Whales are amazing creatures. Their ancestors appeared on Earth 55 million years ago - long before the appearance of the first man.
Despite the fact that whale hunting is prohibited by the laws of many countries, their destruction does not stop. For Russia, this problem is especially relevant - the seas of our country are home to dozens of species of whales, dolphins, and seals, many of which are endangered.
The most interesting facts from the life of whales are in the AiF.ru collection.
Photo: www.globallookpress.com
Whales are the largest animals in the world
On average, the length of a whale is from 22 to 27 meters, with females larger than males. The largest whale was caught in 1926: its length was 33 meters, and the animal weighed at least 150 tons. It is believed that blue whales were somewhat crushed as a result of predatory fishing, but in the past, when blue whales were more numerous, individuals up to 37 meters in length were found among them.
It is known that the average whale weighs as much as 2,700 people. The animal’s heart is the size of a car and weighs 600-700 kilos, and 8 thousand liters of blood are pumped through the whale’s vessels, the diameter of a water bucket. In addition, the blue whale is capable of producing the loudest sound of all living creatures - other whales are able to hear its low frequencies at a distance of more than 16,000 km.
Photo: www.globallookpress.com
Whales “hear” with their throats
Whales do not have the traditional hearing organs of animals - external ears. They hear through the lower jaw, from which sound travels to the middle and inner ear.
Since whales have poor eyesight and no sense of smell, hearing is the main sense for them, which helps them navigate underwater, communicate and get food. Therefore, ships and other noise made by people in the world's oceans cause a lot of inconvenience to whales.
A whale eats a million calories a day
For 8 months of the year, whales eat almost nothing and survive on accumulated fat. However, all summer they feed almost non-stop, absorbing up to three tons of food per day. The whale's diet mainly consists of algae and small crustaceans. Sometimes whales snack on small fish.
Photo: www.globallookpress.com
Whale tails are unique
Whale tails can be compared to human fingerprints. The furrow cuts, along with scars and spots of brown algae, create unique patterns on the whales' tails.
Whales and hippos shared common ancestors
The distant ancestors of whales were land animals that walked on four legs. Then they went to the ocean in search of more accessible and plentiful food. At first, the ancestors of whales - Pakicetus - hunted fish in shallow waters and returned to the shore to rest. But competition forced the animals to swim further and further into the depths of the ancient ocean, and the opportunity to return to land disappeared.
Molecular genetic data indicate that cetaceans are close relatives of artiodactyls, in particular hippopotamuses.
Whales can drown while sleeping
Whales can stay awake for three months if necessary.
And if they fall asleep, then only at a shallow depth near the surface of the water. Their weight, due to the high content of light adipose tissue in the body, slightly exceeds the specific gravity of water. Therefore, the sleeping whale sinks down very slowly. From time to time, the animal hits its tail in its sleep and rises to the surface. Then, after inhaling air, it slowly and passively sinks until the next blow with its tail.
Photo: www.globallookpress.com
Whales breathe oxygen
The blue whale inhales and exhales 1-4 times per minute when at rest, but can go without oxygen for two hours. Young whales breathe much more frequently than adults.
Whales inhale and exhale very quickly - almost simultaneously - due to the special structure of the respiratory tract. In 1 second, a blue whale inhales approximately 2 thousand liters of air; in total, the lungs of this giant can hold up to 14 cubic meters of air. While underwater, the blowhole was tightly closed with a valve.
A baby whale can reach 9 meters in length at birth. Mother's milk contains up to 50% fat, while it is rich in protein. Fat and protein make up half the weight of milk, making it very thick. During the day, the cub receives up to 90 liters of milk. By the age of one and a half years, it grows to 20 m in length and 45-50 tons of weight.
People believed that you could live in the stomach of a whale
In the old days there were many legends about how shipwrecked people were swallowed by whales and traveled for many months in the stomach of these animals.
In fact, they wouldn't even be able to get through the throat opening. The fact is that the diameter of a blue whale's pharynx does not exceed its navel (that is, the size of a saucer) or is slightly smaller than its eardrum (about the size of a small plate).
The only species of whale that a person can crawl into its throat is the sperm whale. However, its stomach is so acidic that it is simply impossible to survive in the belly of a whale.
Whales are talking
Whales that live a long time in captivity. For a long time this was considered a myth, but then scientists conducted an experiment on the beluga. The animal was trained to “speak” on command, put on a harness made of sensors and found out that the whale imitates human “speech” by sharply increasing the pressure in its nasal cavities and causing the phonic lips to vibrate - special formations in the nasopharynx, with the help of which many cetaceans make sounds .
Oscillations do not necessarily occur only where there is a separate mass and a separate spring. If the spring is massive enough, then it can cause vibrations itself, as soon as they are excited. If you push the spring sharply, as shown in Fig. 103, then it will begin to oscillate, as if waves will flow along it. Such waves that travel along an elastic body, causing it to alternately compress and stretch, are called longitudinal.
Rice. 103. Longitudinal waves in a spring
There are also transverse or standing waves. If you throw a stone into the water, then transverse waves will come from it (Fig. 104). A transverse wave is very clearly formed on a loosely stretched rope if it is pulled across (Fig. 105). This will seem strange, but a light wave, and even a radio wave, is precisely such a wave. We'll talk about this later, but for now let's see what kind of waves these are - sound waves.
Rice. 104. Standing waves on the surface of water
Rice. 105. Standing waves on a rope
Rice. 106. Longitudinal waves in an air column
Air is the same spring, only without individual turns, continuous. And if we treat the air in the same way as with the spring in Fig. 103, then it will also come into oscillatory motion (Fig. 106). The air has sufficient mass - about 1.3 kg/m3, it is elastic - under the piston it behaves like a real spring. Therefore, longitudinal waves will travel through it, just like through a spring.
The oscillation frequency, measured in hertz, is the reciprocal of the period. If the period of oscillation of a pendulum is 2 seconds (remember the meter-long pendulum?), then its frequency is 1/2 Hz. So, if air vibrations occur with a frequency from 16 to 20,000 Hz, then this is perceived as sound. Only very strong “listeners” can hear this entire frequency range. Usually heard from 20 to 18,000 Hz; 20 Hz is, perhaps, the sound of thunder, and 18,000 is the finest mosquito squeak.
In older people, the upper threshold of hearing sometimes drops to 6,000 Hz; in contrast, some children hear up to 22,000 Hz. And dogs can hear up to 38,000 Hz, that is, they are, perhaps, on par with infants.
Rice. 107. Bats hunt insects using ultrasound
They use this ability for “echolocation” when flying in the dark. It’s not for nothing that women are afraid of bats - thick, lush women’s hair is like a “sound pit” for sound; it does not reflect from them. And a deceived bat can, without understanding, grab the hair.
Sounds with high frequencies, above 20,000 Hz, are called ultrasounds. They scatter very weakly, go like a “beam” and therefore are very convenient for location. For this reason, not only bats, but also modern devices - sonars, use ultrasound for echolocation, especially in water (Fig. 108).
Rice. 108. Echolocation in water
Ultrasound is now widely used in technology and everyday life. Who doesn’t know ultrasonic washing machines – “tablets” or “balls” – they carefully wash fabrics, using extremely little energy.
Rice. 109. Scheme of ultrasonic flaw detection
In medicine, the human body is successfully “translated” with ultrasound, and this “transillumination” is not dangerous, like, for example, x-rays. Interestingly, ultrasound can also “illuminate” huge thicknesses of metal – 1 m or more, which is completely inaccessible to x-rays. Ultrasound propagates freely in metal and, reflected by inhomogeneities (voids, cavities, cracks), shows this. Devices - flaw detectors - are built on this principle, where ultrasonic signals from the emitter and passing through the metal are picked up by a probe sch and are transmitted to the receiver (Fig. 109).
Ultrasound has a detrimental effect on bacteria and even on cold-blooded animals - small fish and frogs die when irradiated with ultrasound in 1 - 2 minutes. But it is not dangerous for humans, otherwise pregnant women would not be “examined” with it. Now ultrasound is divided into three ranges: low frequencies - up to 105 Hz; medium - up to 105 - 107 Hz and high - up to 109 Hz. Elastic waves with frequencies of 109 – 1013 Hz are already called hypersound. And more often, it simply does not happen, because these waves in length already correspond to the interatomic distance in solids.
What happens when the sound frequency is less than 16 Hz? Such vibrations are called infrasound. Propagating well in water, infrasounds help whales and other marine animals navigate through the water. Hundreds of kilometers are no obstacle for infrasound. The effect of infrasound on humans is unique. Once in the theater, for a play about the Middle Ages, they ordered the famous physicist R. Wood (1868-1955) a huge organ pipe, it seems, 40 m long. The longer the pipe, the lower the sound it produces. Such a long pipe should have produced a sound that was no longer audible to the human ear. A sound wave 40 m long corresponds to a frequency of about 8 Hz, which is half the lower limit of audibility in height. And when they tried to use this pipe at the performance, it turned out to be an embarrassment. Although infrasound of this frequency was not audible, it came close to the so-called alpha rhythm of the human brain (5 - 7 Hz) and caused a feeling of fear and panic in people. The spectators fled, causing a stampede. In general, these frequencies are dangerous for humans. There is an opinion that the wind, reflected from long waves in the ocean, can generate infrasound, which has a detrimental effect on the human psyche. In this way, the mysterious disappearance of people from ships in the ocean, in particular in the Bermuda Triangle, is sometimes explained. They allegedly fell into panic and threw themselves out of the ships...
The volume or amplitude of sound vibrations is one of the most important characteristics of sound. Loudness is measured in decibels, in honor of the inventor of the telephone, physicist A. G. Bell (1847-1922). The weakest sound perceived by our ears is about 10 dB. Scream – 70 dB. The strongest clap of thunder is about 100 dB, and over 130 dB is already perceived as pain in the ears. What does this mean: the ticking of a wristwatch at a distance of 1 m is 30 dB, and at 4 times louder you already become deaf?
The fact is that the volume of sound here is not proportional to decibels. As we already know, 10 dB, or 1 B (it’s amazing, why was it necessary to introduce these decibels, when it’s simply much more convenient and shorter in whites?) is the weakest sound that can still be perceived by normal hearing. But the starting point, or 0 B, is taken to be a sound 10 times weaker. Maybe someone will hear! A sound at 2 B, or 20 dB, is no longer 2, but 100 times stronger than at 0 B, etc. That is, the number of bels measures the order of increase in sound volume. A sound of 10 B (or 100 dB) is 1010, or 10 billion, times louder than a threshold of 0 B! We estimate the scream of Aunt Sonya from Odessa at 7 B (70 dB), and twice as much - 14 B (140 dB) - this is the sound of an intercontinental missile launch, from which you can go deaf. So this sound is not 2 times, but 107, i.e. 10 million times, louder than Aunt Sonya’s cry!
And this entire unique “palette” of sounds - from 16 to 20,000 Hz, and from 1 B to sounds billions of times louder - is perceived and transmitted to the brain by our ear.
Rice. 110. Structure of the human ear:
1 – eardrum; 2 – articulated bones; 3 – oval window; 4 – main membrane
The ear is a complex sound-receiving apparatus that operates in an extremely wide range of frequencies and amplitudes. Sound waves reach our outer ear - its pinna, which is a horn that collects sound waves. Through the external auditory canal, sound waves reach the eardrum 1 (Fig. 110), which separates the outer ear from the middle ear. Under the influence of incoming waves, this membrane vibrates, performing forced vibrations with the frequency of the perceived sound. Vibrations of the eardrum through the system of articulated bones 2 (hammer, incus and stirrup) acting as a lever are transmitted to the so-called oval window 3, which closes the internal cavity of the ear labyrinth. The ear labyrinth, in the part where the auditory nerve endings that are sensitive to mechanical irritation lie, is filled with fluid - endolymph.
Inside there is the so-called main membrane 4, consisting of several thousand (about 4,500) fibers of various lengths, each tuned to a specific tone. Sound waves entering the inner ear cause vibrations in those fibers of the main membrane that are tuned to the frequencies contained in these waves.
Rice. 111. Sound “location” of a person
From the above description of auditory perception, it becomes clear why our ear is able to distinguish individual tones in a complex sound, such as a musical chord. It is of great importance that we have not one, but two identical ears. By assessing the strength of sound with our two ears, we can determine the direction in which it reaches us. When one of our ears is plugged, we cannot accurately determine where sounds are coming from. Listening with two ears, we can always turn our head so that we look in the direction of the sound source (Fig. 111).
But this is not always easy to do. If the sound is heard at a location that is equally distant from both ears, the direction of the sound source may be incorrectly determined.
In this case, it is useful not to immediately turn your face towards the rustle or sound, but, on the contrary, turn it to the side, thus pointing one of your ears at it. And by the difference in sound volume in the right and left ears, we can easily determine the direction from which the sound is coming. We sometimes instinctively do this when we listen.
Whales are amazing creatures, huge, really huge, but at the same time completely harmless. At least blue whales. The true scale of these giants is very difficult to imagine even from photographs - until you see them in person, you are unlikely to be able to feel the greatness of these creatures. The seasonal migration of whales is an amazing spectacle that attracts many tourists to some countries in Oceania.
- Blue whales are the largest animals that have ever lived on Earth. The body length of an adult whale of this species can reach 33 meters, and its weight can exceed 150 tons.
- Whales evolved from land-dwelling artiodactyl mammals, and this evolutionary leap occurred about 54 million years ago. Their huge bodies still have fur on them, they are warm-blooded and feed their offspring with milk.
- Whales are able to swim even in very cold water thanks to a thick layer of fat under their skin.
- During sleep, whales must periodically rise to the surface and inhale air, so at any given time, only half of their brain is asleep.
- In the past, people believed that the Earth rested on the backs of 3 large and 30 small whales.
- The tongue of a blue whale weighs 4 tons. It is so large that it can accommodate up to 50 people if desired.
- Whales can go 100 days without sleeping and not eating for up to 10 months.
- Newborn whales weigh several tons and have a body length of about 8 meters. Every day they drink 350-390 liters of mother's milk. The weight of six-month-old whales reaches 25 tons.
- The blood of whales is saturated with oxygen more than that of any other mammals. In a second, whales inhale 2000 liters of air, and they do this not with their mouths, but with a blowhole located at the back of their heads (see).
- During exhalation, bowhead whales release a fountain up to 6 meters high.
- The diameter of whale vessels is comparable to the diameter of buckets. Huge hearts pump 8,000 liters of blood through them.
- Whales are able to hold their breath for several hours.
- The blue whale's heart is the largest in the world, weighing about a ton. This is much larger than the heart of an elephant, the largest land creature (see).
- Whales can consume up to 8 million calories per day.
- Whales do not have ears; they hear using their lower jaw.
- Whales have poor eyesight and a completely absent sense of smell and taste.
- At great depths, fatty tears flow from the eyes of whales, protecting their eyes from salt and allowing them to see better.
- Whales and humans are the only mammals that sing songs. White whales make the most melodic sounds.
- Whales do not have vocal cords, but this does not prevent them from performing their songs for 30-40 minutes.
- Whale tails are unique, like human fingerprints - no two are alike in nature.
- Fin whales produce sounds of such low frequency that they are inaccessible to human hearing.
- Whales are capable of diving to depths of up to 3.5 kilometers. During a dive, the functioning of their internal organs slows down, for example, the heart beats only 10 times per minute.
- Whales don't drink seawater - they extract moisture from their food.
- Male whales have the largest sexual organ of all animals - its length reaches 3 meters and its diameter is 30 centimeters. Moreover, a whale egg is comparable in size to a mouse egg.
- In the past, narwhal whales have been pushed to the brink of extinction due to people's increased interest in their horns - in particular, scammers convinced their victims that they were unicorn horns.
- The lifespan of some whale species exceeds 100 years.
- Sperm whales are capable of making the deepest dives of any marine mammal - in search of food they descend to depths of up to 2 kilometers (see Fig.
- The most-most... The longest, heaviest, and loudest animals on our planet are whales. They are the ones with the biggest brains. Their length reaches 33 m, weight up to 150 tons. They make the longest and most distant migrations. Some of them may not sleep for three months and “fast” for two thirds of the year.
- The largest whale ever caught was a female caught off the South Scottish Islands. Its length from the fork of the caudal fin to the end of the snout was 33.27 m, and its weight was 176,792 kg.
- The blue whale is without a doubt the largest animal that has ever existed on our planet. The weight of an adult whale can be more than twice the weight of Brachiosaurus, the largest of the ancient dinosaurs (81,500 kg), and about thirty times the weight of a male African elephant.
- The blue whale's head is so wide that a full professional football team - about 50 people - can stand on its tongue. His heart is as big as a small car (Volkswagen Beetle). The heart of large blue whales weighs 600-700 kg, it needs to pump about 8 thousand liters of blood. The diameter of the dorsal aorta reaches the diameter of a bucket, and the lungs can hold up to 14 m3 of air. In one or two seconds, a whale inhales and exhales about 2000 liters of air. They dive with ease to great depths. If necessary, blue whales can remain underwater without breathing for 40 minutes. When a whale is about to dive, sometimes to a depth of over 1000 m, it stands upside down vertically in the water, so that only one caudal fin rises above the surface. It looks like a sail. Whales do not have external ears. Instead, they receive sound through their lower jaw. Sound is conducted from the jaw through the socket to the middle and inner ears.
- An adult blue whale consumes about a million calories a day, which equates to 1 ton of krill, the small, shrimp-like crustacean that forms the bulk of its diet.
- The blue whale is accustomed to roaming the world's oceans, traveling alone, occasionally in pairs, and can live up to 120 years. Whales are the only mammal other than humans that... sing. Many of them make low cooing sounds, and humpback and right whales sing “songs” - a series of different sounds repeated in a certain sequence. At first it was believed that only males sing, but there is evidence that females sing songs to their babies.
- Pregnancy lasts about 11 months. The calf is born 7.6 m long and weighs 2-3 tons, although the egg of a female blue whale is the same in size as that of a mouse. During the day he gains 80-100 kg in weight and 2-3 cm in length, drinking approximately 380 liters of mother's milk. Females feed them milk for about 7 months. During this period, the cub grows up to 16 m and has a mass of 23 tons. Over 7 months of feeding, the female’s mammary glands secrete so much milk that its amount is equal to the weight of her own body.
- Baleen are horny plates on the upper jaw of toothless whales (up to 800 pieces), which were and are used in the manufacture of corsets and various pads to maintain the shape of clothing. A Baroque corset required a whole kilogram of whalebone. This material was in such demand that in Holland in 1772 a company was founded that supplied whalebone to all European countries.
- Whales easily distinguish each other in a school. But for a person this is a difficult task, because he sees them only for moments. How can you learn to identify whales so that you can follow them? Scientists believe: by tails. Biologists have discovered that whale tails are as individual as human fingerprints. Cuts and grooves are easily visible on them, scars from killer whale bites, and spots of brown algae create a unique pattern.
- Once upon a time, blue whales roamed all the oceans of the world; and it is estimated that in Antarctica alone there were up to 250,000 of these creatures. However, in recent years, ruthless fishing has left less than 1% of the above figure. It is very difficult to determine the total number of these huge animals, so the size of the Antarctic blue whale population, according to modern estimates, ranges from several hundred to 11,000. But whatever the exact figure, it in any case appears dangerously low compared to previously existing numbers.
Now you know more :)
To the question Why do whales hear each other at a distance of thousands of kilometers? given by the author Landrail the best answer is The hearing organs are greatly modified. The auricle is missing. The auditory canal is narrowed and opens behind the eye with a small opening; Apparently, it serves as a separate sensory organ that perceives changes in pressure. The eardrum is curved outward (baleen whales) or inward (toothed whales). Cetaceans perceive sound through the bones of the skull and lower jaw, the posterior end of which is close to the area of the inner ear and innervated by a branch of the trigeminal nerve. The structure of the inner ear in cetaceans is very complex, with an enlarged cochlea. Sound for aquatic organisms is the most important source of information, since sound vibrations travel 5 times faster in water than in air. Cetaceans are able to detect sound waves in the range from 150 Hz to ultrasonic vibrations at 120-140 kHz. The hearing of toothed whales is most acute; in baleen whales it is worse compared to land mammals.
Cetaceans produce sound signals in the same frequencies that they perceive themselves. Since they do not have vocal cords, sounds are produced by vibration of the “sound lips” (toothed whales) or by the larynx and pharynx (baleen whales). The communication sounds produced by cetaceans are many and varied; there are special signals of feeding, anxiety, fear, mating, pain, etc. Some cetaceans from the suborder Odontoceti, like bats, are capable of directional echolocation. They have developed a special echolocation apparatus, consisting of a fat pad and a concave front surface of the skull, which act as a sound lens and reflector, concentrating the emitted ultrasonic signals and directing them to an object in the form of a sound beam.
Whale songs are sounds made by cetaceans to communicate. The word "songs" is used to emphasize the repetitive and melodic nature of sounds, reminiscent of human singing.
The use of sounds as the main channel of communication is due to the fact that in an aquatic environment visibility can be limited, and odors spread much more slowly than in air.
The most complex songs of humpback whales and some toothless whales are believed to be used in mating displays. Simpler signals are used year-round and perhaps serve for everyday communication and navigation. Toothed whales (including killer whales) use their sounds for echolocation.
Alexander Maly
Guru
(3735)
Whales on our planet have one of the best and highest quality hearing. It's safe to say that a whale's hearing is perfect. They capture sounds through the throat, and then through a special channel the sound reaches the inner ear.
Answer from 22 answers[guru]
Hello! Here is a selection of topics with answers to your question: Why do whales hear each other at a distance of thousands of kilometers?
Answer from make christ[active]
They vibrate the nasal septum and the vibration travels much further than sound, and even more so under water
Answer from . : KZ: .[active]
so that people like you would ask why)))
Answer from MoBunny[guru]
All cetaceans lack vocal cords, so these animals
cannot make sounds in the usual way. But with the help of nasal vibrations
partitions they are capable of emitting about 30 different sound signals
and communicate with each other in such an unusual way.
Baleen whales have poor hearing, much worse than land mammals.
But toothed whales have very fine hearing, capable of detecting even
ultrasonic vibrations. Toothed whales navigate underwater
and find prey using echolocation - sending ultrasonic
signals and receiving the reflected pulse. There is a hypothesis according to which
toothed whales can communicate with each other from different ends of the ocean!
