Why?

2023-06-27 14:00:12 WHY are ladybugs sold by weight?

Beetles and their larvae are predators, and they are extremely voracious. The seven-point ladybug we know kills up to 150 aphids a day, while the smaller species kill up to 60. As larvae, the beetles destroy up to 800 aphids during the whole period and more than 4,000 aphids during the whole life cycle.

When touched, coccinellids secrete droplets of caustic orange hemolymph from their knee joints, burning the throat of their attackers and rendering them inedible to most insectivores and vertebrates. Even tarantulas leave ladybugs untouched.

Ladybugs are highly useful in pest control, so the bugs collected in the fall are sold by weight to gardeners and vegetable growers reluctant to use chemicals for this purpose. Открыть/Комментировать

2023-06-26 21:00:08 WHY is red wine so widely admired?

Red wine, mostly dry, has long been considered not only a noble drink pleasing the soul, but also a cure for bodily ailments. Its benefits for the body are undeniable, but be sure to remember about its moderate use, namely, according to medics, not more than 250 grams a day.

The fact that dry red wine significantly reduces the risk of heart disease has already been proven. The presence of red pigments in the shell of grape berries contributes to this. Such pigments belong to the group of highly powerful natural antioxidants.

It was also found that the organic substance tannin in red wine prevents the formation of blood clots. Открыть/Комментировать

2023-06-26 14:00:14 WHY do people with hearing loss put the palm of their hand to their ear?

The inside of the palm acts as a concave mirror that concentrates sound waves coming from the front. The back side weakens the noises coming from behind.

However, such an effect is only clearly expressed for sounds with a frequency of more than 800 Hz, due to the small size of the palm. It is much higher than the human voice, but the palm enhances overtones with a frequency up to several kilohertz, which may slightly improve speech perception.

Still, if your hand is constantly reaching for your ear, better consult a doctor. Открыть/Комментировать

2023-06-25 21:00:08 WHY are people trying to humiliate others insecure about themselves?

The desire to offend, insult, or humiliate another person does not come from a good life. The scandalous lady on the bus, the man calling his wife fat and stupid, the children at school bullying a classmate - all of them are absolutely self-doubting and are trying to increase their sense of importance through ostentatious aggression.

At the same time, these people are sincerely convinced that their negative attitude toward others has nothing to do with their inner sense of self. Открыть/Комментировать

2023-06-25 14:00:12 WHY are planets, satellites, and stars round while asteroids are not?

Small asteroids have too weak gravity to deform rocks, so objects up to a few hundred kilometers in size have an irregular shape.

The matter of a star or planet tends to be at the same distance from its own center of gravity. The reason here is the same as why the water in a pond is set at the same level, rather than rising with a hump. Открыть/Комментировать

2023-06-24 21:00:08 WHY don't we remember being born?

A group of scientists believes that the loss of infant memories is related to the active process of new cell formation-neurogenesis. According to Paul Frankland, recent research has proven that neurogenesis can both shape and erase information about the past.

We don't remember the first years of life due to the fact that this is the most active period of neurogenesis. Then neurons begin to reproduce at a slower rate and cannot process some of the childhood memories. Открыть/Комментировать

2023-06-24 14:00:12 WHY and how can one bite the tongue?

A powerful artery runs in the root of the tongue, in the lower part, and by biting it, in case of failure to provide some assistance, you can die of blood loss. True, death would not be quick. To do this, one must know the place of biting the tongue and master the technique of powerful strokes (bites).

As for the technical performance of this procedure, obviously, it will not work without special psychological and physical training. Japanese warriors were famous for such special training.

The Japanese, who were captured, would bite off their tongues and die without waiting for torture. When capturing Japanese warriors, they sometimes used a special device that was put over their mouths to prevent the captive from biting off his tongue. Открыть/Комментировать

2023-06-23 21:00:11 WHY do cats wallow in dust?

Wild cats, forced to find their own food, had to constantly worry about camouflage. Their prey, small rodents, wields a good sense of smell, thanks to which they can detect the approach of the hunter.

Rolling on the ground, the cat tries to blunt the vigilance of its potential prey by minimizing its own scent and masking it with the smell of plant pollen and mineral particles contained in dust. Although a domesticated cat no longer needs a disguise, instinct makes the animal behave as its ancestors did when they hunted game in ancient Egypt or Africa.

But we cannot rule out the possibility that whenever your pet defiantly rolls down on its back, showing its adorable tummy, it does it solely to attract attention. It is a peculiar request of your pet to give her a few minutes, to caress her, to play with her. Открыть/Комментировать

2023-05-22 14:00:12 WHY do museums keep some paintings under glass while others don't?

Traditionally, oil paintings are exhibited without glass. The painting is normally coated with a transparent varnish, which makes it resistant to exposure and allows for wet cleaning. Graphics are usually displayed under glass, as pencil, watercolor, ink and pastel are easily damaged and almost impossible to clean.

In some cases, oil paintings are also protected by glass. For example, against fading due to ultraviolet light or when cracks in the paint prevent wet cleaning, as well as in cases of special value and threats of vandalism. Открыть/Комментировать

2023-05-21 21:00:11 WHY is the fruit green at first and then changes color?

Photosynthesis continues in the newly formed fruit, meaning the chlorophyll pigment, which has a green color, is present. As the fruit matures, the chlorophyll breaks down and the synthesis of pigments of other colors intensifies in the fruit. This attracts animals, which contribute to the spread of the seeds.

The contrasting color against the green foliage serves to encourage animals to find the ripe fruits without touching the unripe ones. Открыть/Комментировать