WHY do birds migrate?
For a long time, there was only one explanation for birds' migrations: they are cold in winter and need a change of climate. Yet feathers can do a pretty good job of protecting birds from the cold. For example, a canary capable of surviving the cold up to -45 degrees Celsius if it has enough food.
Now it is believed that birds fly away to warmer areas in winter from the winter lack of food. Birds use up the energy they get from food very quickly, which means they need to eat often and a lot.
So when the ground freezes and food is hard to find, especially for insectivorous birds, many of them head south.
For a long time, there was only one explanation for birds' migrations: they are cold in winter and need a change of climate. Yet feathers can do a pretty good job of protecting birds from the cold. For example, a canary capable of surviving the cold up to -45 degrees Celsius if it has enough food.
Now it is believed that birds fly away to warmer areas in winter from the winter lack of food. Birds use up the energy they get from food very quickly, which means they need to eat often and a lot.
So when the ground freezes and food is hard to find, especially for insectivorous birds, many of them head south.
WHY do bees make honey?
Honey is vital to bee nutrition, especially in the winter.
To make honey, bees collect nectar from flowers. Since nectar contains a lot of water, bees have to work hard to dry it out. Also, bees add enzymes from their own bodies to the honey to turn the nectar into food and keep it from spoiling.
Honey is stored in the honeycomb for maturation. During ripening, the young bees transfer nectar from one cell to another several times, each time adding their own saliva. This honey is used as food by the bees as needed.
Honey is vital to bee nutrition, especially in the winter.
To make honey, bees collect nectar from flowers. Since nectar contains a lot of water, bees have to work hard to dry it out. Also, bees add enzymes from their own bodies to the honey to turn the nectar into food and keep it from spoiling.
Honey is stored in the honeycomb for maturation. During ripening, the young bees transfer nectar from one cell to another several times, each time adding their own saliva. This honey is used as food by the bees as needed.
WHY does a toucan have a big beak?
Despite its impressive size, the beak is not much of a burden for the bird, as it is very light due to the air cavities inside it: its structure resembles that of frozen foam.
Ornithologists agree that the toucan needs its long beak to get berries from the ends of thin twigs, which can't bear the bird's half-kilogram weight.
Despite its impressive size, the beak is not much of a burden for the bird, as it is very light due to the air cavities inside it: its structure resembles that of frozen foam.
Ornithologists agree that the toucan needs its long beak to get berries from the ends of thin twigs, which can't bear the bird's half-kilogram weight.
WHY are lightning rods used?
Lightning is a highly strong electrical spark that travels several kilometers in the sky in a matter of seconds. This spark makes the air hot and causes an explosion.
A single stroke of lightning can incinerate a tree and start a fire. But long ago people thought of a way to protect themselves and their homes from this danger. They invented the lightning rod — a metal rod, one end of which rises above the roofs of houses and the other end of which is connected to the ground with a wire.
Lightning finds the shortest route: it strikes the rod and, without hurting anyone, escapes through the wire into the ground.
Lightning is a highly strong electrical spark that travels several kilometers in the sky in a matter of seconds. This spark makes the air hot and causes an explosion.
A single stroke of lightning can incinerate a tree and start a fire. But long ago people thought of a way to protect themselves and their homes from this danger. They invented the lightning rod — a metal rod, one end of which rises above the roofs of houses and the other end of which is connected to the ground with a wire.
Lightning finds the shortest route: it strikes the rod and, without hurting anyone, escapes through the wire into the ground.
WHY are sea currents affecting the weather?
The World Ocean plays a special role in creating the climate. Huge amounts of water accumulate here. Evaporation, heating and cooling have a permanent effect on cloudiness and winds.
Another important fact to consider is that the water of the oceans and seas is in constant motion: the upper and lower layers mix, strong currents move cold or warm water over vast distances, affecting the nature of the weather.
The World Ocean plays a special role in creating the climate. Huge amounts of water accumulate here. Evaporation, heating and cooling have a permanent effect on cloudiness and winds.
Another important fact to consider is that the water of the oceans and seas is in constant motion: the upper and lower layers mix, strong currents move cold or warm water over vast distances, affecting the nature of the weather.
WHY do amphibians not live in salt water?
Since amphibians' lungs do not fully supply them with oxygen, skin respiration, which requires a moist, thin skin, plays a major role.
Amphibians are highly sensitive to the absence of table salt in soil and water, which is specifically detrimental to the development of their eggs and larvae.
The concentration of salt in the skin cells of amphibians is less than in seawater.
And if an amphibian gets into seawater, then water from the skin cells will begin to flow out freely, as their skin is extremely permeable to water.
Since amphibians' lungs do not fully supply them with oxygen, skin respiration, which requires a moist, thin skin, plays a major role.
Amphibians are highly sensitive to the absence of table salt in soil and water, which is specifically detrimental to the development of their eggs and larvae.
The concentration of salt in the skin cells of amphibians is less than in seawater.
And if an amphibian gets into seawater, then water from the skin cells will begin to flow out freely, as their skin is extremely permeable to water.
WHY do ozone holes appear?
The ozone layer is located in the stratosphere about 25 kilometers above the Earth's surface. It protects our planet from the most active cosmic rays, which would kill all life on the planet without it.
Ozone holes are places where the layer is depleted. Nevertheless, more intense ultraviolet rays reach the planet through these gaps.
Again, humans are to blame for the ozone holes. By producing large quantities of chemicals, primarily chlorinated and fluorinated hydrocarbons that can slowly destroy ozone as they rise into the atmosphere.
The ozone layer is located in the stratosphere about 25 kilometers above the Earth's surface. It protects our planet from the most active cosmic rays, which would kill all life on the planet without it.
Ozone holes are places where the layer is depleted. Nevertheless, more intense ultraviolet rays reach the planet through these gaps.
Again, humans are to blame for the ozone holes. By producing large quantities of chemicals, primarily chlorinated and fluorinated hydrocarbons that can slowly destroy ozone as they rise into the atmosphere.
WHY do frogs squawk?
Only male frogs make squawking sounds. Quacking is a way to attract females during the mating season.
In order to make a squawking sound, a frog takes a deep breath, closes its nostrils and mouth, and presses air from its lungs to its mouth and back again. Passing through the vocal cords, the air stream touches them, they begin to vibrate, and a quacking sound is heard.
Only male frogs make squawking sounds. Quacking is a way to attract females during the mating season.
In order to make a squawking sound, a frog takes a deep breath, closes its nostrils and mouth, and presses air from its lungs to its mouth and back again. Passing through the vocal cords, the air stream touches them, they begin to vibrate, and a quacking sound is heard.
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WHY would a person not recognize their own voice on a recording?
Due to the superimposition of the two timbres.
A person's own voice normally reaches the ear in two ways: through the air and through the tissues of the body, primarily the bones. Owing to the different speed of sound in these media, the same original sound takes on a differing timbre.
In this case we hear a superposition of the "air" and "bone" timbres of the voice. And when listening to a recording, we hear only the "airy" component.
Due to the superimposition of the two timbres.
A person's own voice normally reaches the ear in two ways: through the air and through the tissues of the body, primarily the bones. Owing to the different speed of sound in these media, the same original sound takes on a differing timbre.
In this case we hear a superposition of the "air" and "bone" timbres of the voice. And when listening to a recording, we hear only the "airy" component.
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WHY amnesiacs do not forget their language and can speak?
The formation of speech occurs in a person up to 6 years old. Thus, the speech skill constitutes the core of the personality and reliably protected: The areas responsible for it are located deep, at the base of the parietal lobe of the brain.
Moreover, when it comes to speech, the two hemispheres are capable of duplicating each other in severe trauma. If one hemisphere suffers, the other takes over vital functions, including speech. In contrast, the area responsible for memory is located almost on the very surface of the cortex, it is less protected, so it is disconnected in case of amnesia.
The formation of speech occurs in a person up to 6 years old. Thus, the speech skill constitutes the core of the personality and reliably protected: The areas responsible for it are located deep, at the base of the parietal lobe of the brain.
Moreover, when it comes to speech, the two hemispheres are capable of duplicating each other in severe trauma. If one hemisphere suffers, the other takes over vital functions, including speech. In contrast, the area responsible for memory is located almost on the very surface of the cortex, it is less protected, so it is disconnected in case of amnesia.
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WHY is one of the proteins in the human eye named after Pikachu?
In 2008, Japanese scientists from the Osaka Institute of Biological Sciences discovered a protein playing a crucial role in transmitting signals between the ribbon synapses of the human eye's photoreceptors and dendrites.
They named the protein Pikachurin, after the lightning-speed movement and electrical abilities of the Pokémon Pikachu.
In 2008, Japanese scientists from the Osaka Institute of Biological Sciences discovered a protein playing a crucial role in transmitting signals between the ribbon synapses of the human eye's photoreceptors and dendrites.
They named the protein Pikachurin, after the lightning-speed movement and electrical abilities of the Pokémon Pikachu.
WHY does an LED bulb glow in the dark?
It is due to the fact that the lighting element, which is installed in the switching device, closes the circuit, accordingly passing a small current. It charges and allows the light bulb to glow when it is off.
Is this glow dangerous? No danger of this problem for wiring, but the life of the LED light bulbs will be markedly reduced if they are constantly flashing or glow dimly.
It is due to the fact that the lighting element, which is installed in the switching device, closes the circuit, accordingly passing a small current. It charges and allows the light bulb to glow when it is off.
Is this glow dangerous? No danger of this problem for wiring, but the life of the LED light bulbs will be markedly reduced if they are constantly flashing or glow dimly.
WHY do fireflies glow?
Bioluminescence for fireflies is a means of intersex communication.
Not only do the insects signal their location, but they also distinguish their partner by a specific flicker frequency.
Tropical and North American firefly species sometimes perform entire choral serenades for their mates, simultaneously flaring up and fading out as a flock. A pack of females responds to them with the same light music.
Bioluminescence for fireflies is a means of intersex communication.
Not only do the insects signal their location, but they also distinguish their partner by a specific flicker frequency.
Tropical and North American firefly species sometimes perform entire choral serenades for their mates, simultaneously flaring up and fading out as a flock. A pack of females responds to them with the same light music.
WHY does rubbing alcohol burn skin?
The reason is not that alcohol destroys bacteria, but due to the reaction it causes in the body.
When in contact with the skin, it irritates the receptors responsible for sensing temperature. Normally they are activated by elevated readings, but alcohol lowers their threshold of sensitivity to body temperature. The receptors feel that the body is being exposed to excessive temperatures and transmit a feeling of pain to the brain.
The reason is not that alcohol destroys bacteria, but due to the reaction it causes in the body.
When in contact with the skin, it irritates the receptors responsible for sensing temperature. Normally they are activated by elevated readings, but alcohol lowers their threshold of sensitivity to body temperature. The receptors feel that the body is being exposed to excessive temperatures and transmit a feeling of pain to the brain.
WHY are we getting air blown around when enter stores?
The main purpose of this action is to keep the air in the building at a constant temperature, preventing outdoor exposure at the entrance.
This practice is especially useful if the doors of the establishment must remain open. In this way, the flow of warm air in winter and cold air in summer protects the internal temperature of the establishment from drastic fluctuations. In addition, insects and debris from the street cannot get through the "air door".
The main purpose of this action is to keep the air in the building at a constant temperature, preventing outdoor exposure at the entrance.
This practice is especially useful if the doors of the establishment must remain open. In this way, the flow of warm air in winter and cold air in summer protects the internal temperature of the establishment from drastic fluctuations. In addition, insects and debris from the street cannot get through the "air door".
WHY does a boomerang return?
The boomerang's shape and the way it is thrown is such that in flight it is subjected to an aerodynamic force which is directed perpendicular to its trajectory.
Due to this, the boomerang does not fly straight ahead, but, like a curved ball, takes to the side and returns approximately along a circular trajectory.
Unless, of course, it hits its target on the way. But there are also such boomerangs, which fly straight ahead and use aerodynamics to increase the flight range.
The boomerang's shape and the way it is thrown is such that in flight it is subjected to an aerodynamic force which is directed perpendicular to its trajectory.
Due to this, the boomerang does not fly straight ahead, but, like a curved ball, takes to the side and returns approximately along a circular trajectory.
Unless, of course, it hits its target on the way. But there are also such boomerangs, which fly straight ahead and use aerodynamics to increase the flight range.
WHY are dreams so hard to remember?
The conditions of the brain during sleep do not allow the dream to be transferred to long-term memory upon awakening.
In addition, a lack of the hormone noradrenaline, which is responsible for long-term memory, also plays a role.
Another reason could be that neurons from the hippocampus do not work properly during the REM sleep phase, which prevents them from transferring information to other neurons, delivering sleep never stored in memory.
The conditions of the brain during sleep do not allow the dream to be transferred to long-term memory upon awakening.
In addition, a lack of the hormone noradrenaline, which is responsible for long-term memory, also plays a role.
Another reason could be that neurons from the hippocampus do not work properly during the REM sleep phase, which prevents them from transferring information to other neurons, delivering sleep never stored in memory.
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WHY do dogs drink toilet water?
Dogs are scavengers by nature. It's in their genes and has been for thousands of years.
A dog sees the world differently than a human. A dog's value system and its understanding of right and wrong is radically various from that of humans. For them, drinking from the toilet is not at all disgusting, but rather natural. The logic is simple: if you see a source of cool water, drink it.
The water in the toilet is always cool and clean, unless, of course, the toilet bowl itself is dirty. Cold, fresh water is preferable to room temperature water. In addition, the water we pour for our pets can sit in the bowl for several hours, and bits of food can accumulate there.
Also, the water in a metal or plastic bowl may have a tang of the material, making it less appealing to the pet.
Dogs are scavengers by nature. It's in their genes and has been for thousands of years.
A dog sees the world differently than a human. A dog's value system and its understanding of right and wrong is radically various from that of humans. For them, drinking from the toilet is not at all disgusting, but rather natural. The logic is simple: if you see a source of cool water, drink it.
The water in the toilet is always cool and clean, unless, of course, the toilet bowl itself is dirty. Cold, fresh water is preferable to room temperature water. In addition, the water we pour for our pets can sit in the bowl for several hours, and bits of food can accumulate there.
Also, the water in a metal or plastic bowl may have a tang of the material, making it less appealing to the pet.
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