5 Extinct Animals Scientists Are Bringing Back Before 2035

[00:00:00]What if five extinct animals could be walking the earth again before 2035?

[00:00:05]Right now, scientists are using ancient DNA, gene editing, and living animals to rebuild creatures that disappeared thousands of years ago. But bringing them back is not as simple as cloning a fossil. Some experiments could [music] endanger living species, while others might create animals that only look like the originals. From an ice age tank to a bird taller than a person, these are five extinct animals. scientists could bring back before 2035 and the final animal may already be returning. Number five, direwolf. What does it really mean to bring back a dire wolf? In 2025, a company called Colossal Biosciences showed the world three large pale animals. Scientists created them by changing the DNA of greywolf cells. The company called them direwolves. The animals are real and the DNA changes are real. But are they truly dire wolves?

[00:00:59]Ancient DNA shows that dire wolves were not just bigger greywolves. They came from a different family line. Direwolves and modern wolf-like animals separated about 5.7 million years ago. Direwolf fossils show that they had wide skulls, strong jaws, and powerful bodies. These features helped them hunt large ice age animals. Scientists compared direwolf remains with greywolf DNA. They then made 20 changes in 14 genes. These genes affected the animals size, skull shape, muscles, and fur. The edited cells were placed inside dog egg cells. The embryos grew inside female dogs, which acted as surrogate mothers. The puppies were born and survived. Supporters say this counts as bringing back an extinct animal. The new animals have some direwolf features and might be able to do a similar job in nature. Critics disagree. They point out that almost all of the animals DNA still comes from greywolves. Scientists did not clone a complete direwolf [music] cell or use a full direwolf genome. Some fur changes were also taken from modern animals because they were safer. This creates a bigger question. What makes an animal part of a species? Is it the way it looks, its DNA, its behavior, or the job it does in nature? To create a more accurate dire wolf, scientists would need much more ancient DNA and many more gene changes. They would also need to prove [music] that the animals grew and behaved like real dire wolves.

[00:02:28]Scientists may create more direwolf-like animals before 2035. But creating a true direwolf, also called anosion dyrus, is much less likely. The next animal on our list makes the direwolf project seem simple. Scientists are not trying to grow a mammal inside a familiar surrogate mother. They are trying to hatch a bird taller than a person using relatives small enough to hold in your arms. Number four, giant moa. How could scientists hatch a bird that could lift its head more than 3.5 m above the ground? The giant moa's closest living relatives are small birds from South America called tinnamus. The huge difference in size creates a major problem. New Zealand was once home to nine kinds of emoa. Some were about the size of a turkey. Others, like the South Island giant moa, were much larger. The biggest females stood about 2 m tall at the back. When they stretched their necks, they could reach leaves about 3.6 m above the ground. Moas ate plants.

[00:03:30]They were not dangerous monsters like the creatures shown in movies. Still, their long legs and huge bodies would have made them look prehistoric. After humans arrived in New Zealand, they hunted moas and burned parts of their habitat. Within a few hundred years, all moa species were extinct. Scientists have found moa bones, eggshells, feathers, skin, dried body tissue, and even preserved [music] droppings.

[00:03:55]Ancient DNA from these remains has helped researchers learn how moas were related to other birds. In 2025, Colossal Biosciences announced a project to recreate the South Island giant moa.

[00:04:07]The company is working with the Uni Tahu Research Center. [music] Scientists probably cannot clone a moa in the same way they might clone a mammal. A bird egg cannot easily be rebuilt and placed inside a surrogate mother. Instead, researchers may edit special reproductive cells from a living bird.

[00:04:25]They could place those cells inside a host bird. Later, the host's descendants might carry moalike traits. But which bird should be the host? Tinamus are closely related to moas. Emis are much larger and may be easier to work with.

[00:04:39]However, neither bird lays an egg as large as a moa egg. Because of this problem, scientists are also studying artificial eggshells with living chicks.

[00:04:48]These experiments are important progress, but they have not produced [music] a moa embryo. Scientists might create a moaike bird before 2035.

[00:04:58]However, many serious problems remain.

[00:05:00]Moas are genetically different from living birds and recreating their giant bodies would be difficult. Scientists must also think about animal safety and well-being. Mori groups must have an important role in deciding whether moas should ever return to New Zealand and if creating a giant bird is difficult. The next animal raises an even harder question. Should endangered living rhinos be put at risk to recreate an ice age tank? Number three, woolly rhinoceros. What would happen if [music] scientists could rebuild the DNA of a woolly rhinoceros? But bringing one back could put living rhinos in danger. That is what makes this ice age animal so difficult to study. The woolly rhinoceros was built for cold weather.

[00:05:43][music] It had thick fur, a strong body, a large shoulder hump, and two horns.

[00:05:48]Its long front horn pointed forward. An adult could weigh about two tons. Woolly rhinos lived on wide grassy lands called the mammoth step. They used their horns and strong [music] necks to push snow away and find plants underneath. Near the end of the ice age, the climate became warmer. [music] The open grasslands began to disappear.

[00:06:07]The woolly rhinoceros became extinct about 14,000 years ago. Frozen ground has preserved [music] woolly rhino bodies with hair, skin, and other tissue. Scientists have collected proteins and highquality DNA from these remains. One amazing woolly rhino genome came from tissue found inside a frozen wolf pup. The DNA showed that some of the last woolly rhinos were still genetically [music] healthy. This suggests that the species may have disappeared quickly because its environment changed, not because its population [music] slowly became weak or unhealthy.

[00:06:41]However, having a genome is not the same as having a living animal. To clone a woolly rhino, scientists [music] would need a complete undamaged cell nucleus.

[00:06:50]None has been found. Another option would be to edit cells from a living rhinoceros. [music] Scientists might use the Sumatran rhino because it is closely related to the woolly rhino, but [music] this plan creates serious problems.

[00:07:03]Rhino eggs are hard to collect and rhino pregnancies last a long time. Any egg donor or surrogate mother would come from a species that is already endangered. So far, no confirmed woolly rhino project has created an embryo.

[00:07:17]Scientists might create a woolly rhino-like animal before 2035, but it would be very difficult. For now, studying more ancient DNA is much more likely. The next animal has the opposite problem. Scientists may be able to read more of its DNA, but bringing back a giant predator would be much harder to control. Number two, cave lion. Why does a frozen cave lion cub make bringing the species back seem possible? Even though it tells us very little about how an adult cave lion would behave. Frozen bodies can preserve an animals body and DNA, but they cannot preserve the knowledge and behavior passed down by its family and group. Cave lions once lived across Europe, Asia, and Bingia.

[00:07:59]They were related to modern [music] lions, but they belonged to a separate group. They had long legs and powerful bodies. Ice Age art shows that they may have had small manes or no large manes at all. Some cave lions were larger than many lions living today. Their bones are often found in caves, but cave lions did not live only inside them. Caves simply helped preserve their remains and signs of their meetings with humans.

[00:08:23]Paintings, carvings, and small statues show that ancient people watched cave lions closely and probably feared them.

[00:08:30]Some of the strongest evidence came from the frozen ground of Siberia. [music] Several cave lion cubs were found with their fur, whiskers, and paws still preserved. Scientists [music] have also studied cave lion DNA. They discovered that cave lions separated from modern lions a very long time ago during the pleaene period. Because of this, a modern lion would be the most likely starting point for creating a cave lion-like animal. In theory, scientists could edit lion cells, create embryos using cloning methods, and place them inside a lioness. However, there is no confirmed project creating cave lion embryos. Ancient [music] DNA is broken into small pieces and thousands of genetic differences still exist. An animal's growth also depends on more than its DNA sequence. There is another serious problem. A young predator learns how to behave from its mother and social group. A cave lion-like animal born in a laboratory might look like a cave lion, but it might behave differently from every real cave lion that ever lived.

[00:09:30]Before 2035, scientists are more likely to create cells with a few cave lion traits than a full breeding group. These animals would need huge, secure reserves, plenty of prey, and permanent [music] care from humans. But the final predator raises the danger even more.

[00:09:46]Its most famous weapons were so extreme that scientists still debate how it used them without breaking them. Number one, saber-tooththed cat. How did Smileodon use its two huge teeth to bite struggling prey without breaking them?

[00:10:00]This mystery makes the saber-tooththed cat one of the strangest animals from prehistoric times. The name saber-tooththed cat describes several extinct groups, [music] but this countdown ends with smileon. Smileon had a short tail, very strong front legs, a deep chest, and a body built for grabbing prey instead of chasing it. Its long canine teeth extended [music] more than 15 cm past its gums. However, their flat shape made them easy to damage if pushed sideways. Smileon probably hid and waited for large animals. It then used [music] its powerful front legs to hold the prey down. After the struggle was under control, it opened its jaws very wide and carefully bit into a [music] soft part of the body. Its teeth were most useful only after the prey had stopped fighting. Thousands of Smileodon fossils have been found at the Labraa tar pits. These fossils show injuries, healed bones, and details about the animals body. However, scientists have much less genetic evidence. Researchers [music] have found some mitochondrial DNA from certain saber-tooththed cats.

[00:11:04]But Smileon separated from the ancestors of living cats millions of years ago.

[00:11:09]Scientists do not have a complete highquality smileon genome or a living cell that could be used for cloning. In the future, scientists might compare pieces of smileodon DNA with the DNA of modern cats. They could then add some smileon traits to cells from a living cat species. [music] However, no modern cat is closely related enough to be a perfect match. Collecting eggs and choosing a mother to carry the baby would also create animal welfare problems. Even if the birth worked, the animal would probably be a changed modern cat with a few smileon features.

[00:11:43][music] It would not be the original species and it would not have smileodon's learned behavior or ancient environment. So even though smileon may be the most exciting animal in this countdown, it may be the hardest one to bring back before [music] 2035. Bringing back a top predator would require a safe habitat, enough prey, and much more than public attention. [music] The final question is not whether humans can copy saber teeth. It is whether we are truly bringing back an extinct species or creating modern animals that only carry some features of the dead.

[00:12:15]So, which extinct animal should scientists bring back first? And should they bring any of them back at all? Let me know in the comments and subscribe for more science stories like