In the Mesozoic era, which lasted for about 175 million years (45 - Triassic, 60 - Jurassic, 70 - Cretaceous periods), "terrible lizards" - dinosaurs, ichthyosaurs and flying dinosaurs - reached their apogee. In total, there were, according to current data, 25 families and 218 genera. Among the dinosaurs there were small ones - the size of a chicken or a cat, and gigantic ones - up to 30-40 meters and 50 tons of weight; predators and herbivores. At the end of the Mesozoic, most of them became extinct. Only a tiny fraction of the reptiles of that era remained on Earth: lizards, snakes, crocodiles and turtles. And it seemed that these representatives of the mighty reigning dynasties would live and rule forever.
Between the disappearance of dinosaurs and the appearance of humans lies a gap of 90 million years - at least until recently official science has argued. But in recent years, in different countries, no, no, and there is evidence that dinosaurs existed in the relatively "recent" past - or rather, simultaneously with humans, and people saw them. And this conclusion is not made by scientists on the basis of "verbal portraits of dragons", which can be found in many legends about valiant knights and tales of mighty heroes.
And the evidence has already been found. The renowned archaeologist Karl Bauch has discovered amazing footprints in the Palaxi Valley in Texas. The footprints of a dinosaur are clearly visible on the limestone slab, and half a meter away from them are the traces of bare human feet. A dozen prints where the left and right feet alternate at the correct distance! These traces were considered fake until physiologist Dale Peterson undertook to verify their authenticity. “There is no doubt that we are dealing with human footprints,” he said. - The nature of the distribution of body weight leaves no room for other hypotheses: only a person walks like this! These footprints, according to experts, appeared in limestone in the same era as the dinosaur footprints.
The Palaxi River tracks are not the only example. Back in 1931, the American geologist G. Burru reported on the findings of human footprints in layers that were … 250 million years old! He found ten such tracks a few miles northwest of Mount Vernon. But then there were no mammals, not even dinosaurs!
And these are not isolated examples. We can say that the North American Indians drew "terrible lizards" almost from life. Moreover, some reptiles even managed to be tamed: the Mexican sculpture "Woman playing with an unknown animal" speaks about it. The lamellar crest on the back, tail and massive hind legs resemble a small dinosaur - or, to be more precise, the "unknown animal" is very similar to a somewhat crude and exaggerated depiction of a stegosaurus - a dwarf, however, because even a baby stegosaurus that lived on earth in time of the Jurassic period, was much larger than a person. And an adult "specimen" of this herbivorous reptile weighed at least two tons.
How could this have happened and where is the error? So, there is reason to doubt, if not the fact of the death of dinosaurs, then at least the time when it happened? But Isaac Newton in 1728 published the book “The Chronology of Ancient Kingdoms Amended”, in which he expressed serious doubts about the correctness of the generally accepted chronology of historical facts. His assumptions are also confirmed by specialists in different fields of knowledge (physics, mathematics, biologists). In their opinion, the history of mankind, and of the entire planet, is much shorter than we are used to thinking. And the fault lies with the "most reliable" radiocarbon method discovered by Nobel laureate W. Libby. It consists in the fact that when pieces of bones, tissue, wood or organic remains are burned, then their age is determined by the content of radioactive carbon in the gases. So, this method sometimes gives very large errors. And in order to determine the true age, it is necessary to calculate complex corrections reflecting changes in the composition of the atmosphere over millennia, which is almost impossible to do. But the erroneousness of Libby's method has already been proven: for example, the famous archaeologist Vladimir Miloichich conducted a series of experiments, and it turned out that the shell of a currently living American mollusk with a radioactivity of 13.8 is about 1200 years old; blooming wild rose from North Africa (radioactivity 14.7) is already 360 years old; and the Australian eucalyptus (radioactivity 16.31), according to Libby's method, will exist only after 600 years!reflecting changes in the composition of the atmosphere over millennia, which is almost impossible to do. But the erroneousness of Libby's method has already been proven: for example, the famous archaeologist Vladimir Miloichich conducted a series of experiments, and it turned out that the shell of a currently living American mollusk with a radioactivity of 13.8 is about 1200 years old; blooming wild rose from North Africa (radioactivity 14.7) is already 360 years old; and the Australian eucalyptus (radioactivity 16.31), according to the Libby method, will exist only after 600 years!reflecting changes in the composition of the atmosphere over millennia, which is almost impossible to do. But the erroneousness of Libby's method has already been proven: for example, the famous archaeologist Vladimir Miloichich conducted a series of experiments, and it turned out that the shell of a currently living American mollusk with a radioactivity of 13.8 is about 1200 years old; blooming wild rose from North Africa (radioactivity 14.7) is already 360 years old; and the Australian eucalyptus (radioactivity 16.31), according to the Libby method, will exist only after 600 years!blooming wild rose from North Africa (radioactivity 14.7) is already 360 years old; and the Australian eucalyptus (radioactivity 16.31), according to the Libby method, will exist only after 600 years!blooming wild rose from North Africa (radioactivity 14.7) is already 360 years old; and the Australian eucalyptus (radioactivity 16.31), according to the Libby method, will exist only after 600 years!
So, perhaps, our Earth is not so old, and dinosaurs disappeared from the face of the planet not so long ago. But they still disappeared (with some exceptions, for example, the Loch Ness Monster or the dragon from Komodo Island). And yet the reason for this is not natural selection, as Charles Darwin believed.
The extinction of dinosaurs is one of the most mysterious pages in the history of life on our planet. For many millions of years, dinosaurs were the true masters of land, occupying the upper floors of the ecological pyramid. Among them were the largest animals that existed on earth: titanosaurs, brachiosaurs, diplodocus; the largest predators: tyrannosaurs, tarbosaurs, gigantosaurs. From the Triassic to the Late Cretaceous, dinosaur diversity increased. It seemed that nothing foreshadowed their disappearance without a trace. But at the end of the Cretaceous period, the entire thriving group of the planet's masters died out. There are many hypotheses regarding the causes of this phenomenon. In general, they can be divided into two groups: hypotheses explaining extinction by external, including extraterrestrial, causes, and hypotheses linking extinction with internal, biological factors.
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Of the hypotheses of the first group in recent years, the most popular and justified is the so-called "impact hypothesis", according to which at the end of the Cretaceous period (65 million years ago) the largest restructuring of the entire terrestrial and marine biota took place (Biota is a historically formed set of plants and animals, united general area of distribution), the direct cause of which was the fall of a large meteorite or asteroid to Earth near the Yucatan Peninsula in Mexico. According to scientists, this happened 65.51 million years ago and doomed dinosaurs and about 70% of other species of fauna to destruction. Some scientists believe that the giants died almost simultaneously. (Of course, the "Great Extinction" of the dinosaurs did not happen overnight, but nevertheless, by geological standards, almost instantly.) For example,the so-called "death fields" of dinosaurs are known in Central Asia, where in some areas along the foothills of the Tien Shan colossal accumulations of these dinosaurs stretch - the remains of millions and millions of individuals. The writer I. A. Efremov, who led the excavations in Mongolia, noted an interesting moment: often in burials, skeletons of old animals and young animals are found simultaneously. This could only happen as a result of some sudden catastrophe. Moreover, it was instant, like a lightning strike. In addition, the explosion threw enough ash, soot and ash into the atmosphere to practically stop the process of photosynthesis around the world. The sharp decline in green plants, which were the initial link in the food pyramid, led to the fact that further, as a chain, the extinction of various groups of marine and terrestrial organisms occurred. Dinosaurs were no exception. But the asteroid hypothesis does not allow explaining why some groups became extinct, while others still survived. Therefore, not all specialists - paleontologists and geologists - share this point of view. So scientists at the University of Pennsylvania believe that the fall of an asteroid in that era could even be a salvation for life on the planet, and the snag in the riddle of the extinction of lizards is that their disappearance was not caused by climate change, but was the result of other factors. They say that the fall of the asteroid only reduced the number of populations in the world by 80-90%, but could not destroy all polls, which would mean that the survivors could multiply again: But this did not happen. Studies of fossil remains of animals and plants have shownthat the mass extinction began 1 million years before the fall of the asteroid and this was associated with a change in the poles of the Earth. Apparently, this change took an unusually long time and had a very strong impact on the existence of flora and fauna, since in the moments between the pole changes the Earth was left without a magnetic field and was deprived of protection against the attack of the solar wind and radiation fluxes. And that in this case, only thanks to the fall of the asteroid, life on Earth was preserved and developed, since the dust ejected into the atmosphere became a barrier to the destructive solar radiation. Dinosaurs were well adapted to global warming and cooling. Apparently, most of them were even warm-blooded. But the effects of the shockwave from the asteroid impact killed off all large forms of reptiles. Only a few species survived, that is, only those reptiles survivedwho could go without food for a long time - crocodiles, snakes and lizards, or who could hide and get their food in the seas - turtles.
In general, most experts agree that on the border of the Cretaceous and Paleogene, earthly life experienced a profound crisis, which was caused by purely earthly reasons associated with the laws of development of life and the biosphere of the Earth as a whole. He was not the first, was not the strongest and most catastrophic; similar crises have happened in the history of the planet before. Life on Earth is not just a collection of simultaneously living animals and plants, but a complex self-regulating system. Its state, stable or unstable, depends not only and, possibly, not so much on external factors and influences, but on self-development and interaction of individual elements of this system: groups of organisms, animals and plants, changing their relations with each other and with habitat, etc. Special studies have shownthat in the case of the Late Cretaceous crisis, the extinction of both dinosaurs and other organisms was not simultaneous and sudden, but occurred over tens of millions of years. The crisis event 65 million years ago put only the last point in this process.
As for the dinosaurs themselves, we can list several purely biological and biospheric moments that indicate an internal imbalance in the structure and anatomy of the animals themselves and their relationship to the environment. Perhaps the tragic role in this was played by the "two-brains" of the giant herbivorous dinosaurs, and perhaps the largest reorganization of the planet's vegetation in the history of the Earth: angiosperms (flowering) plants, grass appeared, and cereals were becoming more common. For herbivorous animals feeding on more primitive plants, the transition to another "diet" required a significant restructuring of the entire enzymatic digestive system. Perhaps they were unable to overcome this purely physiological conflict.
Many other explanations have been proposed for the extinction of the dinosaurs. One of the first hypotheses related to space was the assumption made by the Soviet astronomer I. S. Shklovsky that the extinction was associated with a supernova outburst in our Galaxy. Its remnants are now the Crab Nebula. According to astronomers' calculations, harsh cosmic radiation from a supernova reached Earth around the time the dinosaurs became extinct. It probably became the fatal factor.
But all these theories can be challenged. Thus, researchers at the US National Academy of Sciences, although they agree that the death of dinosaurs and other life forms was the result of a series of catastrophes that changed the climate on Earth, but put forward an alternative theory. Analysis of rocks taken in the central part of the crater formed as a result of this collision on the Yucatan Peninsula proves that it happened 300 thousand years before the extinction of the dinosaurs. Professor Gertha Keller of Princeton University says that she finally managed to refute the idea that a single asteroid killed the dinosaurs. She claimsthat it was just one of the "major episodes" in a whole series of collisions of asteroids with the Earth (already found signs of three collisions with meteorites at that time) and giant volcanic eruptions together with global warming of the planet. The highlight of Keller's new theory is the shift in emphasis to unprecedented volcanic activity. Moreover, the results of the activity of "supervolcanoes" and "supermeteorites" are similar. We are talking about the so-called pillars of the mantle - global volcanic eruptions in the depths of the earth's mantle. A similar eruption under the Indian Ocean several million years before the extinction of the dinosaurs could have a most destructive effect on the entire earth's ecology. Hot magma, breaking through the crustal layer, formed a monstrous "mushroom" of lava more than a million cubic kilometers, with a diameter of about 1000 km. In our time, the remnants of that disaster, perhaps, are seven "hot spots": Iceland, Hawaii, Easter Islands, Reunion, Tristan, Louisville, as well as the Ethiopian region. And it was precisely as a result of those events that ancient monsters were erased from the face of the planet and a place was made available for mammals.
And more recently, in 2004, American and British scientists expressed a new paradoxical hypothesis about the causes of the death of dinosaurs. The fall of a giant meteorite and the onset of global cooling are not questioned. David Miller from the University of Leeds in England drew attention to the fact that in some modern reptiles, such as crocodiles, turtles, as well as in some fish, the sex of the offspring hatched from eggs depends on the ambient temperature. When the temperature deviates from the ideal, more males are born. New in theory is that as a result of the temperature imbalance in large reptiles, most of the males began to be born, which accelerated the degradation of the species.
However, the director of the Paleontological Institute of the Russian Academy of Sciences, Alexei Rozanov, believes that the reasons for the disappearance of dinosaurs are completely different. By the end of the Cretaceous, he argues, dinosaurs were so weak that they were on the verge of extinction for natural phylogenetic reasons. They have degraded. Their strength became their weakness. For the first time in nature, there were superpredators that had no competitors. The dinosaurs that reigned on Earth in the Mesozoic era had a perfect locomotor apparatus, they suppressed other species, far exceeded everyone in size. But they could not hunt small mammals, opossums and mice. As a result, the dinosaurs turned out to be closed on themselves - such systems in the biocenosis are considered weak, unstable. With their dictatorship, dinosaurs dug their own grave simply because they did not know how to adapt. To explainwhy the dinosaurs left the planet in a "formation" does not have to involve the hypothesis of a cosmic catastrophe: the former ruler could have been ruined by a chain of small events, such as droughts and floods, which for other species passed unnoticed.
Other scientists are highlighting biotic factors such as the extermination of dinosaur eggs by mammals, competition from mammals, excessive destruction of vegetation by dinosaurs, and diseases (unknown viruses and cancer). “The most mysterious event in the history of the Earth is the transition from the Mesozoic, the age of reptiles, to the Cenozoic, the age of mammals,” writes D. Simpson, one of the leading figures of paleontology. - The impression is as if during a performance in which all the main roles were played by reptiles, the curtain fell for a moment and immediately rose again, revealing the same scenery, but completely new actors: not a single dinosaur, other reptiles in the background as extras, and in the main roles - mammals, which were not even mentioned in the previous actions. Maybe,that the newly appeared placental mammals were more competitive than dinosaurs in the new climate and vegetation.
There is also a theory that can be classified as absurd from the point of view of "Homo sapiens". It, like others, is not confirmed by anything and consists in the fact that dinosaurs could well have reached such a high level of development that they left our planet or destroyed themselves during wars. Of course, you can laugh, but after all, dinosaurs had several times more time for evolution and development than we, intelligent ones.
But the most interesting thing is that, as scientists have discovered, the death of dinosaurs is not the only bio-disaster in the history of the Earth! The first mass extinction of an entire group of organisms occurred 370 million years ago. Then the psilophytes that reigned on land perished, and the giant racoscorpions in the ocean. After 130 million years, the catastrophe repeats itself: the turn of trilobites, ancient echinoderms, corals, sea lilies comes. Groups of ancient amphibians and some reptiles have sharply decreased, many ferns and a number of other plants have disappeared. And finally, relatively recently - only 2-3 million years ago - a number of giant mammals, like saber-toothed tigers, which had no natural enemies in nature, completely disappeared. In fact, they repeated the fate of the dinosaurs. And again the inevitable question arises: why in such cases some organisms die,and others begin to develop rapidly? After all, dinosaurs were much more adapted to various ecological cataclysms than miserable mammals at that time!
Meanwhile, all biological catastrophes have one common characteristic feature: those species of living beings die out, which in their organization are lower on the steps of the biological evolutionary ladder, giving way to more highly organized ones. With the disappearance of dinosaurs, mammals did more than just find living space. There was a powerful outbreak of the evolutionary development of this class of animals. The original answer to this question is given by the researcher A. V. Pronin: “No ecological and similar factors are the cause of the death of ancient organisms, since the“history of the world of organisms”shows that mass extinctions were not related to ecological groups, but to systematic ones (for example, all dinosaurs - sea, land, flying). Systematically, selectively and purposefully, only Reason can act, which destroyed some groups,as those he disliked, and he kept others alive, more beautiful and perfect. These species were simply destroyed by people, Higher People - by Gods, since their form and structure did not correspond to the laws of Beauty and Harmony. These species did not satisfy Them with their imperfection, and therefore They mercilessly destroyed these species … Yes, yes! Dinosaurs did not become extinct … They were destroyed as a dead-end branch, as failed forms of creativity, as purely experimental samples … For no catastrophe leads to a definitively selective nature of "extinction". No catastrophe destroys the strong, more protected, but low-organized, from whom there is nothing to expect in the future, in order to give living space and freedom to the less protected, still weak and small, but more highly organized … "more beautiful and perfect. These species were simply destroyed by people, Higher People - by Gods, since their form and structure did not correspond to the laws of Beauty and Harmony. These species did not satisfy Them with their imperfection, and therefore They mercilessly destroyed these species … Yes, yes! Dinosaurs did not become extinct … They were destroyed as a dead-end branch, as failed forms of creativity, as purely experimental models … For no catastrophe leads to a definitively selective nature of "extinction". No catastrophe destroys the strong, more protected, but low-organized, from whom there is nothing to expect in the future, in order to give living space and freedom to the less protected, still weak and small, but more highly organized … "more beautiful and perfect. These species were simply destroyed by people, Higher People - by Gods, since their form and structure did not correspond to the laws of Beauty and Harmony. These species did not satisfy Them with their imperfection, and therefore They mercilessly destroyed these species … Yes, yes! Dinosaurs did not become extinct … They were destroyed as a dead-end branch, as failed forms of creativity, as purely experimental samples … For no catastrophe leads to a definitively selective nature of "extinction". No catastrophe destroys the strong, more protected, but low-organized, from whom there is nothing to expect in the future, in order to give living space and freedom to the less protected, still weak and small, but more highly organized … "as their form and structure did not correspond to the laws of Beauty and Harmony. These species did not satisfy Them with their imperfection, and therefore They mercilessly destroyed these species … Yes, yes! Dinosaurs did not become extinct … They were destroyed as a dead-end branch, as failed forms of creativity, as purely experimental samples … For no catastrophe leads to a definitively selective nature of "extinction". No catastrophe destroys the strong, more protected, but low-organized, from whom there is nothing to expect in the future, in order to give living space and freedom to the less protected, still weak and small, but more highly organized … "as their form and structure did not correspond to the laws of Beauty and Harmony. These species did not satisfy Them with their imperfection, and therefore They mercilessly destroyed these species … Yes, yes! Dinosaurs did not become extinct … They were destroyed as a dead-end branch, as failed forms of creativity, as purely experimental models … For no catastrophe leads to a definitively selective nature of "extinction". No catastrophe destroys the strong, more protected, but low-organized, from whom there is nothing to expect in the future, in order to give living space and freedom to the less protected, still weak and small, but more highly organized … "as purely experimental samples … For no catastrophe leads to a definitively selective nature of "extinction". No catastrophe destroys the strong, more protected, but low-organized, from whom there is nothing to expect in the future, in order to give living space and freedom to the less protected, still weak and small, but more highly organized … "as purely experimental samples … For no catastrophe leads to a definitively selective nature of "extinction". No catastrophe destroys the strong, more protected, but low-organized, from whom there is nothing to expect in the future, in order to give living space and freedom to the less protected, still weak and small, but more highly organized …"
So, we came to where we started, although, at first glance, it is rather absurd: maybe humanity existed on Earth in those distant centuries and it was his activity that "contributed" to the disappearance of entire species, because even now the Red Book already groans from hundreds and thousands of names of "untimely departed" representatives of flora and fauna.
The question of what killed the dinosaurs has been especially actively discussed in the last 10 years - and it seems that the debate will not end soon …
V. Syadro, T. Iovleva, O. Ochkurova
