He decided to create a real dinosaur (3 photos). Modern reptiles are descendants of dinosaurs Modern descendant of dinosaurs

IN Lately Increasingly, there are reports in the media that scientists can easily resurrect dinosaurs that went extinct 65 million years ago. However, in reality, everything is not as simple as it seems to those who are not familiar with all the intricacies of these studies. Because you can't actually resurrect dinosaurs. But you can create it again.

There are only two ways to “resurrect” an extinct animal. The first of them was practiced back in the twentieth century. Its essence is that if the wild ancestor of some domestic animals becomes extinct, then its appearance can be restored by selectively crossing representatives of the most primitive breeds descending from this ancestor. It was in this way that back in the 70s of the last century, German biologists managed to “resurrect” the extinct ancestor (more precisely, one of the ancestors) of modern horses - the tarpan ( Equus ferus ferus).

By crossing representatives of several breeds, in whose cells there were genes of tarpans (which were exterminated at the beginning of the twentieth century, that is, not so long ago), scientists managed to create a creature that appearance which absolutely exactly corresponded to that of the ancestral form. Subsequently, these tarpans were released into the wild, and now several herds of these animals graze in Germany and Poland. It is interesting that over several generations appearance did not undergo significant changes - which suggests that the “resurrection” was successful, and these animals apparently do contain most of the genes of the wild ancestor of the horse. However, it is impossible to verify this, since the genetic data bank of the tarpans themselves has not been preserved.

However, a similar approach is not applicable to dinosaurs - after all, there are no domestic breeds of these reptiles. True, there are descendants of this group, that is, birds, and a group of reptiles has been preserved, very close to the ancestral form of “terrible lizards” - crocodiles, but crossing representatives of these taxa, which are very distant from each other in evolutionary terms, will not yield anything (and it is purely technically impossible - the difference in genomes is too great).

Another method of “resurrection” is based on the creation of a hybrid embryo (read more about it in the article “What are the dangers of hybrid embryos?”). If the DNA of an extinct animal has been preserved in full, then it can be transplanted into the nucleus of the germ cell of a representative of the closest species, and thus the desired organism can be grown. With birds and reptiles it’s simple - all their development takes place in the egg, but a mammalian embryo at a certain stage needs to be transplanted into the body surrogate mother, in the role of which is a female of the same, closest species (for example, in the case of the “resurrection” of a mammoth, it will be an Asian elephant). In this way, biologists plan to “resurrect” the mammoth, woolly rhinoceros, big-horned deer and some others prehistoric giants, as well as exterminated in the twentieth century marsupial wolf(for more information about what it is, read the article “Wolves were afraid to go into the forest...”), the DNA of which is perfectly preserved and, as they say, is waiting in the wings.

However, this trick will not work with dinosaurs - scientists do not have a single DNA sample of these giants. The fact is that the last representatives of this group died out about 65 million years ago, and during this time all the bones of these giants managed, as they say, to recrystallize, that is, all the organic matter in them was replaced by inorganic substances, so in fact now they They are blocks of stone, somewhat similar to parts of the body of dinosaurs. Under such conditions, DNA cannot be preserved. Besides, in Mesozoic era there were no glaciations and permafrost, therefore, it is not possible to find the corpse of a “terrible lizard” that would lie frozen for millions of years (as often happened with mammoths).

So, as you can see, it is impossible to “resurrect” dinosaurs. However, scientists are convinced that they can be created anew. True, these will be completely different dinosaurs, outwardly having nothing in common with the real-life giants. But at the same time, they are quite complete.

This technique is based on the fact that genes early development(homeotic), which control the formation of the first stages of the embryo - the structures are quite conservative, and are often almost completely preserved in the descendants. This is why the human embryo is early stages looks like a fish, then an amphibian, and only then acquires features specific to mammals. Therefore, birds, of course, still have homeotic genes from dinosaurs. During the formation of the embryo, they even work, but very a short time- then special proteins “turn them off” so that the work of homeotic genes, specific only to birds, starts.

But what if we could somehow prevent these dinosaur gene shutdowns? Scientists from McGill University (USA), led by Hans Larsson, discovered that at the early stage of development of a chicken embryo, the embryo has a tail similar to a reptilian one. But then, at a certain point, the work of the genes responsible for its formation ends, and the tail disappears. Dr. Larsson and his colleagues tried several times to block the activity of proteins that turn off tail genes. In the end, they managed to do this, but the “tailed” chicken soon died, never really formed.

Ontogeneticists John Fallon and Matt Harris from the University of Wisconsin (USA) took a different path. They, experimenting with mutant chicken embryos, noticed that some of them had strange outgrowths on the jaws of the embryo. These “bumps”, upon closer examination, turned out to be saber-shaped teeth, which were identical to the teeth of embryonic alligators and, most interestingly, some small Jurassic dinosaurs.

It was later discovered that these mutants had a recessive gene that normally kills the fetus before birth. However, as a side effect of its activity, this gene includes another, which is the homeotic gene of dinosaurs, responsible for the formation of teeth. Interested in this phenomenon, Fallon and Harris created a virus that behaved like a recessive gene, but was not lethal to the embryo. When it was introduced into normal embryos, they began to grow teeth, and no harmful side effects it was not observed. However, the “nibbler” was not allowed to hatch - according to US law, hybrid embryos must be destroyed 14 days after the completion of the experiment.

However greatest success Dr. Arhat Abzhanov from Harvard University managed to achieve this. He calculated which of the homeotic genes of dinosaurs are responsible for the formation of a typical reptilian face instead bird's beak. He was also able to identify proteins that “turn off” these genes.

After this, Abzhanov added other proteins to the embryonic cells that blocked the activity of the “switches,” as a result of which the latter stopped working. As a result, there was no one to turn off the dinosaur genes, and the chicken grew a quite cute face, somewhat reminiscent of a crocodile. At the same time, the embryo itself did not die - it continued to actively develop. However, after 14 days, it was necessary, to Abzhanov’s great chagrin, to kill him too.

All these studies suggest that creating dinosaurs from birds is fundamentally possible. True, biologists still do not know all the homeotic genes left over from dinosaurs in birds, but establishing this is not so difficult - after all, there is a “control” group, that is, crocodiles. All the intricacies of their work have not been fully studied, however, this is just a matter of time. So it is possible that in the near future geneticists will still be able to turn a bird into a small feathered dinosaur from the genus Maniraptora, like those that existed in the mid-Jurassic period.

It should be noted right away that this creature, of course, will not be a representative of a species that already lived on our planet - after all, its genome will include avian DNA, which was absent in classical dinosaurs. This will be a representative of a new species, created by people, but with a structure and physiology characteristic of real dinosaurs.

The famous American paleontologist Jack Horner, who once participated in the film "Park Jurassic", intends to bring to life a movie script and create a real living dinosaur. According to the scientist, there is nothing particularly difficult in this, and you won’t even have to look for a prehistoric mosquito that fell into the resin after barely drinking dinosaur blood. Bring out ancient reptile will help completely modern creatures- those that, according to one theory, descended from dinosaurs. It's about about birds.

The famous American paleontologist Jack Horner, who once participated in the work on the film "Jurassic Park", intends to implement the movie script and create a real living dinosaur. Photo: wikipedia.org

“We will take a chicken embryo as a starting point and use genetic engineering to make it go back in time until we “pull out” the dinosaur that is hidden inside it. Initially, it will not be exactly a dinosaur, but a creature that has many of its features,” the scientist said in an interview with ABC. The subsequent "dinosaurization" of this creature will not take much time, according to Horner - about five, seven years.

We will take a chicken embryo as a starting point and use genetic engineering to make it go back in time until we “pull out” the dinosaur that lurks inside it. Photo: Global Look Press

It is worth noting that the idea of ​​​​creating a “kurosaurus” (or “dinokura” - whatever you like) in itself is not so new. The first loud statements in the press on this matter were made several years ago. For example, Horner’s colleague from Canada Hans Larsson announced work on a similar project back in 2009, while clarifying that it was the American paleontologist who inspired him to accomplish this.

But Horner himself does not sit still. “When I was little, I dreamed of two things. The first was to become a paleontologist. The second was to have my own dinosaur,” the scientist previously admitted. In fact, he became a paleontologist, and as he learned more and more about dinosaurs, he became increasingly fascinated by these prehistoric animals, and the desire to fulfill his second childhood dream grew. And if you believe Horner himself, there is nothing left before its implementation.

In the first stages, the chicken embryo develops the features of a dinosaur: teeth, paws with three fingers. Photo: Global Look Press

"Kurosaurus" with fangs is almost a reality

The process of creating a “kurosaurus” as presented by Horner does not look so complicated. But there are nuances: for example, it is impossible to grow a dinosaur from an ancient drop of blood, as in the same “Jurassic Park”. “If you take a piece of amber with a mosquito inside it, and extract something from the mosquito, and then clone it, and so many times, you will get a whole room of mosquitoes. And also a whole bunch of trees,” Horner joked at the conference scientific foundation TED last year. “So if you want dinosaur DNA, you need to look for a dinosaur.”

According to the researcher, it can be found in the descendants of dinosaurs - birds. And chicken was chosen among them as the most studied species. “We know its genome by heart,” Inopressa quotes Horner. “This will not be just a genetic modification. We intend to awaken atavistic genes in the DNA of birds and make them appear again,” explained the paleontologist. “First, we need to identify specific genes in the chicken genome and change the level of certain regulatory proteins. In the first stages of the chicken embryo "The features of a dinosaur are developing: teeth, paws with three fingers."

By the way, the gene responsible for the presence or absence of teeth has already been found, so this moment Scientists could theoretically create a chicken with tusks. But not a monster - but a creature of quite ordinary chicken size. But even in a few years, when scientists get to a real dinosaur, the result of their work will not be dangerous. As the scientist stated in an interview with Live Science, he wants to breed a small herbivorous dinosaur. “I’ll make sure that my new pet doesn’t eat either my other pets or myself.”

We think we own heaven. But a group of creatures capable of flight remains the envy of air force created by man. These birds are descendants of dinosaurs. They inhabit all ecosystems globe, including the interior of Antarctica.

Origin of birds for a long time remained the subject of lively debate. Over the foreseeable period of time, several scientific versions of the origin and family ties birds and the emergence of flight in them, and for more than a hundred years they were purely hypothetical.

1. Heron fishing. (Photo by Attila Kovacs):

The hypothesis about the origin of birds from dinosaurs was first put forward in 1868 by Thomas Huxley. It was based on a comparison of the structure of Archeopteryx, an animal that lived about 150 million years ago in the Upper Jurassic. It had the characteristics of a typical reptile - special structure pelvis and ribs, teeth, clawed paws and a long, lizard-like tail. At the same time, the fossils had well-preserved imprints of flight wings, similar to those of modern birds.

2. A flock of white geese. (Photo by Jim Scalzo):

There are many similarities between birds and dinosaurs. common features in the structure of the skeleton. Among the possible closest relatives of birds, avimim is also considered - small predatory dinosaur from the Cretaceous period.

3. A pelican feeds its babies. (Photo by Monika Skkolimowska):

The first attempt to systematize animals was made in the 4th century BC. e. Greek scientist Aristotle - in his works “On the Parts of Animals” and “On the Origin of Animals” he identified all the birds known to him into the “highest genus” Ornithes. Despite the obvious imperfection of this system, until the second half of the 17th century, no new attempts were made to classify the animal world. Only to end of the 19th century century, new research has laid the foundation for modern ideas about the bird class system.

4. Heron. (Photo by Biju Boro):

Birds are everywhere, even in Antarctica. For example, the snow petrel nests in the interior of this continent at a distance of up to 440 km from the coast. Along the edges of the Antarctic shield, penguins (emperor, Adelie), giant petrel, and south polar skua nest in places.

5. Sandhill cranes. (Photo by Sam Greenwood):

Birds also inhabit the most waterless deserts and mountains, right up to the border of eternal snow. During migration, flocks of geese and cranes were sometimes observed flying at an altitude of 7000-9000 m. In 1973, an African vulture collided with a civil aircraft over Côte d'Ivoire at an altitude of 11,277 meters.

6. gray heron fishing. (Photo by Attila Kovacs):

Several families of birds have adapted to life at sea. Some species of penguins dive to depths of up to 300 m, and according to other information, emperor penguin can reach a depth of 535 meters.

7. Tricolored heron. Chick. (Photo by Rhona Wise):

It is the ability to fly that determines the characteristics of this class of animals, although there are a relatively small number (about 60 species) that are flightless or almost flightless birds, in the course of evolution, one way or another, they lost the ability to fly that their ancestors had.

8. Pelicans. (Photo by Amir Cohen):

Flight requires a very large expenditure of muscle energy, so the level of metabolism in birds is extremely high and the need for food is great: its daily norm is 12-28% total mass bodies. If we project these data onto a person, then a 70-kilogram character would have to eat up to 20 kg of food per day if he were a bird.

9. The duckling is hiding from the rain. (Photo by David L. Ryan):

All bird species are characterized by the presence of feathers that are not found in other modern animals. Feathers cover the entire body of the bird, with the exception of the beak and the distal parts of the hind limbs. It is believed that feathers originated as a result of evolutionary transformations of reptile scales.

10. Gray Heron. (Photo by Attila Kovacs):

How many feathers does a bird have? Total number feathers large species more than small ones. For example, hummingbirds have about 1,000 feathers, seagulls have up to 6,000, and swans have 25,000.

11. Robins are waiting for their parents in the nest. (Photo by Frank Rumpenhorst):

The pen is an almost perfect mechanism. It provides the ability to fly, forming load-bearing planes(wings, tail), and creates a streamlined body. Feathers protect the skin from mechanical damage. The waterproof and heat-protective functions of the plumage are very effective.

12. Stilt walkers. (Photo by Sam Yeh):

Like any sophisticated mechanism, feathers require careful maintenance, and birds spend about 9% of their time daily cleaning their plumage, bathing and dust bathing.

13. Stork. (Photo by Rhona Wise):

Descendants of dinosaurs do not smell. They do not have sweat glands. Cooling of the body is achieved using highly developed respiratory system. Birds also cool down by being in the shade or in water.

14. Herons. (Photo by Attila Kovacs):

No teeth. It is interesting that modern birds lack teeth - they are partly replaced by the sharp edges of the beak, with which birds capture, hold and sometimes crush food. Due to the loss of teeth, the task of grinding food is transferred to the stomach.

15. Canada geese. Struggle. (Photo by David L. Ryan):

The respiratory system of birds is also characterized by signs of adaptation to flight. This organ system in birds is considered one of the most complex among all groups of animals. The more intense the flapping flight, the more intense the breathing process.

16. Godwits. (Photo by Chris Purnell):

The heart rate of birds is also high, and in flight, compared to rest, the heart rate increases noticeably. So, a sparrow’s resting pulse is about 460 beats/min, and in flight it’s about 1000 beats/min!

17. Heron's nest. (Photo by Anupam Nath):

Birds are not stupid animals. A well-developed brain allows birds to develop complex behaviors and adapt to a wide variety of situations. The most striking demonstration mental abilities birds are considered to be the training of songbirds to sing, the repetition of human speech by parrots, methods of obtaining food in a number of species and the ability of corvids to solve complex problems offered to them in special experiments.

18. 3 little swans. (Photo by Matt Campbell):

Eyes are the most powerful avian apparatus. Many birds have good distance vision (the peregrine falcon is able to see a small bird at a distance of more than 1 km). In some species the field of view reaches almost 360°. Vision in birds is noticeably more acute than in other groups of vertebrates - this is explained significantly big amount light-sensitive cells in the retina.

19. Dove. (Photo by Dominique Faget):

Sound signals are extremely important in the life of birds. They ensure the protection of feeding and nesting territories from the invasion of strangers, attracting females for breeding, and warning relatives and chicks about impending danger. There are dozens of sound signals in the language of birds (distress, warning, food, courtship, mating, aggressive, flocking, nesting, and so on).

Some birds, for example, lyrebirds, have a phenomenal ability to imitate all kinds of sounds, ranging from the voices of birds, animals, humans, and ending with various man-made sounds, including playing the flute and even the sounds of car alarms and chainsaws.

20. Goose family. (Photo by Tom Dorsey):

Flight! The flight of birds is usually divided into two main types: active (flapping) and passive (soaring). Birds usually use more than one type of flight, but combine them. The flapping of the wings is followed by phases when the wing does not move: this is gliding flight, or soaring. This flight is typical mainly for birds of medium and large sizes, with sufficient body weight. Hovering in place relative to the surrounding air is a challenging task for birds. In fact, hummingbirds are the only group of birds adapted to do this.

Birds move along branches, ground and water using their hind legs. And also, any bird does not drown in water and swims when necessary.

21. Gray heron catches fish. (Photo by Attila Kovacs):

The migration routes of some birds consist of many segments, between which the birds rest and look for food. The reasons for bird migration are seasonal changes environment. The Arctic tern is considered the absolute champion in terms of migration distance, migrating seasonally from the Arctic to the Antarctic, covering a distance of up to 70-90 thousand km per year! Also, one of the longest migrations in the world, lasting up to 26 thousand km, is performed by the round-nosed phalarope.

Watching birds fly prompted people to invent the first aircraft, and its further study continues to influence the development of modern aviation.

22. White stork nest on a cell tower. (Photo by Paul Hanna):

Regarding organic material, can dinosaur DNA be extracted from it? Not really. Paleontologists constantly argue about the suitability of organic matter, but DNA has never been extracted (and, apparently, never will be able to).

Take, for example, the Tyrannosaurus rex (which is a rex). In 2005, scientists used weak acid to extract weak and pliable tissue from the remains, including bone cells, red blood cells and blood vessels. However, subsequent studies showed that the find was just an accident. got seriously excited. Additional analysis using radiocarbon dating and scanning electron microscopy showed that the material under study was not dinosaur tissue, but bacterial biofilms - colonies of bacteria linked together by polysaccharides, proteins and DNA. These two things look quite similar, but have more in common with dental plaque than with dinosaur cells.

In any case, these findings were very interesting. Perhaps the most interesting thing we haven't found yet. The scientists perfected their techniques and, when they got to the lufengosaurus nest, they braced themselves. Captivating? Absolutely. Organic? Yes. DNA? No.

But what if it's possible?

there is hope

Over the past ten years, advances in stem cells, ancient DNA resuscitation, and genome restoration have brought the concept of “reverse extinction” closer to reality. However, how close and what this might mean for the most ancient animals is still unclear.

Using frozen cells, scientists successfully cloned a Pyrenean ibex known as a bucardo in 2003, but it died within minutes. For years, Australian researchers have been trying to bring it back to life. southern view frogs that gave birth with their mouths, the last of which died several decades ago, but their venture has still not been successful.

This is how, stumbling and cursing at every step, scientists give us hope for more ambitious resuscitations: mammoths, passenger pigeons and Yukon horses, which became extinct 70 thousand years ago. This age may confuse you at first, but just imagine: this is one tenth of a percent of the time when he died the last dinosaur.

Even if dinosaur DNA were as old as yesterday's yogurt, numerous ethical and practical considerations would leave only the craziest of scientists among those who would support the idea of ​​resurrecting dinosaurs. How are we going to regulate these processes? Who will do this? How will resurrecting dinosaurs affect the Endangered Species Act? What will failed attempts bring, besides pain and suffering? Suddenly we reanimate fatal diseases? What if invasive species will they grow on steroids?

Of course, there is growth potential. Like the representation of wolves in Yellowstone Park, a “rollback” of recently extinct species could restore balance to disturbed ecosystems. Some believe that humanity owes a debt to the animals it has destroyed.

The DNA problem, for now, is a purely academic issue. It is clear that resurrecting some frozen baby mammoth from a frozen cage may not arouse much suspicion, but what to do with dinosaurs? The discovery of a Lufengosaurus nest may be the closest we've ever gotten to Jurassic Park.

As an alternative, you can try to crossbreed an extinct animal with a living one. In 1945, some German breeders claimed to have been able to revive the aurochs, the long-extinct ancestor of the modern cattle, but scientists still do not believe in this event.

Scientists have found in Tanzania the remains of a likely ancestor of dinosaurs that was more similar to a crocodile than to the first “real” dinosaurs, Eoraptors and other “terror lizards,” according to a paper published in the journal Nature.

This is how the artist imagined the ancestor of all dinosaurs, Teleocrater rhadinus, eating the remains of a lizard. Natural History Museum, London/Mark Witton

"This discovery shows that the first dinosaurs had a lot in common with the first crocodiles, and that the 'bird' anatomy did not appear in them immediately, as we previously thought. Paleontologists don't like the word 'lost link of evolution,' but in this case it is acceptable - Teleocrater connects dinosaurs and their common ancestor with crocodiles,” said Ken Angelchuk from the Field Museum of Natural History in Chicago (USA).

The Chicken, the Dinosaur and the Egg Problem

The first dinosaurs, as paleontologists now believe, appeared at the end Triassic period- about 240 million years ago, after the disappearance of all the large animal lizards that dominated the Earth in the Permian period. The main competitors of dinosaurs for the “crown” of the most successful animals on Earth were crocodiles, which at that time reached gigantic sizes and lived not only in reservoirs, but also on land.

Both crocodiles and dinosaurs are close relatives, whose ancestors are believed to have split in the mid-Triassic period. How and when this happened, paleontologists do not yet know, since fossils from this time are quite rare.

On the other hand, most scientists believed that they “diverged” quite quickly, since ancient dinosaurs did not look like crocodiles - they had long flexible necks, were able to walk on two legs and their limbs were adapted for fast running.

Drawing: Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"/Gabriel Lio

Angelchuk and his colleagues discovered that the earliest ancestors of dinosaurs were in fact more similar to crocodiles than to their closest descendants by studying mid-Triassic rocks that formed in southern Tanzania around the Ruhuhu River.

Here, paleontologists discovered the remains of a three-meter creature that did not resemble either the Eoraptors (the first dinosaurs that lived in Argentina 230 million years ago), or the Nyasasaurs found by the authors of the article in Tanzania in 2012, or other dinosaurs and their ancient relatives. In general, we can say that it was not similar to any ancient reptile or their modern descendants.

Dinosauropticecrocodile

This animal, as Angelchuk says, was more like a monitor lizard or a “thin” crocodile with unusually long legs and neck than a dinosaur - it moved on four legs and had primitive joints that did not allow it to run fast, and also had a number of other features ancient and modern reptiles.

However, the creature was a dinosaur, as general device its anatomy was closer to that of a "terror lizard". For example, their neck ribs were longer than other bones of a similar type, and they also had a unique shape, not typical for crocodiles. In addition, this mysterious creature had the jaws of a dinosaur and front paws unusual for crocodiles.

Scientists have named this bizarre creature Teleocrater rhadinus, which means “a thin animal with a closed pelvis,” indicating the inability of these creatures to run as fast as dinosaurs.

As is often the case in paleontology, Teleocrater rhadinus was actually discovered much earlier, in the mid-1950s, when British paleontologist Alan Charig was studying fossils his team had found in Tanzania in the 1930s. He did not attach any importance to these bizarre remains and did not see in them the ancestor of all dinosaurs, since the remains he found were incomplete.

Angelchuk and his colleagues corrected Charig's mistake by naming their discovery by the name that their British predecessor had come up with for it. According to scientists, the discovery of Teleocrater rhadinus completely changes the history of the evolution of birds, dinosaurs and crocodiles and closes the most important gap in the history of their origin, which scientists have been arguing about for several decades.