Certain things that we think we know about animals may not be true after all.
Did you know that hordes of lemmings sometimes commit mass suicide, or that if you cut yourself in the ocean, sharks from miles away will be able to smell your blood? You may have heard these things and others like them before, but they’re actually untrue. Cartoons, movies, and many other “sources” of information have been rife with animal myths, like how ostriches bury their heads in the sand when they think they’re in danger. If these are myths and nothing more, then what other tidbits of common knowledge are actually false?
If you ever cut yourself on a rock or a coral while swimming in the ocean, sharks aren’t what you need to worry about. You’d actually need to worry more about cleaning your wound, but let’s get back to those sharks for a minute.
It’s true that sharks have a particularly strong sense of smell. Shark nostrils, unlike those of humans, are used exclusively for smelling and not for both smelling and breathing. These nostrils are lined with extremely sensitive specialized cells that contain receptors, which are in turn capable of detecting chemicals in the water that pass into the nostrils. The shark’s brain then interprets these signals as smells. Thus, sharks are able to detect a drop of blood in an amount of water equivalent to the amount in an Olympic-sized pool.
However, the ocean has a lot more water than a pool, even one that’s Olympic-sized. It’s therefore going to take a significant amount of time for odor molecules to reach sharks.
Sometime ago, someone seriously thought that sexual intercourse with a monkey introduced the HIV virus to the human population. However, this was only an over-sensationalized possible explanation. Sex wasn’t the primal urge that facilitated the transfer of the virus to human beings. It was hunger.
Scientists think that hunting monkeys for bush meat may have led to the rise of HIV. A hunter may have brought down a monkey that carried a simian immunodeficiency virus, and blood contact may have introduced the virus to human bodies.
Here’s a funny thing about ostriches: they stick their heads in the sand when they’re scared, because if you can’t see what scares you, it stops existing!
None of that is actually true. In fact, ostriches don’t even bury their heads in the ground for any reason at all. When ostriches sense danger nearby, they flop to the ground and play dead. The color of their feathers allows them to blend in with the color of the sand, which then keeps them safe. This position, however, makes it look as if an ostrich is burying its head in the sand.
Still, ostriches don’t just rely on passive methods to keep themselves out of danger. They can also deal serious damage, even to grown lions, if they choose to fight.
If you touch a frog or a toad, you get warts—or at least that’s how the myth goes. However, the reality is that you’re far more likely to get warts from a friend than from a frog.
Warts occur on on an infected part of the top layer of our skin. They’re caused by some viruses among the human papillomavirus (HPV) family, which can occur only in humans. Thus, there’s no interspecies contagion going on there.
We all come across HPV in our lives. Most of us will get warts at least once in our lives, usually on the hands, since HPV can be found on doorknobs, keyboards, and yes, other people’s hands.
Anyone who has ever been a teenager has probably heard this at least once in their lives: “if you friends jump off a cliff, are you going to jump, too?”
It’s unclear how this myth started, but according to it, lemmings commit mass suicides by simply marching off the edge of a cliff en masse. The truth, however, is that lemmings don’t purposefully just jump off of cliffs in droves.
Of course, there’s actually more to that. While they don’t purposefully fall off cliffs, they sometimes do so accidentally. Lemmings reproduce more quickly than other animals, and because of that, their populations grow at a faster rate. They usually break apart in subgroups when food becomes scarce, and these subgroups spread out to fund sustenance. In their journeys, they may sometimes find themselves falling into bodies of water, simply because they refuse to let anything get in the way of finding food.
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