15 Questions Not All Adults Know How to Answer
The world is huge, and every single person in it asks dozens of questions about it. Even though the answers might not be very important, they’re still interesting. For example, why some people are annoyed by slurping and others aren’t, why older people can’t sleep for a long time, and many other things.
Why the hands of the clock go from left to right
The oldest known sundial was made in Egypt in 1500 B.C.E., and it was the prototype for the modern clock. The people who made it lived in the Northern Hemisphere and watched the Sun go from East to West and the shadow move from left to right. So, when mechanical clocks started to appear much later, the hands were moving from left to right.
Why we feel colder in the water even though the air temperature is the same
It’s related to the thermal conductivity of materials. Our skin heats the air very quickly when they get in contact, but the water takes longer to heat, so it feels much colder.
Why cats start running after using the toilet
Cats have a vagus nerve that goes down from their brain stem, much like humans. Pooping can activate this nerve, so cats start running to wear off the extra energy.
Why the part of the ship that is underwater is painted red
In the past, ships were covered with copper to prevent sea creatures from sticking to them. Now, there are better solutions. One of them is a special paint that contains copper oxide. It achieves the same effect as the copper sheets used in the past.
Why manhole covers are round
First of all, a round cover can’t fall through the hole it’s covering. Moreover, being so heavy, this shape makes them easier to roll. And round covers are much more durable than square-shaped ones, for example.
Why older people wake up early
From ages 60 to 65, our circadian rhythms reset to an earlier time. They shift by approximately half an hour every decade. It’s often caused by a lower production of melatonin in the body, so older people wake up earlier.
Why cats have vertical pupils
Cats, and other ambush predators that are not bigger than 16.5 inches, have vertical pupils to be able to estimate the distance to the prey and choose the right jump force. The pupil shape is vertical because cats hunt from the ground. Meanwhile, lions, tigers, and other felines have round pupils because they are bigger.
Why we are annoyed by certain noises
We sometimes feel enraged by certain sounds. They might be slurping, cracking joints, or crying. Such sounds can cause anger, panic, fear, or stress. It turns out that this phenomenon is called misophonia.
In most cases, misophonia first appears at the age of 9-13, and mostly in girls. Scientists are still researching how it develops, but it probably has to do with the central auditory system of the brain.
Why yawning is contagious
According to one of the theories, yawns are contagious due to mirror neurons that make us copy what we see. It also works for animals, you might have noticed that pets yawn when people do.
Why cats like the smell of bleach
You might have noticed that cats start smelling those places where bleach was used. The thing is, bleach contains chlorine, which causes this reaction in cats. Researchers believe that chlorine contains something that reminds cats of pheromones. This is why they enjoy this smell so much.
Why certain smells can awaken memories
The limbic system is the part of the brain responsible for many different functions, including the processing of smells. When we smell something familiar, the signals go right into the limbic system, which makes us have feelings and emotions. Specialists even use this effect in working with patients suffering from dementia.
Why we laugh when we’re tickled
A study has shown that both laughing at jokes and laughing when we’re tickled activate the part of the brain that controls facial movements, and vocal and emotional reactions. But laughing when being tickled also activates the hypothalamus, the area of the brain that regulates the fight or flight response. This has led some scientists to believe that laughing when you’re tickled could be a natural signal of submission to an aggressor, which would reduce the duration of any attack.
What the holes in plane windows are for
The holes in window planes are there to balance the pressure and get rid of the extra air. The tiny window hole has another purpose, which is to release moisture and stop frost or condensation from blocking your view.
Why doctors can’t tie the belly button to make it attractive for all people
The shape of the belly button doesn’t depend on the talent of the midwife or obstetrician. It’s determined by genes. It has to do with how much of the baby’s skin is connected to the umbilical cord. But, fortunately for those who don’t like their belly buttons, there’s a special surgery that can change its shape.
Why cats have rough tongues
Cats are solitary animals and they need to make sure they are clean in order not to become prey because of their smell. These rough tongues help them wash their fur very carefully. Also, such tongues help them eat by licking food of very different textures.
Did you know the answers to these questions? Do you know some other interesting things about the world?