My wife told me an amazing fact she had picked up from a Russian account on TikTok.

For years, the story goes, scientists believed bats were extremely good at echolocation. That was how they flew around dark caves without constantly hitting the walls. Then one scientist X-rayed a batch of bats and found that many of them carried multiple healed fractures. Bats were not brilliant navigators after all. They were terrible at echolocation, crashing into things and breaking bones the whole time. They were just extraordinarily good at healing.

It is a great fact. Specific, funny, and it overturns something everyone assumes they know. It even comes with a scientist, an experiment and physical evidence. I wanted to write about it immediately.

There was only one problem. It does not appear to be true.

The short answer

Bats really are good at echolocation. They are not infallible and they do sometimes hit things, but nobody ever X-rayed a pile of bats, found a mess of old fractures, and concluded that the field had it backwards all along.

The closest thing I could find was a single published report of one wild big brown bat flying around with a healed fractured radius, plus research showing that wounds in bat flight membranes heal well. Neither supports the story.

So it is a joke, or a garbled retelling of something real, or an invented internet fact. I cannot tell which without tracking down the original video. The part that interests me is that I believed it long enough to repeat it.

The real discovery of bat echolocation

Nobody worked out echolocation by noticing an absence of concussed bats on cave floors.

In the late eighteenth century, the Italian biologist Lazzaro Spallanzani observed that bats could navigate in darkness even when they could not see. Experiments by Spallanzani and the Swiss researcher Louis Jurine pointed toward hearing, though nobody yet knew that ultrasound existed.

The decisive work came about 150 years later. In the late 1930s and early 1940s, Donald Griffin and Robert Galambos got hold of equipment that could detect ultrasonic calls, and flew bats through rooms strung with suspended wires. The bats dodged the wires when they could call and hear. Obstruct either the calling or the hearing and they struggled. Their 1941 paper was The Sensory Basis of Obstacle Avoidance by Flying Bats, and Griffin later coined the word echolocation.

Later experiments measured how sensitive the system can be. In one obstacle-avoidance study, bats successfully avoided vertical wires only 0.065 millimetres thick. Echolocating bats also locate and intercept tiny flying insects in complete darkness. Rapid bone repair does not explain that.

But bats really do crash into things

This is where the fake fact turns annoyingly clever, because bats genuinely do hit things. Their sonar has blind spots.

In a 2017 study published in Science, researchers found that bats sometimes flew directly into smooth vertical surfaces. Glass and polished metal behave like acoustic mirrors. Rather than returning an echo to the approaching bat, a smooth surface reflects most of the sound away at an angle. To the bat, it can sound like an open flight path until it is dangerously close.

That matters most around modern buildings. A cave wall is rough and scatters echoes back from many angles. A large sheet of glass is not something bat echolocation evolved to handle.

Bats can also be fooled by their own expectations. A 2025 study of Egyptian fruit bats trained bats to land on a perch and then moved it. Some bats kept flying toward the old location despite receiving current sensory information about the change. The researchers described this in terms of learned spatial expectations and where the bats were directing their attention.

So bats do make navigation mistakes. That is not evidence that echolocation barely works. Humans walk into freshly cleaned glass doors despite having excellent vision, and nobody concludes that eyesight is a myth and people simply have unusually fast noses.

And bats really can heal injuries

There is a grain of truth in the broken bones, too.

In 2003, researchers described an adult big brown bat caught in a Toronto attic with a healed fracture in the radius of one wing. It was trapped along with the rest of its colony, and its flight looked irregular. The X-ray showed a break that had knitted back together while offset, already well into remodelling, with no sign that a human had ever repaired it. The bat could fly for extended periods.

That is a remarkable case, but it is one bat with one healed fracture. It is not a population riddled with evidence of repeated cave-wall collisions.

Flight membranes repair themselves as well. A 2009 study in the Journal of Mammalogy followed healing after researchers took small circular biopsies from the wing and tail membranes of 32 big brown bats. The wounds closed at different rates depending on size and location, and tail-membrane wounds healed faster than wing wounds. Later research found that season and reproductive state affected healing too.

But a flight membrane is living skin, with blood vessels and nerves and connective tissue running through it. Healing a small hole in one is nothing like rapidly rebuilding a shattered forearm, and none of this research suggests that bats routinely smash themselves apart and carry on as though nothing happened.

Why the false version sounded so convincing

The TikTok story is almost engineered to slip past a sceptical brain.

Every individual component is plausible:

  • bats live and fly in dark places
  • bats use echolocation
  • animals sometimes collide with things
  • old fractures show up on X-rays
  • some animals have impressive healing abilities

Every one of those is true. The falsehood lives in the joints between them.

Then there is the shape of the thing. It imitates science without offering anything you can check. It has “scientists,” but no names. It has an X-ray study, but no species, institution, journal or date. It describes a dramatic reversal of scientific consensus without a paper or any follow-up work. Those gaps should have been the warning. Instead, the mention of a scientist and an X-ray made the claim feel documented.

It also reached me through someone I trust. My wife was not claiming to have examined bat skeletons herself. She was passing along a delightful fact. By the time it got to me, the original TikTok account had dropped out of the chain entirely and the source had effectively become her.

Familiarity alone nudges us toward believing things, an effect known as the illusory truth effect. Endorsement matters too: experiments have found that misleading posts seem more credible when a trusted person appears to be passing them along. None of this means people are stupid. It means that evaluating every harmless fact from first principles would make ordinary conversation impossible.

A ten-second test for amazing internet facts

I do not want to become the person who interrupts a nice dinner to demand a DOI. Most strange facts are harmless, and half the pleasure is in passing them on.

Before publishing one, though, it is worth running through a few questions. Can I name the actual source? “A scientist discovered” is not a source. Can I find the original study, by searching for the central claim rather than for the pages that repeat it? Do the reputable results reach the same conclusion, or do they merely share keywords? Is the story suspiciously perfect, with a funny reversal and a neat ending, in the way that constructed entertainment usually is? And could the whole thing simply have been a joke? Tone and attribution fall away quickly when a video crosses platforms and languages.

Professional fact-checkers call the useful version of this lateral reading: leave the original page and open new tabs to investigate the claim and whoever made it. That is exactly what worked here. Reading the original story more carefully would have achieved nothing, because it contained no evidence to inspect.

The verdict

Bats are good at echolocation. They make mistakes, particularly around smooth artificial surfaces. At least one wild bat has been documented flying with a naturally healed fracture, and their wing membranes really do heal.

But the wonderful claim that bats are secretly terrible at echolocation and merely heal from their constant crashes has nothing behind it.

I am slightly disappointed. It was a much better fact than the truth.

It did turn into a useful example of something else, though. Misinformation does not only arrive as propaganda or a dangerous medical claim. Sometimes it arrives as a charming story about incompetent bats, and I suspect those are the ones that travel furthest.

Sources