Scientists have resurrected an extinct goat by cloning. Baiji river dolphin

Over the history of mankind, the biological diversity of the planet has undergone several dramatic changes. Some species of animals have disappeared from the surface of the Earth. The main factor global change - vigorous activity person.

In the sad annals of the animal world there is a fresh chapter in which now extinct animals could be seen in wild nature or zoos a few years ago. Animal species that have gone down in history literally before our eyes - in the editorial material.

Mariana Mallard (1981)

Mariana mallard lived on only three islands Pacific Ocean. The species began to disappear in the middle of the last century. The cause of the extinction of the Mariana mallard was the work to drain the swamps for agriculture after the Second World War.

The last member of the species died in captivity in 1981.

Canarian black oystercatcher (1994)

Next on the list of extinct animals is the Canarian black oystercatcher. This bird species was widely distributed along the coast. West Africa.

The Canary black oystercatcher was killed by the extermination of their main food - mollusks. Excessive commercial fishing off the coast of West Africa has resulted in birds starving to death.

The last representative of the species was seen in the late 80s. The species was officially recognized as extinct in 1994. Only four stuffed Canary black oystercatchers have survived in the world.

Java Tiger (1994)

The tiger subspecies that inhabited the Indonesian island of Java was also declared extinct in 1994. The reason for the extinction of the Javan tiger was human agricultural activities. With the reduction of the habitat, the remaining individuals moved to the mountains.

The catastrophic situation around the population of the Javan tiger turned out to be in 1950, when only 25 representatives of the species were found on the island.

Ibex Ibex (2000)

During the Middle Ages, the most common animal species in the Iberian Peninsula was the bucardo, or Iberian ibex. Problems began in the 19th century, but the situation became catastrophic already in the 20th. Unable to withstand the competition with livestock, which were grazed in the fields of bucardo habitat, the ibex began to die out.

The last Iberian Ibex died in an accident in 2000. On January 6, the female Celia was found under a tree that had fallen on her. Scientists tried to restore the extinct species in 2009 by resorting to cloning, but the born bucrado cub lived for only 7 minutes.

Black Faced Hawaiian Flower Girl (2004)

The Hawaiian Islands have become a habitat for a large number of species of finches. In total, scientists counted 22 species of Hawaiian flower girls, seven of them are now on the verge of extinction, and nine are lost forever. Last on the list of extinct was the Black-faced Hawaiian flower girl, which was recognized as lost in 2004.

This species was discovered only in 1973, and even then it was recognized as endangered. In captivity, there were no more than 200 representatives of the species.

The black-faced Hawaiian flower girl is one of the few species in which humans have not been implicated in extinction. The reason for the extinction of birds was the disease that came with mosquitoes that appeared on the islands, and the natural reduction in the area of ​​fodder plants.

Great White Butterfly of Madeira (2007)

The only habitat of the Madeira Great White Butterfly was the forests of Laurisilva on the island of Madeira. The species was officially declared extinct in 2007.

The reason for the disappearance of the Great White Butterfly of Madeira was the progressive 20th century. Deforestation, construction of enterprises, pollution of nature - all this added to the list of extinct animals and the Madeira butterfly.

Chinese River Dolphin (2007)

The next representative of the list of extinct animals can still be resurrected from the "dead". Declared extinct in 2007, the Chinese river dolphin was spotted by a Chinese fisherman and captured on video. After reviewing the film, the scientists concluded that it could be a representative of a lost species, but they did not "resurrect" the unique dolphin.

Chinese river dolphins have become a target for fishermen because of their gullibility. Mammals were not afraid to swim close to the shores. The fact that the Chinese have long considered animals to be river goddesses did not save dolphins from human ignorance.

Caribbean monk seal (2008)

Least of all, scientists did not want to recognize the Caribbean monarch seal as an extinct animal. The last time representatives of this species of monarch seals were seen back in 1952, but officially it received the status of extinct only in 2008.

The Caribbean monarch seal inhabited the coast and islands of the Caribbean Sea and the Gulf of Mexico from Honduras and Yucatan, in the east to Jamaica, Cuba and the Bahamas. Along with the Caribbean monarch seal, the ticks that lived only in its nose also died out.

West African Black Rhino (2011)

In 2011, the extinct animals were replenished with a representative of the rhinoceros family - the West African black rhinoceros. This species of rhinoceros was the most numerous in the family, a sharp decline was recorded in the 1970s. Poachers caught animals and sold the horn on the black market, because, according to legend, the horn of the West African black rhinoceros has healing properties.

By 1995, about 2500 rhinos remained, by 2000 - 10, and in 2001 there were 5. The last individual was seen in Cameroon in 2006. Since then, experts could not find a single representative of this subspecies.

Galapagos tortoise (2012)

Until 1972, this species of giant tortoise was considered extinct, but the last representative of the Galapagos tortoises was discovered on the uninhabited Pinta Peninsula.

A male named Lonesome George settled in the Galapagos National Park for 40 years. All attempts to restore the view ended in failure. On June 24, 2012, reserve keeper Fausto Llereno, who had been looking after the unique turtle for 40 years, found Lonely George dead. At the time of his death, George was 100 years old, by the standards of giant turtles - the prime of his life.

The Spaniards were unable to clone the Iberian ibex, but they do not give up hope one day to resurrect the extinct species.

The Iberian ibex, Capra pyrenaica pyrenaica, is a variety of the Spanish Capricorn Capra pyrenaica. Scientists believe that this subspecies became completely extinct in 2000. However, the biologists were left with frozen cells taken from the ear of the last of famous capricorns writes the Independent.

To create the embryos, experts at the University of Zaragoza used the eggs of domestic goats, which were also used as surrogate mothers. During the experiment, scientists created 439 embryos, of which 57 were planted in goats.

However, the experiment failed: the newborn kid died immediately after birth due to breathing problems. At the same time, previous attempts to clone the Pyrenean ibex have failed by even more early stage: in 2003, two pregnancies ended in premature miscarriages.

Nevertheless, scientists were convinced that the method they chose would sooner or later bring results. Project manager Jose Folch said that the resulting hybrid is almost completely identical to the Pyrenean ibex.

The genetic material now being used to recreate the Pyrenean ibex comes from a 13-year-old female captured in 1999.

Crossing representatives of closely related species is an extreme, but often the only way to save endangered animals. It is sometimes resorted to when several representatives of the same sex remain alive from the whole species. Then, after a series of selection crosses, it is possible to achieve almost complete correspondence of the offspring to the desired animal. However, in the case of Spanish scientists, the task is complicated by the fact that there are no living representatives of the ibex at all - and it is impossible to carry out a series of crosses. Therefore, there was no guarantee that the resulting offspring would be at least to some extent similar to the wild species. Spanish scientists considered their experiment successful precisely because they were able to achieve a likeness of a goat to its extinct ancestor.

mountain goats

Mountain goats, Capra, are close relatives of rams and sheep. The genus includes animals of medium size, the body of which is densely folded, the neck is thickened, the head is relatively short, the forehead is convex, wide. The horns of males are large, in different species they are very diverse in shape and structure, in females they are small and more of the same type; at the root they are compressed from the sides, so that the longitudinal diameter is greater than the transverse one, equipped with transverse ridges in front and strongly bent backwards; the tail is short, triangular in shape, devoid of hair on the lower surface, usually raised. The ears are quite large, very mobile, pointed at the ends.

All goats are typically mountain animals, inhabiting hard-to-reach rocky places, steep slopes of cliffs, gorges and avoiding any vast open and level spaces. Distributed up to a height of 5.5 thousand meters above sea level.

The Iberian ibex, a species of mountain goat, was officially declared extinct in 2000 when the last member of the species was found dead in northern Spain. Shortly before this incident, scientists managed to preserve tissue samples of this animal, which lived in mountain ranges throughout the country, in liquid nitrogen.

Using DNA extracted from these samples, scientists were able to replace the genetic material in the eggs of domestic goats and clone a female Pyrenean goat, also known as bucardo. Thus, the first cloning of a representative of an extinct species took place.

Unfortunately, the kid died shortly after birth due to a physical defect in his lungs. Other cloned animals, even sheep, had a similar deficiency at birth.

But the breakthrough has given scientists hope that endangered and recently extinct species could be resurrected from frozen tissues. The chances have also increased that one day it will be possible to talk about the return to life of even such long-extinct species as mammoths or even dinosaurs.

Dr. José Folch from the Aragonese Center for Technology and Food Research in Zaragoza, northern Spain, teamed up with his colleagues from the Madrid National Research Institute for Agriculture and Food and began the study.

“The newborn goat was genetically identical to Bucardo,” he says. “In the case of species such as bucardos, cloning is the only measure that can save them from complete extinction.”

The Iberian goats, which have distinct curved horns, were once abundant in northern Spain and the French Pyrenees, but constant hunting in the 19th century reduced their population to less than 100.

As a result, protection was declared over them in 1973, but by 1981 only 30 individuals remained living on a piece of land - in the Ordes National Park, in the autonomous region of Aragon. The last bucardo, a thirteen-year-old female named Celia, was found dead near the French border by park rangers in January 2000. The skull of the animal was crushed.

Dr. Folch and his colleagues, sponsored by the government of Aragon, managed to catch a bucardo a year earlier and take a skin sample from his ear for cryopreservation.

Using technology similar to that used to clone Dolly the sheep, known as nuclear transfer, researchers were able to implant bucardo DNA into eggs taken from domestic goats and create 439 embryos, 57 of which were implanted in surrogate wombs.

Only seven operations ended in pregnancy and only one goat eventually gave birth to a female bucardo, who died seven minutes after birth from problems with respiratory system caused, most likely, by a flaw in the DNA used.

Despite the unsuccessful cloning and the death of the cloned goat, many scientists believe that this approach may be the only way to save species that are on the verge of extinction.

Research by Japanese geneticist Teruhiko Wakayama gives hope that even very long-extinct species can be resurrected: he managed to produce healthy clones from a mouse frozen 16 years ago.

But attempts to return animals such as the mammoth or even the dodo are doomed to many complications. Even DNA frozen in ice gradually deteriorates, leaving holes in the genetic information needed to produce a healthy animal.

However, last year scientists unveiled the near-complete genome of a mammoth that went extinct about 10,000 years ago, sparking a storm of controversy over possible mammoth DNA synthesis.

Professor Robert Miller, director of the Medical Research Council at the Department of Reproductive Sciences at the University of Edinburgh, is working with the Royal Zoological Society of Scotland to clone rare African mammals, including the white rhino.

They founded the Rare and Endangered African Mammal Breeding Institute in the hope that with the help of breeding technology they could save species such as the Ethiopian wolf, wild dog and pygmy hippopotamus.

“I think this is an outstanding achievement, because it shows the potential for the resurrection of extinct species,” says Professor Miller. “Of course, there is still a lot of work to be done before the method becomes effective, but advances in this area will bring us many solutions.”

Dozens of projects around the world are already working to collect tissue and DNA from endangered species. The Zoological Society of London and the National History Museum have founded the Frozen Ark project, which aims to preserve the DNA of thousands of animal species before they completely disappear.

On July 30, 2003, a group of Spanish and French scientists turned back time. They brought an extinct animal back to life - however, it again disappeared into oblivion before their eyes. The animal they "revived" was a subspecies of the Pyrenean ibex ( Caprapyrenaicapyrenaica) and was called bucardo. It was a large (weighing up to 100 kilograms) beautiful beast, wearing gracefully curved horns. For tens of thousands of years, he lived in the Pyrenees - the mountains that separate Spain from France, climbed the cliffs, fed on the leaves and stems of plants, experienced harsh winters.

The idea of ​​the return of extinct species to life - some call it extinction - teeters on the verge of reality and science fiction for over two decades.

Then man invented the gun. For several centuries, hunters have almost exhausted the bucardo. In 1989, Spanish scientists conducted a study that showed that only a dozen of the Pyrenean ibexes of this subspecies remained. A few years later, a single bucardo was running in the mountains - a female named Celia. Employees national park Ordesa and Monte Perdido, led by the director, veterinarian Alberto Fernandez-Arias, trapped Celia, radio-collared her and set her free. Nine months later, the radio collar began to send long steady signals: a sign that Celia was dead. She was found crushed under the trunk of a fallen tree. Bucardo was officially declared extinct. However, Celia's cells were preserved in the laboratories of Zaragoza and Madrid. Over the next few years, a team of reproductive physiologists led by José Folch tried to inject nuclei from these cells into goat eggs purified from their own DNA, and then implant the resulting eggs into surrogate mothers. 57 such attempts caused pregnancy in only 7 cases, of which 6 ended in miscarriages. However, one mother, a cross between another subspecies of the Pyrenean ibex ( Caprapyrenaicavictoriae) and a domestic goat, managed to bear the cub in due time. Thanks to a caesarean section performed by Folch and his colleagues, a cloned female weighing 2.5 kilograms was born. Holding the newborn in his arms, Fernandez-Arias watched as she struggled to take a breath, frantically sticking out her tongue. Despite all attempts to help her, the goat died ten minutes later. An autopsy showed that one of her lungs had grown a huge extra lobe, as hard as a piece of liver. It was completely impossible to save the newborn. Bucardo is just one of the animals exterminated - sometimes intentionally - by man. But at least this is a subspecies (there are two others left). But the dodo, wingless auk, marsupial wolf, Chinese river dolphin, passenger pigeon and American royal woodpecker have disappeared altogether. Today, many other species are also threatened with extinction, and it is hardly worth hoping that the bucardo will become the last extinct animal. Fernandez-Arias belongs to a small but active cohort of scientists who believe that cloning can break the sad tradition. The idea of ​​the return of extinct species to life - some call it extinction - has teetered on the edge of reality and science fiction for more than two decades, ever since writer Michael Crichton released dinosaurs from the Park jurassic". And for quite a long time, fantasy was noticeably ahead of science. No one has ever come closer to true extinction than the scientists who cloned Celia. Since then, Fernandez-Arias has been impatiently waiting for science to finally catch up with science fiction, and people will be able to return animals that have been driven to extinction from oblivion. “Now that moment has come,” the scientist told me. I met Fernandez-Arias in October 2012 at the Forward to the Past closed science meeting at the National Geographic Society headquarters in Washington DC. This was the first ever meeting of geneticists, biologists, conservationists environment and on Ethics, where issues of revival of extinct species were discussed. How likely is a positive result? And should it be done at all? One by one, scientists reported startling advances in stem cell cloning, the restoration of ancient DNA, and the reconstruction of lost genomes. The farther, the greater the excitement seized the audience. There was a general impression: the revival of extinct species is by no means a fantasy. “Progress in research has gone a lot further, and it happened much faster than anyone could have imagined,” says Ross McPhee, curator of the Mammals Department at the American Museum. natural history in New York. “Now we have to think about why, in fact, we need to bring extinct species back to life.” In Jurassic Park, dinosaurs were brought to life for the entertainment of people. The catastrophic consequences described in the novel and shown in the film cast a shadow on the idea of ​​extinction, or rather, on its perception among the townsfolk, who are much easier to scare than to teach anything. Therefore, do not forget that "Jurassic Park" is just a masterfully crafted fantastic thriller. In fact, we can count on the revival of only those species that became extinct no earlier than a few tens of thousands of years ago and in the remains of which whole cells were preserved, or, in extreme cases, enough DNA to be able to reconstruct the genome of the animal. Due to these natural causes, we will never be able to completely restore the genome of a Tyrannosaurus rex that disappeared about 65 million years ago. All species that could theoretically be resurrected disappeared into oblivion at a time when humanity was rapidly moving towards establishing dominance over the world. First of all, what has been said refers to the recent past, when it was we humans who became one of the reasons for the extinction of many species of living beings, hunting them, destroying their habitat or spreading diseases. This, incidentally, is one of the arguments in favor of the return of extinct species to life.

Over the past ten years, cloning has become less risky.

“If we are talking about species that we have exterminated, then I think we have an obligation to try to bring them back,” says Michael Archer, a paleontologist at the University of New South Wales who has championed the idea of ​​extinction for many years. According to opponents of this idea, the resurrection of an extinct species would be tantamount to trying to take the role of God. In Archer, such arguments cause a grin: “I think we swung at the role of God when we destroyed these animals.” Other scientists who advocate de-extinction argue that it could bring concrete benefits. Biological diversity is a pantry of inventions of nature. Majority medicines, for example, were not created by people from scratch, but developed on the basis of natural compounds contained in wild plants which may also die. And some animals of past eras played an important role in their ecosystems. And these ecosystems will certainly benefit from their return. Say, 15 thousand years ago, mammoths and other large herbivores lived in Siberia. Then this area was not a moss-covered tundra, but steppe forbs. Sergey Zimov, geophysicist and director of the North-Eastern Scientific Station Russian Academy science, located in the lower reaches of the Kolyma River, long ago came to the conclusion that this coincidence is not accidental: mammoths and other herbivores supported the very existence of the steppe, loosening the soil and fertilizing it with their excrement. When they disappeared, the moss replaced the grass, turning the steppe into an infertile tundra. AT last years Zimov is trying to turn back the clock by bringing bison, horses, musk oxen and others into the tundra, to the area he calls the Pleistocene Park. large mammals. He would be happy if they began to roam freely here again. woolly mammoths. “But only my grandchildren will see them,” Zimov says. - It is mice that breed quickly, and mammoths - very slowly. Will have to wait". Ten years ago When Fernandez-Arias tried to bring the bucardo back to life, he had at his disposal deplorably crude instruments by today's standards. Only seven years have passed since the birth of Dolly the Sheep, the first large cloned mammal. In those years, scientists cloned an animal by extracting DNA from one of its cells and injecting it into the egg of another individual, purified from its own genetic material. In order for the cell to start dividing, there was enough electrical discharge. The developing embryo was then implanted into a surrogate mother. The vast majority of pregnancies thus induced ended in miscarriage, and the few clones born were overcome by congenital diseases. Over the past ten years, cloning has become less risky. In addition, scientists now understand how to return the cells of adult animals to their original state so that they become similar to embryonic ones. After that, their development can be directed so that they turn into any kind of cells - including sperm and eggs. The latter are then encouraged to develop into full-fledged embryos. Thanks to this kind of technical trick, it has become, if not easier, then practically possible to bring a recently extinct species back to life, for example, a passenger pigeon. In 1813, traveling down the Ohio River from Hardensburg to Louisville, naturalist John James Audubon observed one of the most wonderful natural phenomena of its time: a flock of passenger pigeons (Ectopistes migratorius) that covered the sky. "The air was literally the words are filled with doves,” he later wrote. - The midday light faded, as from a solar eclipse, droppings flew to the ground, like flakes wet snow; the incessant noise of flapping wings put me to sleep.” When Audubon reached Louisville at sunset, the pigeons were still flying—and continued to fly for the next three days. "All locals were hung with weapons,” wrote Audubon. “The banks of the river were filled with men and boys who continuously shot at the wanderers… Many were killed.” In 1813, it was difficult to imagine a species that would be less threatened with extinction. Nevertheless, by the end of the century, the number of the red-breasted passenger pigeon was catastrophically reduced due to the decrease in the area of ​​\u200b\u200bforests where it lived, and ruthless extermination. In 1900, the last pigeon seen in the wild was shot by a boy with a blowgun. And in 1914, only a century after Audubon marveled at the clouds of these birds, the last captive passenger pigeon died at the Cincinnati Zoo - a female named Martha, named after the wife of President George Washington. Author and environmentalist Stuart Brand, known among other things for founding the Whole Earth Catalog in the late 1960s, grew up in Illinois and loved hiking in those same forests, who, just a few decades earlier, had heard the flapping of the wings of passenger pigeons. “Their habitat was my habitat,” he says. Two years ago, Brand and his wife Ryan Phelan, founder of DNA Direct, a private genetic testing company, wondered if the species could be brought back to life. One evening, while having dinner with the genetic engineer George Church at Harvard Medical School, Stuart and Ryan realized that he was thinking along the same lines.

The Tasmanian wolf, Australia's largest marsupial predator, may be able to be resurrected much faster than a passenger pigeon or a mammoth.

Church knew that conventional cloning methods would not work with pigeons, since bird embryos develop in eggs, and no museum specimen of a passenger pigeon (including the stuffed Martha that is kept at the Smithsonian) appears to be the intact genome could be preserved. However, Church was able to suggest another way to recreate the bird. DNA fragments have been preserved in museum samples. By connecting these fragments, scientists will be able to read about a billion letters from the passenger pigeon genome. While George Church is not ready to synthesize an entire animal genome from almost nothing, however, he has invented a technology that allows him to build large fragments of DNA in any sequence he wants. Theoretically, he could create genes that are responsible for certain traits inherent in the passenger pigeon - say, a gene for his long tail, - and insert them into the genome or stem cell of a common rock dove. Cesar stem cells containing this altered genome could be transformed into germ cells. They, in turn, should be introduced into eggs laid by the rock dove, where they would move into the developing reproductive organs of the embryo. The chicks hatched from these eggs would look like normal rock doves - but would produce eggs and sperm containing altered DNA. When the chicks grow up, mate and lay eggs, they hatch into birds with traits unique to the passenger pigeon. These pigeons can then be crossbred, gradually breeding birds more and more like the extinct species. Church's genome rewiring method could theoretically be applied to any species that has a living close relative and a genome that can be reconstructed. Although the idea of ​​revitalization a passenger pigeon or even a mammoth can no longer be called a crazy fantasy, more than one year must pass before its realization. Another extinct species may be able to be resurrected much faster. The animal about which in question, is the scientific passion of a group of Australian scientists led by Michael Archer, who calls his endeavors the "Lazarus Project". Previously, Archer ran a highly publicized cloning project. tasmanian wolf, or tiger, Australia's largest marsupial carnivore, which became extinct in the 1930s. Although this unfortunate event happened quite recently, Archer managed to get hold of only a few fragments of the animal's DNA. Archer's experiments generate massive interest and an atmosphere of feverish anticipation. However, Archer and his colleagues at the Lazarus Project decided not to reveal their secrets until the work began to bring tangible results. Maybe the time has come? In early January, the Lazarus Project announced that they were trying to resurrect two closely related species of Australian water frogs (Rheobatrachus vitellinus and R. silus). Before disappearing in the mid-1980s, these frogs bred in the same amazing way. The female spawned a cloud of eggs, which the male fertilized, after which the female swallowed them. The hormone contained in the eggs stopped the secretion of gastric juice in the female. In fact, her stomach turned into a uterus. A few weeks later, the female opened her mouth and spewed ready-made frogs into the light. Because of these miracles of childbearing, these amphibians are also called caring frogs. Unfortunately, soon after the researchers began to study them, caring frogs disappeared. “Just when they were here, then the scientists came back and they are gone,” says Andrew French, a cloning specialist at the University of Melbourne who works on the Lazarus Project. Bringing the frogs back from oblivion, the project participants use the most modern methods cloning to insert the nucleus of a caring frog cell into the eggs of other Australian amphibian species, devoid of their own genetic material. Things move slowly, because unfertilized frog eggs begin to deteriorate within a few hours after being thrown, and they cannot be frozen to revive them later. Therefore, for experiments, fresh caviar is needed, which frogs throw once a year, during short period breeding. Be that as it may, scientists have managed to achieve some success. “Suffice it to say that we actually have the embryos of these extinct animals,” says Archer. “We have come a long way already.” The researchers are convinced they just need more quality eggs to go even further. “At this stage, it's all about quantity,” French says. The miracle of childbearing in caring frogs makes you think about what we lose when another species disappears. But does this mean that we should revive extinct species? How much richer will the world be if frogs live in it, growing tadpoles in their stomachs? The benefit, French argues, is straightforward: for example, studying these frogs could enrich us with important knowledge about ectopic pregnancy, which may one day help develop treatments for infertile pregnant women. However, many scientists see the resuscitation of extinct animals as a distraction from the vital work of preventing new mass extinctions. "It's clear that a huge effort is needed to save endangered species," says John Vince, an evolutionary biologist at New York's Stony Brook University. - But there is no special need to bring back already extinct species to life, as it seems to me. Why invest millions of dollars in resurrecting a few species from the dead when there are millions of other species waiting to be discovered, described, and preserved?” Adherents of the idea of ​​extinction respond that cloning and genetic engineering technologies, which are developing in the process of reviving extinct animals, may help conservation in the future. rare species, especially those that do not breed well in captivity. And while the latest biotechnologies can be quite expensive, they tend to fall in price very quickly. “Perhaps some thought that the development of a polio vaccine would detract from the creation of artificial lungs,” says George Church. “It is difficult to predict in advance which path will eventually turn out to be false, and which one will be saving.” But what exactly are we ready to call salvation? Even if Church and his colleagues manage to recreate every single feature of a passenger pigeon in a rock dove, will the resulting bird actually be a passenger pigeon - or just a man-made curiosity? If Archer and French succeed in producing one single caring frog, will that mean they have revived the species? If this frog does not have a mating partner, it will become Celia's amphibious counterpart, and its species will, in fact, remain extinct. Will it be enough to keep a frog brood in a laboratory or zoo where the public will stare at them, or will they need to be reintroduced into their original habitats in order for the species to actually be considered resurrected?

Even if the extinction is successful from all points of view, the difficulties will not end there.

"The history of species returning to the wild after a wild population goes extinct is full of examples of insurmountable difficulties," says Stuart Pimm, a conservationist at Duke University. Enormous efforts, for example, have been made to reintroduce the Arabian oryx. However, when these antelopes were released into a reserve in Central Oman in 1982, almost all of them were quickly killed by poachers. “We had animals, and we returned them to nature, but the world was not ready for this,” Pimm laments. “The resurrection of the species only solves one, tiny part of the problem.”

Poaching is not the only danger threatening resurrected species. For many of them, there are no places left to call home. The Chinese river dolphin has become extinct due to water pollution in the Yangtze and other effects of human activity. Since then, the river has not become cleaner. Frogs are rapidly disappearing all over the world due to chytridiomycosis. This fungal disease is spread due to the uncontrolled animal trade. If Australian biologists ever release the caring frogs into the mountain streams where they once lived, they could become infected again and become extinct.

“In the event that there is no natural environment in which it would be possible to release the resurrected species, the whole idea of ​​resurrecting it is nothing but a senseless waste big money," says Glenn Albrecht of Australia's Murdoch University in Perth.

Even if the extinction is successful from all points of view, the difficulties will not end there. Let's say passenger pigeons find wonderful living conditions in the resurgent forests of the eastern United States. But will they not become carriers of some virus that will exterminate another species of birds? And how will the inhabitants of American cities react to the appearance of pigeon flocks that will block the sky and flood the streets with droppings?

Hank Greely, a bioethicist at Stanford University, has a keen interest in researching the ethical and legal aspects of extinction. Yet for him and many others, the very fact that science can bring extinct species back to life is already a compelling reason to welcome de-extinction rather than condemn it. “After all, this is actually very cool! Greeley says. - Saber-toothed tiger, you say? I would like to see a live saber-toothed tiger!”

Extinction is a natural process: typical species become endangered within 10 million years after their appearance on Earth. But today, when the planet is facing a number of serious problems, such as overpopulation, pollution, climate change, etc., the loss of species is happening thousands of times faster than it would be natural.

It is difficult to know exactly when certain species will disappear from the wild, but it is safe to say that thousands of animal species become extinct every year.

In this article, we offer a look at the recently extinct animals that we will miss the most. From the Javan tiger and the Caribbean monk seal to the Mauritian dodo (or dodo), here are 25 extinct animals we won't see again.

25. Madagascar pygmy hippopotamus

Once widespread on the island of Madagascar, the Madagascar pygmy hippo was a close relative of the modern hippo, albeit much smaller.

Initial estimates suggested that the species had gone extinct for about a thousand years, but new evidence has shown that these hippos may have lived in the wild until the 1970s.

24. Chinese river dolphin


Known by many other names such as "baiji", "yangtze river dolphin", "white-finned dolphin" or "yangtze dolphin", the Chinese river dolphin was a freshwater dolphin that lived in the Yangtze River in China.

The population of Chinese river dolphins declined sharply by the 1970s as China began to make heavy use of the river for fishing, transportation, and hydroelectric power. The last known surviving Chinese river dolphin, Qiqi, died in 2002.

23. Long-eared kangaroo


Discovered in 1841, the long-eared kangaroo is an extinct species of the kangaroo family that lived in southeastern Australia.

It was a small animal, slightly larger and slimmer than its living relative, the red hare kangaroo. The last known specimen of this species was a female taken in August 1889 in New South Wales.

22. Javan tiger


Once common on the Indonesian island of Java, the Javan tiger was a very small subspecies of the tiger. During the 20th century, the population of the island increased many times, leading to massive clearing of forests, which were turned into arable land and rice fields.

Habitat pollution and poaching have also contributed to the extinction of this species. The Javan tiger has been considered extinct since 1993.

21. Steller's cow


Steller's cow (or sea cow, or cabbage) is an extinct herbivore marine mammal, which once abounded in the North Pacific.

It was the largest representative of the siren squad, which includes its closest living relatives - the dugong and the manatee. Hunting Steller cows for meat, skin and fat has led to their complete extermination within just 27 years since the discovery of the species.

20. Taiwan Clouded Leopard

The Taiwanese clouded leopard was once endemic to Taiwan and a subspecies of the clouded leopard, a rare Asian cat thought to be an evolutionary link between large and small cats.

Excessive logging has destroyed the animal's natural habitat, and the species was declared extinct in 2004 after 13,000 camera traps showed no sign of Taiwan's clouded leopards.

19. Red gazelle

The red-headed gazelle is an extinct species of gazelle believed to have lived in the rainfall-rich mountainous regions of North Africa.

This species is known only by three individuals acquired in the markets in Algeria and Oman, north of Algeria, at the end of the 19th century. These copies are kept in museums in Paris and London.

18. Chinese paddlefish


Sometimes also called "Psephur", the Chinese paddlefish was one of the largest freshwater fish. Uncontrolled overfishing and destruction of natural habitats put the species at risk of extinction in the 1980s.

The last confirmed sighting of this fish was in January 2003 in the Yangtze River, China, and the species has since been considered extinct.

17. Labrador eider


The Labrador Eider is believed by some scientists to have been the first endemic species birds North America, which disappeared after the Columbus Exchange.

It was already a rare bird before the arrival of European settlers, and became extinct shortly thereafter. The females were grey, while the males were black and white. The Labrador Eider had an elongated head with small beady eyes and a strong beak.

16. Pyrenean ibex


Once endemic to the Iberian Peninsula, the Iberian ibex was one of the four subspecies of the Spanish ibex.

In the Middle Ages, the wild goat abounded in the Pyrenees, however, the population rapidly declined in the 19th and 20th centuries due to uncontrolled hunting. In the second half of the 20th century, only a small population survived in this region, and in 2000 the last representative of this species was found dead.

15. Mauritian dodo, or dodo


is an extinct flightless bird that was endemic to the island of Mauritius in the Indian Ocean. According to subfossil remains, Mauritian dodos were about a meter tall and may have weighed up to 21 kg.

O appearance Mauritian dodos can only be judged by drawings, images and written sources, so the life-time appearance of this bird is not known for certain. Dodo in popular culture is used as a symbol of extinction and the gradual disappearance of the species.

14. Orange toad


Orange toads were small, up to 5 cm long, toads that used to be found in a small high mountain region. north of the city Monteverde, Costa Rica.

The last living individual of this animal was discovered in May 1989. Since then, no signs have been recorded confirming their existence in nature. The sudden extinction of this beautiful frog may have been caused by a fungus of the class Chytridiomycetes and extensive habitat loss.

13. Choiseul pigeon

Sometimes also referred to as the crested thick-billed pigeon, the Choiseul pigeon is an extinct species of pigeon that was endemic to the island of Choiseul in the Solomon Islands, although there are unconfirmed reports that members of this species may have lived on some nearby islands.

The last documented sighting of a Choiseul pigeon was in 1904. It is believed that these birds became extinct due to predatory extermination by cats and dogs.

12. Cameroonian black rhinoceros


As a subspecies of the critically endangered black rhino, the Cameroonian black rhinoceros was once widely distributed throughout many African countries, including Angola, Kenya, South Africa, Ethiopia, Chad, Rwanda, Botswana, Zambia and others, however, irresponsible hunting and poaching reduced the population of this amazing animal by 2000 to just a few last individuals. In 2011, this subspecies of rhino was declared extinct.

11. Japanese wolf


Also known as the Ezo wolf, the Japanese wolf is an extinct subspecies of the common wolf that once inhabited the coasts of Northeast Asia. Its closest relatives were North American wolves rather than Asiatic wolves.

The Japanese wolf was extirpated from the Japanese island of Hokkaido during the Meiji Restoration, when American-style agricultural reforms were accompanied by the use of strychnine bait to kill predators that posed a threat to livestock.

10 Caribbean Monk Seal


Nicknamed "the sea wolf", the Caribbean monk seal was close-up view seals inhabiting the Caribbean. The overhunting of seals for blubber and the depletion of their food sources are the main causes of the species' extinction.

The last confirmed sighting of a Caribbean monk seal dates back to 1952. These animals were not seen again until 2008, when the species was officially declared extinct after a five-year search for survivors that ended in nothing.

9 Eastern Cougar


The eastern cougar is an extinct species of cougar that once lived in northeastern North America. The eastern cougar was a subspecies of the North American cougar, a large cat that inhabited much of the United States and Canada.

Eastern cougars were declared extinct by the US Fish and Wildlife Service in 2011.

8. Great Razorbill

The great auk was a large flightless auk that became extinct in the middle of the 19th century. Once widespread throughout the North Atlantic, from Spain, Iceland, Norway and the UK to Canada and Greenland, this beautiful bird has been extirpated by man for its down, which was used to make pillows.

7. Tarpan


Also known as the Eurasian wild horse, the tarpan is an extinct subspecies of the wild horse that once lived across much of Europe and parts of Asia.

Since tarpans were herbivores, their habitat was continuously decreasing due to the growing civilization of the Eurasian continent. Combined with the incredible extermination of these animals for their meat, this led to their complete extinction at the beginning of the 20th century.

6. Cape Lion

An extinct subspecies of the lion, the Cape lion lived along the Cape Peninsula at the southern tip of the African continent.

This majestic big cat disappeared very quickly after the appearance of Europeans on the continent. Dutch and English colonists and hunters simply exterminated this species of animals at the end of the 19th century.

5 Falkland Fox


Also known as the varra or the Falkland wolf, the Falkland fox was the only native land mammals Falkland Islands.

This endemic of the canine family became extinct in 1876, becoming the first known canid to become extinct in historical times. This animal is believed to have lived in burrows, and its diet consisted of birds, larvae and insects.

4. Reunion giant turtle


Endemic to Reunion Island in the Indian Ocean, the Reunion giant tortoise was a large tortoise up to 1.1 meters long.

These animals were very slow, curious and not afraid of people, which made them easy prey for the first inhabitants of the island, who exterminated turtles in huge numbers - as food for people, as well as pigs. The Réunion giant tortoise became extinct in the 1840s.

3. Kiyoa


The kyoea was a large, up to 33 cm long, Hawaiian bird that became extinct around 1859.

The kyoea was a rare bird even before it was discovered. Hawaiian Islands Europeans. Even the native Hawaiians did not seem to know about the existence of this bird.

Only 4 specimens of this beautifully colored bird have been preserved in different museums. The reason for their extinction is still unknown.

2. Megaladapis

Informally known as koala lemurs, megaladapis are an extinct genus of giant lemurs that once inhabited the island of Madagascar.

To clear the place, the first settlers of the island burned local dense forests, which were natural environment habitats of these lemurs, which, combined with over-hunting of the animal, has greatly contributed to the extinction of these slow-moving animals.

1. Quagga


The quagga is an extinct subspecies of the savannah zebra that lived in South Africa until the 19th century.

Since these animals were fairly easy to track down and kill, they were hunted en masse by the Dutch colonists (and later the Boers) for their meat and skins.

Only one single quagga was photographed during his lifetime (see photo), and only 23 skins of these animals have survived to this day.