WHY haven't humans tamed zebras?
As early as the 19th century, colonizers thought of domesticating zebras in Africa to avoid transporting horses to the continent. Zebras are also resistant to diseases carried by the tsetse fly.
Yet unlike horses, which are carefree, zebras are in a constant state of stress, running away and even sometimes fighting savannah predators. Cornered, a zebra can beat a lion to death.
As early as the 19th century, colonizers thought of domesticating zebras in Africa to avoid transporting horses to the continent. Zebras are also resistant to diseases carried by the tsetse fly.
Yet unlike horses, which are carefree, zebras are in a constant state of stress, running away and even sometimes fighting savannah predators. Cornered, a zebra can beat a lion to death.
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WHY do worms crawl out after it rains?
Roughly 50 years ago, biologists believed that earthworms crawl to the surface after it rains to avoid drowning in their own burrows. However, this theory was rejected as they breathe through their skin, and a wet environment is ideal. There are several hypotheses at this point:
โก๏ธFor easy migration: it is easier for them to travel distances by crawling on a wet surface than by creating passages in the soil.
โก๏ธ Escape from the enemy: raindrops hitting the ground are like vibrations from the movement of predators such as moles.
Roughly 50 years ago, biologists believed that earthworms crawl to the surface after it rains to avoid drowning in their own burrows. However, this theory was rejected as they breathe through their skin, and a wet environment is ideal. There are several hypotheses at this point:
โก๏ธFor easy migration: it is easier for them to travel distances by crawling on a wet surface than by creating passages in the soil.
โก๏ธ Escape from the enemy: raindrops hitting the ground are like vibrations from the movement of predators such as moles.
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WHY can't people breathe and swallow at the same time?
The complex structure of the adult vocal apparatus does not allow humans, unlike animals, to breathe and swallow at the same time.
โ๏ธBehind the root of the tongue is the supraglottic cartilage (epiglottis). It closes the entrance to the larynx when a food lump is swallowed, then opens to allow air to pass into the larynx and then through the respiratory tract.
The complex structure of the adult vocal apparatus does not allow humans, unlike animals, to breathe and swallow at the same time.
โ๏ธBehind the root of the tongue is the supraglottic cartilage (epiglottis). It closes the entrance to the larynx when a food lump is swallowed, then opens to allow air to pass into the larynx and then through the respiratory tract.
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WHY do runners get off to a low start?
Before 1887, all athletes started the race from a standing position.
Then, after observing a kangaroo, the American sprinter Sherrill decided to try a new starting position. As for kangaroos, they duck to the ground just before the start.
Despite the protest of the judge and the mockery of the spectators, Sherrill applied the new method and immediately won the race.
Before 1887, all athletes started the race from a standing position.
Then, after observing a kangaroo, the American sprinter Sherrill decided to try a new starting position. As for kangaroos, they duck to the ground just before the start.
Despite the protest of the judge and the mockery of the spectators, Sherrill applied the new method and immediately won the race.
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WHY is it better to breathe through the nose in the cold?
The nasal cavity exhibits a unique ability to raise or lower the temperature of inhaled air. When it is -25 C outside, the air in a person's nasal cavity heats up to +35... +36,6 ะก.
As opposed to the oral cavity, the nasal one heats the air much more effectively. It is like a built-in split system that ensures normal functioning of the lower respiratory tract.
The nasal cavity exhibits a unique ability to raise or lower the temperature of inhaled air. When it is -25 C outside, the air in a person's nasal cavity heats up to +35... +36,6 ะก.
As opposed to the oral cavity, the nasal one heats the air much more effectively. It is like a built-in split system that ensures normal functioning of the lower respiratory tract.
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WHY is a zebra black with a white stripe and not vice versa?๐
Many people are convinced that a zebra is a white horse in a black stripe cause zebras have white bellies.
Scientists posed this tricky question and found out that zebras are black with a white stripe even at the embryonic stage, not the other way around.
โBlack is the main pigment, and white stripes are the lack of it.
Many people are convinced that a zebra is a white horse in a black stripe cause zebras have white bellies.
Scientists posed this tricky question and found out that zebras are black with a white stripe even at the embryonic stage, not the other way around.
โBlack is the main pigment, and white stripes are the lack of it.
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WHY are the "black boxes" in airplanes actually red or orange?
A "black box" is a device installed in an airplane to record information about the technical condition of all devices, as well as the actions and conversations of the crew.
Actually, it is not a box, but rather a ball or cylinder. And its color is not black, but red or orange, to make it easier to find in case of an accident.
A "black box" is a device installed in an airplane to record information about the technical condition of all devices, as well as the actions and conversations of the crew.
Actually, it is not a box, but rather a ball or cylinder. And its color is not black, but red or orange, to make it easier to find in case of an accident.
WHY does stress cause a lump in the throat?
This tells us that the body's autonomic nervous system (ANS) is struggling with the stressful situation. This system is independent of the human will and functions autonomously.
When we're nervous, the ANS tries to oxygenate the body as much as possible. To do this, it forces us to breathe faster and expands a part of our throat called the vocal cleft so that air gets through faster.
๐ The feeling of muscular resistance to closing the throat when we try to swallow is the "lump in the throat".
This tells us that the body's autonomic nervous system (ANS) is struggling with the stressful situation. This system is independent of the human will and functions autonomously.
When we're nervous, the ANS tries to oxygenate the body as much as possible. To do this, it forces us to breathe faster and expands a part of our throat called the vocal cleft so that air gets through faster.
๐ The feeling of muscular resistance to closing the throat when we try to swallow is the "lump in the throat".
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WHY do scorpions have blue blood?
The fact is that the blood of scorpions does not contain hemoglobin, but hemocyanin, its analog. If hemoglobin is an iron-containing substance, then hemocyanin consists of copper.
When in contact with air, this element turns blue and, giving oxygen to tissues, loses its color.
The fact is that the blood of scorpions does not contain hemoglobin, but hemocyanin, its analog. If hemoglobin is an iron-containing substance, then hemocyanin consists of copper.
When in contact with air, this element turns blue and, giving oxygen to tissues, loses its color.
WHY are there no old houses in Japan?
In this country, it is believed that a house loses value from the first day it was built. Within 10 years, such value is halved. After 25 years, it is considered overly old to live in and has no value whatsoever. After that, it is demolished and a new house is built in its place.
Even landmarks and important shrines are regularly rebuilt. That's why there are no examples of old architecture in Japan โ all the houses are modern.
In this country, it is believed that a house loses value from the first day it was built. Within 10 years, such value is halved. After 25 years, it is considered overly old to live in and has no value whatsoever. After that, it is demolished and a new house is built in its place.
Even landmarks and important shrines are regularly rebuilt. That's why there are no examples of old architecture in Japan โ all the houses are modern.
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WHY does a dolphin sleep with one eye open?
Dolphins are able to sleep by alternately turning off one of their hemispheres. The other hemisphere is awake at that moment. Accordingly, one eye is open in order to monitor changes in the environment.
If the right hemisphere sleeps and the left one is awake, the right eye is open. And vice versa.
Dolphins are able to sleep by alternately turning off one of their hemispheres. The other hemisphere is awake at that moment. Accordingly, one eye is open in order to monitor changes in the environment.
If the right hemisphere sleeps and the left one is awake, the right eye is open. And vice versa.
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WHY does the British Queen lack of a passport?
Even though the Queen does not have a passport, she is free to travel around the world.
Since UK passports are issued in Her Majesty's name, the Queen does not need one. All other members of the royal family have passports.
Also, the Queen is the only person in Great Britain who is allowed to drive a car without a license.
Even though the Queen does not have a passport, she is free to travel around the world.
Since UK passports are issued in Her Majesty's name, the Queen does not need one. All other members of the royal family have passports.
Also, the Queen is the only person in Great Britain who is allowed to drive a car without a license.
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WHY are Japanese suicide bombers called kamikazes?
The Mongol khan Kublai twice planned an invasion of Japan, and both times he was prevented by violent typhoons.
The Japanese saw this as a help from above and called them "kamikaze," which means "divine wind." And in World War II they used the term to describe suicide pilots.
The Mongol khan Kublai twice planned an invasion of Japan, and both times he was prevented by violent typhoons.
The Japanese saw this as a help from above and called them "kamikaze," which means "divine wind." And in World War II they used the term to describe suicide pilots.
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WHY do calculators start at the bottom and the phone starts at the top?
The calculator is the successor of cash registers and mechanical counting machines. That's why the numbers on the calculator from zero to nine are from the bottom to the top.
Until the 1960s, dialing on the telephone was done with a dial. Then tone dialing became possible, and the familiar dial was replaced by buttons.
There were many different attempts: they were arranged in a circle, or in two rows... But as a result, the familiar option was chosen, where the numbers are arranged in three rows in ascending order (from top to bottom).
The calculator is the successor of cash registers and mechanical counting machines. That's why the numbers on the calculator from zero to nine are from the bottom to the top.
Until the 1960s, dialing on the telephone was done with a dial. Then tone dialing became possible, and the familiar dial was replaced by buttons.
There were many different attempts: they were arranged in a circle, or in two rows... But as a result, the familiar option was chosen, where the numbers are arranged in three rows in ascending order (from top to bottom).
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WHY are extroverts and introverts ideal life partners?
โก๏ธ Extroverts tend to be active, sociable people. They easily establish contact with others. They can also be inspiring and encouraging.
โก๏ธ Introverts are quiet ones. Take a long time to think through decisions, analyze all options. Able to avoid problems.
Therefore, calm introvert keeps from making rash decisions, and temperament extrovert rouse the other half.
โก๏ธ Extroverts tend to be active, sociable people. They easily establish contact with others. They can also be inspiring and encouraging.
โก๏ธ Introverts are quiet ones. Take a long time to think through decisions, analyze all options. Able to avoid problems.
Therefore, calm introvert keeps from making rash decisions, and temperament extrovert rouse the other half.
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WHY is everything colored green in night vision devices?
In traditional night vision devices (not thermal imagers), light entering the lens is converted into shades of black and white, and only when it hits the phosphor screen does it take on a greenish hue.
The green gamut is chosen for two reasons:
โ the human eye is most susceptible to waves of this length.
โ it is the least tiring to the eye for prolonged exposure.
In traditional night vision devices (not thermal imagers), light entering the lens is converted into shades of black and white, and only when it hits the phosphor screen does it take on a greenish hue.
The green gamut is chosen for two reasons:
โ the human eye is most susceptible to waves of this length.
โ it is the least tiring to the eye for prolonged exposure.
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WHY are the ribs of coins notched?
Coins used to be valued according to the amount of metal they contained. Fraudsters used to cut the metal off the edges, pocketing the gold and silver. It was incredibly difficult to catch them.
A solution to this problem was suggested by Isaac Newton, who was an employee of the British Royal Mint. He suggested making fine notches on the edges of the coin, which made the worn edges immediately visible.
Coins used to be valued according to the amount of metal they contained. Fraudsters used to cut the metal off the edges, pocketing the gold and silver. It was incredibly difficult to catch them.
A solution to this problem was suggested by Isaac Newton, who was an employee of the British Royal Mint. He suggested making fine notches on the edges of the coin, which made the worn edges immediately visible.
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WHY does the skin on fingers get wrinkled in water?
Our distant ancestors used to extract from water bodies not only food, but also household items. No special equipment was available, so they had to do it with their bare hands.
Skin wrinkling on palms and fingers made the task a lot easier and changing the skin on feet simplified moving over underwater rocks and other slippery surfaces.
Our distant ancestors used to extract from water bodies not only food, but also household items. No special equipment was available, so they had to do it with their bare hands.
Skin wrinkling on palms and fingers made the task a lot easier and changing the skin on feet simplified moving over underwater rocks and other slippery surfaces.
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WHY do cats purr?๐
The sound and vibration are created by the muscles inside the cat's larynx.
When they move, the vocal cleft expands and contracts. The air vibrates every time the cat inhales and exhales.
What do we end up with? Purring.
The sound and vibration are created by the muscles inside the cat's larynx.
When they move, the vocal cleft expands and contracts. The air vibrates every time the cat inhales and exhales.
What do we end up with? Purring.
WHY don't mice like cheese?
Contrary to popular myth, mice are not as big a fan of cheese as they are often portrayed in cartoons and even movies.
The basic diet of mice, like other rodents, consists of grains, seeds, pieces of vegetables, fruits and sweets. In addition, many cheeses have a pungent odor that is more likely to scare away a mouse.
Contrary to popular myth, mice are not as big a fan of cheese as they are often portrayed in cartoons and even movies.
The basic diet of mice, like other rodents, consists of grains, seeds, pieces of vegetables, fruits and sweets. In addition, many cheeses have a pungent odor that is more likely to scare away a mouse.