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De-extinction -

The process of reviving extinct species through various scientific methods is known as “de-extinction.” Scientists are driven with the aim to restore lost biodiversity, ecosystems, and species to our world.

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Early cloning experiments -

The first serious attempts to bring back extinct species began with cloning technologies. In 1996, Dolly the sheep became the first mammal to be cloned, which demonstrated for the first time that cloning of complex organisms was possible.

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Pyrenean ibex -

The Pyrenean ibex (a type of wild mountain goat) is considered the closest scientists have come to de-extinction. It went extinct in 2000, but in 2003 Spanish scientists used preserved tissue to clone a Pyrenean ibex. Unfortunately, the cloned animal died shortly after birth.

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CRISPR -

After the 2000s, technology has seen the rise of powerful genetic editing tools that allow scientists to precisely modify DNA sequences. One of these tools is CRISPR, which allows scientists to add, remove, or alter specific genetic material in an animal’s DNA.

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Genetic technologies -

With the rise of these gene-editing technologies, scientists can now precisely manipulate DNA to recreate extinct animals. They allow researchers to insert key genetic traits from extinct species into closely related living species, which is a critical step in de-extinction.

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A question of why -

Scientists aim to bring back extinct species to restore ecological balance, preserve biodiversity, and potentially reverse some of the damage humans have done to ecosystems.

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Ecological restoration -

Many extinct species were critical to their ecosystems. By reintroducing them, scientists hope to restore natural habitats. The woolly mammoth, for example, would be reintroduced to tundra regions to maintain grassland ecosystems.

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The Woolly Mammoth Revival Project -

Scientists are trying to use Asian elephants' DNA mixed with genes from the woolly mammoth to create a hybrid species that could thrive in cold environments. This combination is known as “back-breeding.”

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Frozen DNA -

The woolly mammoth, which died out roughly 10,000 years ago, had its DNA preserved in the frozen Arctic tundra, which scientists have since uncovered.

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Passenger pigeons -

The woolly mammoth isn’t the only animal on the list of potential revivals. The passenger pigeon, once one of the most populous birds in North America, went extinct in the early 20th century. Scientists are now working to bring it back by editing the genome of the band-tailed pigeon, its closest living relative, to resemble the extinct species.

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Moa -

The moa, a giant flightless bird from New Zealand, went extinct around 500 years ago, and scientists are also studying ancient DNA for the possibility of bringing it back.

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Thylacines -

The Tasmanian tiger, or thylacine, went extinct in the 20th century due to human colonization. Scientists are now investigating the possibility of bringing it back through de-extinction, using preserved DNA from museum specimens and closely related species.

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Preserved DNA -

The Tasmanian tiger’s DNA has been preserved in alcohol since before the species went extinct. This specimen has been the holy grail that scientists have been using to try and reignite the lost animal.

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Long lost -

The issue with preserving DNA is that it degrades over time, until eventually there isn’t enough left to revive the species. This is why dinosaurs can never be brought back.

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Aurochs -

Scientists are also attempting to bring back aurochs, the wild ancestor of modern cattle, which went extinct in the 1600s. This project could restore lost ecosystems in Europe.

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The great auk -

The great auk, a large flightless bird, was hunted to extinction in the 19th century. Scientists are studying its DNA with the hope of bringing it back using gene-editing technologies.

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Quagga -

The quagga, a subspecies of zebra, went extinct in the late 19th century. Through selective breeding of zebras with quagga-like traits, scientists have successfully bred animals that resemble the quagga, proving that selective breeding can be a path toward de-extinction.

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Millions of variables -

In order to back-breed an extinct species with a living one, scientists need to make millions of edits to DNA sequences. This used to be near-impossible, but modern technology has brought humanity one step closer to succeeding.

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Cells -

Another avenue that scientists have been researching is to clone a dead animal by taking part of an intact cell and transferring it to the egg of a close living relative, all in the hopes that an embryo would form.

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Gestation -

The embryo would then be inserted into a living relative of the extinct animal, and the new hybrid would gestate for the required period. For the woolly mammoth, an elephant would gestate for 18 to 22 months.

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Dying off -

However, this method is made difficult by the fact that cells die very quickly after an animal has perished, and so many species cannot be brought back like this.

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Ethical concerns -

There are ongoing debates regarding the ethics of bringing species back from extinction. Critics argue that resources should focus on saving endangered species rather than reviving extinct ones, while others worry about the potential ecological risks of reintroducing long-lost species.

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Potential risks -

Reintroducing extinct species could have unintended ecological consequences. These animals may not fit into modern ecosystems, they might compete with current species, or they may even introduce new diseases.

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Long-lost habitats -

Some species, like the woolly mammoth, wouldn’t fit properly into our modern world, because the habitats they once occupied do not exist anymore.

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Disease control -

Some scientists believe that reintroducing extinct species could actually help control diseases rather than boost them. For example, the woolly mammoth’s return to the Arctic could prevent the thawing of permafrost, which could otherwise release ancient diseases as the climate warms.

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“Playing God” -

De-extinction raises moral and ethical questions, including whether humans should interfere with nature in such profound ways. Some argue that bringing back extinct species could lead to unforeseen consequences, while others believe it is our responsibility to right past wrongs.

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Endangered species -

Many scientists have argued that the technology used to bring past animals back from extinction could also help prevent other animals from becoming extinct in the future. Many endangered species qualify for this.

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The future of de-extinction -

As technology advances, the potential for de-extinction grows. Scientists are considering a variety of species for revival, including the saber-toothed tiger and the giant ground sloth. The ultimate goal is to use de-extinction as a tool to help rebuild ecosystems worldwide.

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Public perception -

Public opinion on de-extinction is mixed. Some view it as an exciting scientific breakthrough, while others worry about ethical and ecological ramifications. Public support (combined with government and scientific support) will play a crucial role in the future of these projects.

Sources: (BBC) (Colossal Laboratories & Biosciences) (TheCollector) (Scientific American) (Popular Science) (Labiotech.eu) (Smithsonian Magazine)

See also: Animals that came back from the brink of extinction

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