WHY do midges tend to fly in swarms?

As a rule, it is a mating flight.

A swarm usually consists of insects of one sex and serves to attract the other sex. A swarm probably has a much more powerful pheromone flow, and a group of insects can be seen and heard from afar.

This form of mating behavior is characteristic of many small bipeds, colloquially called midges.

WHY do legumes make us gurgle?

Indeed, the substances in legumes (oligosaccharides) become food for probiotic bacteria when they enter the intestines. As a result, the stomach begins to bloat, and sometimes with unwanted sounds and smells.

This effect can be reduced by soaking legumes before cooking.

WHY are probiotics useful?

Probiotics are bacteria that are proven to benefit the human body. The most common probiotics are lacto- and bifidobacteria. Other microorganisms can also be classified as probiotics, such as the yeast Saccharomyces boulardii.

In the human gut, probiotics compete with harmful bacteria, suppress their growth and maintain the protective barrier of the intestinal walls. In this way, they reduce the likelihood of inflammation.

WHY does a person count the days by drawing sticks and then crossing them out?

If you count just with sticks, it takes a long time to count them by looking at the drawing. But if you draw 4, and then cross out these 4, then a quick glance is enough to realize that it is 5.

Plus a psychological moment - by crossing out a group of sticks, we as though summarize, finish a certain stage.

Perhaps a person needs to see these groups of days four or three. He crosses them out. Bingo - it's done!

WHY was the McFlurry cup shape changed because of the hedgehogs?

In the past, the opening in the lid was much larger and more convenient. However, this convenience turned out to be a tragedy for the animals. Hedgehogs are big fans of McFlurry: they would lick off the leftover discarded ice cream.

But when they stuck their heads in the glass, they couldn't always get it back out, which led to trouble.
And after the case when as many as 10 hedgehogs in Scotland were taken to the clinic with the lid on their heads, McDonald's announced a redesign of the cup, which became safer for animals.🦔

WHY can't a person sleep standing up?

The human body is too flexible for a person to stand perfectly still, like a statue. In order to maintain an upright position he needs constant work of his muscles (mainly leg muscles), as well as muscle receptors and vestibular apparatus, which signal even the smallest deviations from the upright position.

The brain ensures the coordination of such work, but it cannot do this during sleep, so a person who falls asleep standing up will immediately fall down. But even if you don't let him fall, say, by clutching him in a crowd, he will only sleep for a few minutes.

During one of the phases of sleep (called REM sleep), most of the skeletal muscles are almost completely relaxed. A person in such a state will simply "flow" to the floor.

WHY is Churchill grumpy in his most famous photograph?

One of Churchill's most well-known photos of him, sullen and grumpy, was taken in 1941 after his speech to the Canadian House of Commons. When Churchill was brought into the room, he told the photographer he had two minutes and smoked a cigar.

The Prime Minister refused the photographer's request to put the cigar away. Then the photographer approached Churchill on the pretext of measuring the light level and took the cigar out of his mouth himself, and the Prime Minister's reaction to this insolence was just caught on camera.

But then Churchill smiled and allowed another picture to be taken, although this benign photo portrait is much less well known.

WHY does the brain consume the most oxygen and calories?

The brain contains up to 60% fat. It is the fattest human organ.

It makes up less than two percent of our body, but consumes about 20-30% of the calories in our food intake. Thus, constant malnutrition has a negative effect on a person's intellectual development.
Also the brain consumes 20% of all the oxygen entering the body.

For normal functioning of the brain, a person must breathe fresh air.

WHY do ice waves or bumps appear on the roads in winter?
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Ice bumps on the road are a consequence of double-wheeled buses and shuttle buses. They begin to form after warming, when there is a "snowy mess" on the road.
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Wheels in more or less random directions roll furrows, they break up into individual segments as they move and begin to grind away at the wheels.
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The wheel runs over such a bump, forms it when it stands. Then, when moving, the wheel usually still skips over, over this ice crust, and such grinding motions form the bumps.
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Another reason is when a wheel pushes snow in front of it, rolls a bump, then self-localizes in that spot, and stuffs the snow with subsequent wheels. This is how the bump is germinated and continues to grow.

WHY do cats' pupils narrow into vertical slits?

Narrowing the pupils into slits rather than dots gives cats finer control over how much light enters the eye. For an animal with an eye sensitive enough to see with almost no light, it is essential not to be blinded by bright sunlight, and narrowing the pupils into narrow slits gives a greater opportunity to reduce the incoming light and a more accurate ability to dose it.

The reason, however, why the slits into which the pupils narrow are in the vertical plane rather than the horizontal plane, is due to the fact that cats also use their eyelids to reduce the incoming light even further.

Using both of these slits, the vertical pupil and the horizontal eyelid, acting at the right angles one in relation to the other, the cat's eye is able to regulate the entry of light more finely than the eye of any other animal, without the risk of being blinded.

WHY are planets called as planets while stars are stars?

First and most importantly, stars are capable of emitting light and heat on their own, unlike planets, which can only reflect light rays falling on them from other luminaries, being inherently dark bodies.

Stars show much higher surface temperatures than any of the currently known planets. Their average surface temperatures range from 2,000 to 40,000 degrees, not to mention the layers closer to the center of the cosmic body, where temperatures may even reach millions of degrees.

On the surfaces of absolutely all stars, nuclear or thermonuclear reactions are bound to occur, followed by explosions. In turn, these reactions are not observed on the surfaces of planets, well, only in exceptional cases, and then only on nuclear planets and only super-weak nuclear reactions.

WHY shouldn't you kill domestic spiders?
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We all have spiders in our homes and there is nothing we can do about it. This fact might be unpleasant or even phobic to some people, but domestic spiders are completely harmless to humans. For sure, they are efficient killers in relation to domestic insects.
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Spiders act quickly and stealthily. Basement spiders prevent entry of woodlice and other moisture-loving insects into apartments. Spiders hiding in air vents prey on midges and mosquitoes. And those that live under the ceiling rid us of greasy buzzing flies.
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Moreover, domestic spiders are not aggressive towards humans and try their best to avoid meetings with us. In contrast to annoying insects, spiders do not need anything from us: they are our little helpers, "orderlies" of our homes. So even if you catch a spider at home and want to get rid of it - do not kill it, and just let it out on the street. The spider will find a new home and benefit someone.

WHY is a fir tree always green?

Scientists say that the needles are also a kind of "leaves". As you know, photosynthesis, that is, nutrition, takes place in the leaves. But the bigger the leaf, the more sunlight it needs and the longer this process takes. Accordingly, the smaller the leaf, the faster photosynthesis takes place.

Coniferous needles are very small in size. Therefore, they need less sunlight. They are rapidly photosynthesizing, which leads to the production of chlorophyll. And when there is chlorophyll, there is green!

Spruces have another secret to "evergreenness". Of course, a conifer cannot live their whole life with the same needles. In the spring of firs, pines and cedars cones appear, and needles slowly change, and in place of the old, dry, grow new - fresh ones. We never notice this change of needles, which is why it seems to us that the trees are always green.

WHY is hugging healthy?
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Hugging produces the hormone of happiness, oxytocin. It causes great effects on our body and mainly contributes to a good mood. In addition, oxytocin reduces stress.

That's because we feel a bond with another person and hence feel more confident in various everyday situations. It makes us less vulnerable to stress. Releasing oxytocin keeps us happy and relaxed.

It also helps us sleep better. A hug can make all anxiety disappear, make sleep easier and make sleep more restful. That's why it's worth a hug before bedtime.

WHY does the heart symbol appear that way?

There are several versions of its origin

- According to legends, the shape of the symbol heart is nothing other than an ivy leaf. Greek amphorae often used the ivy symbol for decoration.

- A pair of swans sailing toward each other forms the shape of a heart at the moment they touch. Swans are a symbol of love, loyalty and devotion, as a formed couple stays together for life, which is extremely rare in the animal world.

- During Antiquity, the ancient Greeks and Romans associated female beauty mainly with the shapes of women's bodies from the back. That is, the symbol of the heart is nothing more than a projection of a woman's buttocks on paper.

WHY is it hot when you go to bed fully under a blanket, cold without a blanket, and just perfect when you stick your foot out?

In general, since the blood vessels on the foot are so close to the skin, and there is a large flow of blood to the foot itself, the foot becomes a wonderful heat exchanger (a kind of radiator).

Hence, sticking out the foot discharges excess heat into the atmosphere, which the blanket prevents from losing, and brings the body to the optimum temperature for us.

WHY did the old telephones carry letters?

The Americans, the first to encounter seven-digit numbers, found a solution to the problem of memorizing (at the time it seemed difficult to remember seven-digit numbers) by using mnemonic rules - the first three digits were replaced by letters that began with a word.

For technical reasons, no number in America began with one. For historical reasons, zero was always used to call the telephonist. Thus, any American number could begin with any digit except 1 and 0.

Mnemonic rules were used in London and Paris until the mid-60s. The Americans first used the BBB-CTsC (three letters - four digits) scheme. Agree, it is much easier to keep the number TREmont 3106 in your memory than the corresponding number 873-3106.

As new words beginning with the right three letters became scarce, in 1930 New York, and in 1947...48 the rest of the cities were converted to the BBB-CTC scheme.

WHY is it better to bite your food in small pieces?
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If you can always take small bites out of your meals, you can prevent overeating and get rid of excess weight, since you will feel full quicker.
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When people eat large portions of food, they cannot adequately estimate how much they have eaten.

WHY is blood type B-negative the rarest?

The fourth positive type is much more common. The fourth group in general is a mystery, because it came from the fusion of two very different types, A and B. It is a young group, and people with it have a flexible immune system.

This group is unique in that it emerged not because of the influence of the external environment, but as a result of mixed marriages. It is worth mentioning that this group is the most biologically complex.
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Antigens sometimes make it similar to the second, and sometimes even to the third. Occasionally, it also happens that this rare group is something like a combination of both of these groups.

Thus, the fourth blood group is thought to have appeared later than all the others, about a thousand years ago, as a result of the mixing of Mongoloid and Indo-European.

WHY is there 12 months in a year?

Cause there are 12 new moons in the year. People used to count time using recurring natural phenomena. A year is the time from one flood to the other. Conversely, a month is the period from new moon to new moon, which is about 29.5 solar days.

➡ About 12 such intervals fit into a year, so 12 months were counted annually.

WHY do baby teeth fall out?

One important function of deciduous teeth is that they "point" to the molar teeth where they will erupt. If a baby tooth falls out prematurely, the permanent tooth "loses its bearings" and can grow crooked.

By the age of 6-7, these teeth will begin to erupt. This process is accompanied by the resorption of the roots of the baby teeth. This causes the baby teeth to loosen. When the shortened root can no longer hold the baby tooth in the hole, it falls out.