Bats hang upside down for them to fly. Their wings are weak and they can’t take off from the ground. So their bodies adjust to help them hang upside down: their knees face the wrong way and they have special tendons that help their toes clamp onto branches and rocks without effort. Once they’re hanging upside down, they don’t need any muscle strength.


Adjustments Bats Have to Hang Upside Down

For bats, it is essential that they hang upside down to enable them to just drop into the sky and fly.

They can’t run for take-off or flap their wings to gain lift-off, so they need to be upside down to fly. Therefore, they sleep upside down too.

Since bats aren’t as big as humans or other animals, they can easily negate the effects of gravity, which cause our circulation to send blood to our heads and, as a result, we feel dizzy.

Therefore, bats don’t get dizzy from hanging upside down at all! Their hearts are powerful enough to maintain circulation in their small bodies even when upside down.


Bat Tendon Connections

While our tendons connect to our muscles, which is why our arms bulge when we make a fist, bats have their talon tendons connected straight to their upper body. There is no muscle involvement.

So, when a bat wants to hang upside down, it needs to only grab a perch, let its body sag down and the act of hanging is what closes the talons.

As long as a bat has weight dropped down on its talon tendons, it won’t let go. This is why even when bats die, they can remain hanging!

With no continuous action required, a bat can hang for hours without any muscle fatigue. Imagine doing bar lifts for hours on end!

Our muscles would be quivering with excretion in a few minutes, yet a bat can simply let their body weight close up their talons by pulling their leg tendons straight so they can hang effortlessly.


Bat Lift-Off Mechanism

When a bat is ready to let go, they use muscles to lift their body, releasing their tendons, which connect to the talons that will then open. As a result, with a small amount of energy, a bat can let go, drop down, and fly.

This is where those backward knees are handy.

A bat can hook onto the ceiling or branch they are hanging from with their wing claw (or thumb), pull themselves up enough to lift the weight off their talon tendons, which detaches them to release, drop down, and fly.

Bats can also effortlessly use their core strength and the backward-facing knees to pull themselves up enough to detach their claws to let go.

Remember, as long as there is a weight suspended from their claws or talons, their leg tendons are lengthened and the claws will remain closed.

This is also why a bat may struggle to let go of your hand if it is hanging there and unable to pull itself up.


A Major Drawback of Hanging Upside Down to Fly

While the evolutionary idea of simply dropping into the air and flapping has worked wonders for bats, there are a few drawbacks.


Hard to Launch When Flat

Bats can’t fly up off the ground. So if they have fallen from the sky, they need to crawl to a wall or tree, find a higher elevation, get upside down into their launch position, and then drop into flight.

When bats are not in the hanging position, flight is not an option for them.

This explains why I often find dead bats around buildings. They fall out of the roof sidings when learning to fly, and as a result, they can’t fly again.

Bats may end up dying when they can’t fly as they can’t forage for insects then.

Flapping wings is also how bats generate heat and if they can’t flap their wings, they will get pneumonia and die. Bats can only flap their wings while hanging upside down or when flying.


Frequently Asked Questions about How Bats Hang Upside Down


How do bats hang upside down and poop or pee?

Bats don’t have any problem using the potty when hanging upside down. Their dung is as small as a grain of rice, which means it easily drops to the floor. To pee, bats wait until they are in flight before they pee. Small bat pups are cleaned by their mom, and it isn’t uncommon to see female bats with their litter of pups hanging on during flight. Therefore, even baby bats know how to hang on and also spend most of their lives upside down. Hanging upside down is then not something bats learn to do. They are born with the ability.


How do bats hang upside down and give birth at the same time?

The mother bat hangs upside down, her talon tendons supporting her as her body weight hangs on these, locking her talons in place on her perch. She gives birth upside down and using her wings, she will catch her blind newborn pup. Using the same weight mechanism, the baby bat will latch onto its mother in the upside-down position too.


The Final Hang Out

Bats are amazing mammals. They are equipped for an upside-down life, and nature has ensured they can fly even though they lack the power to take to the sky on their own.

So, with a simple drop-in action, they can launch into flight.

With the use of their unique weight-locking tendon mechanism, bats can hang effortlessly for hours on end, even in death, until they are ready to detach and fly away.

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