Adrian Bates
Becoming a prince is, of course, a fairy tale. But doesn't the frog demonstrate evolution that occurs throughout its own life cycle? From a fish-like tadpole (which has full gills), the “little frog” quickly “changes” to lead a whole new way of life! Its mouth expands, its tail dissolves, a “rubber-like” tongue is formed for catching flies, nostrils are also formed, and its bulging eyes can turn in all directions. Eventually, when the lungs are fully mature and four legs grow, the modified tadpole celebrates its adulthood and jumps out of the water to live on land.
This amazing transformation (called metamorphosis) is much more than just an external change. There is a radical remodeling of almost all systems and organs of the body. For example, the nervous system must be completely "rewired and rewired" for new or reprogrammed patterns of eyes, ears, paws, tongue, and so on to work. The same changes must occur at the biochemical level of the body. The hemoglobin in the blood changes, as does the photochromic material in the eyes, not to mention a huge number of other changes. Even excretory system changes in order to meet the new living conditions of the frog.
At this extremely miniature level we find not only complete drawing future frog, but also a fully functioning factory with all the mechanisms and equipment that help turn the plan into reality.
Biologists shake their heads at the complexity of this tadpole transformation that occurs in ponds. Frog, "sunbathing" on the leaf of a floating water lily, is the amazing result of numerous changes occurring one after another with amazing precision in one tadpole. The opening ceremony Olympic Games simply pales in comparison to the “choreography” of the transformation of a tadpole into a frog. For example, life certainly becomes difficult for a tadpole when its tail disappears and its legs have not yet grown. The same goes for him internal organs, bones, nerves, biochemistry and so on. Any wrong step can cause the entire huge transformation process to stop... and lead (from the tadpole's point of view) to some rather unfortunate results!
Each step is necessary for the next
Over the course of many years research work multiple layers of processes have been discovered that are necessary to complete this “life change.” For example, the process of tail disappearance is a highly organized, programmed micro-logistics process. At the beginning, the tadpole slows down the formation of tail muscle cells. Next, it produces a number of special enzymes that dissolve tail cells. These enzymes are then selected at the right time and introduced into all the different types of tail cells. And finally, wandering macrophages settle on the tail cells that have completed their growth for microscopic “eating,” disassembling and assembling the remaining structures and nutrients for their reuse as building materials and energy in other parts of the body. (That is, the tail is absorbed by the body rather than discarded).
"Change" does not mean "evolution"
So how plausible is the statement about “ evolution in action"? Is tadpole metamorphosis a clear example of evolution?
Incredibly complex command system
The unusually complex coding information in DNA that helps a tadpole develop into frog, clearly indicates the Supreme Intelligence that created such a design. Such coding cannot be formed naturally - it demonstrates a consciously created final product.
Nothing like this! Even though the tadpole may look like a “fish”, from the very first day of its life it is a frog. Everything that a tadpole needs to change (i.e. all the genetic information, plans and methods) already concluded in the basic DNA code in the nuclei of tadpole cells. On this extremely miniature level we discover not only a complete blueprint of the future frog, but also a fully functioning factory with all the machinery and equipment that helps turn the plan into reality.
This embedded information is the main difference between the evolutionary tale (in which a fish evolves into an amphibian) and the real world (in which a tadpole becomes a frog). From the very first day it is born from an egg, the tadpole is already equipped with a full set of “do it yourself transformation” tools necessary to transform into a frog on its own. In contrast, fish only have the information to “produce”... fish! In its genes, a fish does not contain information about how to turn into an amphibian animal and has no way to obtain such information. I really doubt there is a single clear example of evolutionary mechanisms adding new information to the genetic blueprint of any animal.
Therefore, the metamorphosis of a tadpole does not in any way testify in favor of evolution - it is rather a clear example self made God the Creator.
Wood frog tadpoles are not born knowing which predators they should be afraid of and must learn this throughout their lives. Tadpoles that have been taught to fear one of the predators (the fire-bellied newt) also begin to fear other amphibians, which can be interpreted as a kind of “ability to generalize.” Moreover, the stronger the fear of newts, the wider the range of potential predators that causes a characteristic fear reaction in tadpoles.
Some animals have an innate knowledge of which predators they need to watch out for. Others are born without this knowledge and must acquire it throughout their lives. It would seem that the first option is much more reliable and safer. However, this is only true for those species of prey that live in more or less constant conditions and are threatened by the same predators from generation to generation. If the environment of a given prey species changes frequently in unpredictable ways, developing an innate fear of certain types of predators may be less beneficial than a general ability to learn—even though such learning carries enormous risks.
Many species of frogs lay their eggs in a variety of bodies of water, from small, ephemeral puddles to large lakes. In different bodies of water, tadpoles are threatened by different predators. Tadpoles react to danger by decreasing motor activity: They freeze or simply start swimming more slowly to attract less attention to themselves. If a tadpole is afraid of all predators indiscriminately - including those that do not feed on tadpoles in a given reservoir - it will freeze all the time and will have less time to search for food. In such a situation, an innate fear of all types of potential enemies would be more harmful than beneficial for the tadpoles. The behavior of tadpoles (and other prey animals) must maintain a delicate balance between the magnitude of the danger and the intensity of the reaction to it. If the degree of danger posed by the same predator species varies greatly depending on conditions, lifetime learning becomes a more optimal strategy than the development of innate fear.
Little is known yet about the specific mechanisms underlying prey learning to fear predators. Of the established facts, two are the most interesting. Firstly, it has been shown that such learning occurs very quickly - usually a predator only needs to scare the prey once for it to develop a stable fear of this type of predator. In some cases, one can assume the existence of certain innate psychological “blanks” or matrices, that is, an innate predisposition to quickly develop fear of certain types of stimuli. Secondly, the phenomenon of generalization (generalization) in recognizing predators was discovered. This means that animals that have learned to fear a particular predator (in an experiment, a doll can act as a predator) often begin to experience fear also of other objects that are similar to the predator they know in appearance or smell.
In an article by Canadian biologists published on the journal’s website Behavioral Ecology and Sociobiology, interesting experiments are described in which for the first time the ability to “generalize the image of a predator” was demonstrated in the larvae of tailless amphibians.
The authors mention only three earlier studies that examined this phenomenon. If they haven't missed anything, their work is the fourth in the field. The first study was carried out on wallabies Macropus eugenii. It turned out that wallabies are not naturally afraid of foxes, cats, or goats. If you teach a wallaby to be afraid of foxes, then they automatically begin to be afraid of cats (but not goats). Another study found that wild black-tailed deer Odocoileus hemionus columbianus They are afraid not only of pumas, which pose a real threat to them in nature, but also of jaguars, which they never meet. These experiments did not use live predators, but their models, that is, they were talking about recognizing a predator only by its appearance, and not by smell or behavior.
The third study was conducted by the authors of the article discussed in 2007-2008. on a fish Pimephales promelas(black fathead, see fathead minnow). The fish were trained to fear the smell of a species of trout. It turned out that the generalization of the image of a predator occurs only if a very high degree of risk is associated with this predator. If the fish perceives this type of trout as moderately dangerous, then the smell of other types of trout does not frighten it. If the fish were made to understand that this trout was extremely dangerous, then they also began to be afraid of the smell of other trout (but not pikes or chukuchans).
In a new experiment, tadpoles of the American wood frog were chosen as the object. Rana sylvatica(see wood frog). In their previous works, the authors showed that these tadpoles do not have an innate fear of tailed amphibians (newts, salamanders), which are their natural enemies.
Wood frog eggs were placed in a large aquarium with clean water, where there were all the necessary conditions for the development of tadpoles, but there were no predators (the authors took all possible measures to ensure that there was no smell of predators there). When the tadpoles hatched and reached two weeks of age, the researchers divided them into three groups and began training. The training was carried out as follows.
Each tadpole was placed in a separate half-liter jar and allowed to get used to the new environment. Then 10 ml of water with the smell of fire-bellied newt was added to the jar Cynops pyrrhogaster. It was water from a two-liter container in which six newts lived for 24 hours. At the same time, another 5 ml of water with the “smell of danger” was added to the jar. The recipe for preparing this potion is reminiscent of the methods of medieval witches or alchemists: one tadpole was ground in a small mortar, the resulting pulp was diluted with water in an amount of 5 or 20 ml, the water was then carefully filtered to remove tissue fragments. The smell of a crushed tadpole is an unconditional frightening stimulus, that is, tadpoles from birth know that this smell signals danger.
Tadpoles from the first group received the “smell of danger” in a high concentration (1 crushed tadpole per 5 ml of water), the second group received a four times smaller dose. Finally, the tadpoles of the third (control) group received 5 ml of clean water.
The idea was that the tadpoles from the first group would associate the smell of a newt with the idea of very great danger. The second group also had to learn to be afraid of newts, but not so much. Finally, the third group was not supposed to be afraid of newts at all.
The reaction of tadpoles to frightening stimuli, as already mentioned, is to slow down their movements. The authors measured the strength of this reaction as follows. A straight line was drawn on the bottom of each jar, dividing the jar in half. For four minutes before adding the scented water, the researchers counted how many times the tadpole crossed the line. If he did this less than six times in four minutes, he was excluded from the experiment. Then odors were added to the water and the number of crossings was counted again for four minutes. The ratio of the number of crossings before and after the addition of odors was used as a measure of fear.
As one would expect, during the training process, tadpoles from the first group were very afraid, those from the second group were weakly afraid, and the control group, which received only the smell of newt, was not afraid at all.
Three days later, all tadpoles changed the water and began the main stage of the experiment. Each of the three groups of tadpoles was divided into three more parts. The first part was given the smell of a newt, the second - the smell of a tiger salamander, which is a fairly close relative of the newt, the third - the smell of an African clawed frog, which belongs to another order of amphibians.
Of these three species of potential predators, wood frogs can only encounter the tiger salamander in nature.
Tadpoles from the control group, which had not developed a fear of newts, were not afraid of any of the three odors. Tadpoles that had developed a strong fear of newts were frightened by all three smells. What frightened them most was the smell of newt, which was used during “training”. The smell of the salamander, a close relative of the newt, frightened them a little less, the smell of the clawed frog - even less. Finally, the tadpoles, which had developed only a moderate fear of the newt, were frightened by the smells of the newt and the salamander, but remained indifferent to the smell of the clawed frog.
Thus, in tadpoles, as in fish, the degree of “generalization of the predator image” depends on the magnitude of the danger that is associated with a known predator. The greater the danger posed by a known predator, the broader the “generalizations” the prey makes. As they say, when you get burned by milk, you blow on water. A similar phenomenon was previously discovered in birds, although in that case it was not a question of recognition by prey of predators, but of differentiation between poisonous and non-poisonous prey by predators (see: Unusual camouflage in frogs is associated with the ability of predators to generalize, “Elements”, 03/13/2006 ).
The “ability to generalize” discovered in tadpoles does not mean that tadpoles have any particularly outstanding intelligence. Conditioned reflexes, that is, reactions to certain stimuli developed during life, are always “generalized” to one degree or another. In other words, if a reflex has been developed to a specific stimulus, then another, but very similar stimulus will most likely cause the same reaction. Moreover, the more different the stimulus is from the “learned” one, the weaker the reaction will be. This property of conditioned reflexes, which is determined by the basic principles of sensory perception and operation nervous system, in principle, is quite sufficient to explain both the phenomenon of “generalization of the image of a predator” itself and its dependence on the magnitude of the danger.
We continue to publish for you a review of episodes of the TV game “Who Wants to Be a Millionaire.” Today in the studio, father and daughter: Yuri Fedorovich Malikov and the talented, stunning, beautiful singer Inna Malikova. The Malikov family chose 200,000 as a fireproof amount. So here we go.
1. What do children leave when they play outside in winter? Option A: Snowball.
2. On what does the peasant renew his path in Pushkin’s poems? Option B: on firewood.
3. What did Cheburashka sing about himself: “I was once a strange toy...”? Option D: unnamed.
4. What is the common name for a driver's license? Option B: certificate.
5. What dance is the plot of the film “Winter Evening in Gagra” built around? Option C: Step.
6. On the territory of which states is the reserve located? Belovezhskaya Pushcha? Option C: Belarus and Poland.
7. What color are the most difficult ski slopes marked in Russia and Europe? Option D: black
8. What was the sail made of in the song “The Glorious Sea - Sacred Baikal”? Option: from a caftan. On this question The Malikov family did not know the answer. Therefore, they could not do without a hint; they took the “Right to Error”. They took “Overcoat” as their first option, but it turned out to be wrong. Then they took the second option “Kaftan”.
9. In what year was construction completed on the Sagrada Familia in Barcelona? Option D: It's not over yet. It was difficult for the Malikovs to answer this question and they decided to call family friend Anatoly. Anatoly said that he was recently in Barcelona and saw this cathedral; construction has not yet been completed.
10. What number of points in tennis is called the word “Love”? Option A: A. They wanted to call one more person, but the tip had already been used. They can no longer call anyone. Then it was decided to take the clue “help from the audience.” Viewers voted for option D - 40%. Inna decided to agree with the audience and choose option D, but the presenter stopped her and advised her to use another hint. Option D gone.
11. Which member of the Beatles received the middle name Winston at birth? Option A: John Lennon. Although Inna asked a question about music, she did not know the answer to this question. The players decided to go with John Lennon.
12. What happens to the tadpole of the American wonder frog as it grows into an adult animal? Option: shrinks in size. The Malikov family decided to take the money. Option: Inna decided to choose option D: changes gender. They found the question very interesting.
The guests' winnings amounted to 200,000 rubles. And now in the players’ chairs are the famous writer Semyon Altov and the super famous singer and guitarist Valery Syutkin.
1. What was the name of one of Dunno’s friends? Option D: Avoska.
2. Which horse is considered a symbol of poetic inspiration? Option A: Pegasus.
3. What do sailors do with mooring lines when leaving the pier? Option C: They give it away.
4. What is the name of the compiler of a perfume in France? Option C: “Nose.”
5. Where, according to Vladimir Mayakovsky, does the earth begin? Option D: From the Kremlin
6. Which Latin letter gave the English name to the clothing we call a T-shirt? Option D: T
7. How many times is a billion more than a thousand? Option D: a million times. To answer correctly, players had to remember math.
Hello, dear ladies and gentlemen. In this article we will discuss one of the interesting questions from today's game show "Who Wants to Be a Millionaire?"
Answers to all the game’s questions can be read in an article that will soon be published on the Sprint-Answer website. This will be an article with an overview of the game and all the questions and answers in it.
What happens to the American Wonderfrog tadpole as it grows into an adult?
The amazing frog, or Guiana water toad, is a tailless amphibian from the tree frog family that lives in South America. The name is given due to the size of the tadpoles (body length up to 25 cm), exceeding the size adult 3–4 times.
Earless tree frogs that prefer the northeast of the South American continent. Their body and head are slightly flattened. And spend free time they love in trees. And in Southern lives amazing frog from the tree frog family. It’s a paradox, but an adult reaches a size of only 5 centimeters, and the tadpoles grow up to 25. There is also a poisonous tree frog – the Brazilian tree frog, with blood-red spots on its back.
- becomes moldy
- decreases in size
- grows wings
- changes gender
The correct answer to the game show question is: shrinks in size.