Not long ago, we just introduced the news that a foreign company wants to revive mammoths, which once again set off a hot discussion about the resurrection of prehistoric creatures.
(Photo caption: Mammoth)
With the development of human technology, the resurrection of prehistoric creatures has gradually become possible, making people more and more looking forward to seeing these long-extinct creatures. In particular, the most famous prehistoric creature dinosaurs fill people with curiosity. In particular, the movie "Jurassic Park" depicts scientists using genes extracted from dinosaur fossils preserved in amber to reconstruct a huge dinosaur kingdom in the modern world, which looks exciting and enjoyable. So, in real life, can we resurrect dinosaurs?
Unfortunately, this is not possible at this time. Because if you want to resurrect these prehistoric creatures, you first have to have their DNA. However, DNA is a substance that is difficult to preserve, and only a few million years is enough to destroy them, while dinosaurs have completely disappeared as late as 66 million years ago, so it is theoretically impossible to preserve complete DNA.
However, there is no shortage of "miracles" in this world. Recently, a team of scientists at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences (IVPP) and the Shandong Tianyu Museum of Nature (STM) successfully isolated the chondrocytes of a dinosaur, and even residual organic molecules and chromatin in its nucleus!
This dinosaur is a caudipteryx , an omnivorous dinosaur about the size of a peacock , with feathers on its forelimbs and tail , mainly distributed in Liaoning Province , and is one of the characteristic species of the Rehe biota in Liaoning. What's more, it lived 125 million years ago! This means that even over 100 million years, the DNA of prehistoric organisms may still be preserved through special pathways!
(Photo caption: Tail Feather Dragon)
Dr. Li Zhiheng, associate professor of IVPP and co-author of this study, has been studying the tail feather dragon for many years, and he introduced to us: The geological data accumulated over the years shows that the fossil preservation of the Rehe biota is very special, because the tiny volcanic ash buries the corpse and preserves it to the cellular level. ”
Even so, these cells cannot be very alive. After 125 million years, they have all undergone great changes. To better study these cells, paleontologists have to do some processing. They extracted a piece of distal joint cartilage from the right femur of the tail feather dragon specimen and decalcified it. Subsequent microscopic observations and chemical analysis showed that the cells were all silicified, which may be the key reason why they are so well preserved.
(Photo caption: Tail feather dragon that died from a volcanic eruption)
Not only that, but they also used chemicals to stain some of the cells. The stain they used was called hematoxylin, a substance that binds to the nucleus and stains it. Paleontologists have found that the cells of the tail feather dragon do have nuclei that appear purple, with some dark purple threads. This means that despite hundreds of millions of years, there are still some dinosaur nuclei that have been preserved, and even some primitive biomolecules and filamentary structures of chromatin remain inside!
Last year, we introduced Alida Bailleul, a postdoctoral fellow at the Institute of Paleovertebrates of the Chinese Academy of Sciences, and her colleagues suspected of having discovered dinosaur DNA. The fossil came from a dragon that lived more than 70 million years ago in Montana, and they found primitive proteins and chondrocytes in the fossils, and even organic macromolecules suspected of being DNA. However, at that time, this discovery was also controversial in the industry, and the results of the controversy have not yet been seen.
(Photo caption: Aguana dragon)
Bailleul, who was also involved in the study, said: "To be honest, we are obviously interested in the nucleus in fossils, because once there is DNA preserved, then most of it will be preserved here." ”
So, does this discovery mean that humans are about to be able to extract dinosaur DNA?
It's too early to say that. Admittedly, chromatin is similar to the well-known chromosome and contains genes in an organism. But for the question of whether the DNA in these cells can be extracted, IVPP paleontologists still can't guarantee a definitive answer, after all, the interval is too far, and the integrity of the DNA is very worrying. However, Chinese scientists did not say that this idea could not be realized, and Bailleul also said that at least it was still possible.
(Caption: Genetic Material DNA)
Extracting DNA is not yet finished, but the more important work is to sequence the genes, which is essential if you want to resurrect dinosaurs.
The oldest DNA sequencing ever performed by humans spans about 1.2 million years, and the remains of those prehistoric creatures were largely preserved in permafrost during the Ice Age. If chinese scientists can successfully sequence this time, it will increase this record by 100 times, which means that there are far more prehistoric organisms that humans may achieve gene sequencing than are now known, which is exciting to think.
In a paper published in the journal Communications Biology, the researchers point out that cartilage in prehistoric organisms is a seriously undervalued resource, and with the publication of this paper and the development of related technologies, perhaps people will realize how important they are in the future.
(Photo caption: Restoration of the tail feather dragon)
It should be noted that even if the complete dinosaur DNA is found and sequenced this time or one day in the future, it does not mean that the plot of Jurassic Park can come true, and cloning a dinosaur is still extremely difficult.
Even the legendary resurrection of mammoths a few days ago is not the use of cloning technology, but the use of gene editing technology, some mammoth DNA inserted into the Asian elephant DNA for breeding. To put it bluntly, this technique has bred nothing more than an Asian elephant that looks like a mammoth. Even to this extent, whether it can be achieved is still unknown, let alone resurrect the dinosaurs.
Even with close relatives like Asian elephants, whether mammoths can be resurrected is still unknown, not to mention that dinosaurs do not have such similar relatives in today's world. In addition, human cloning technology has not reached the level that many people imagine, which makes it more difficult to resurrect dinosaurs far beyond everyone's imagination.
(Photo caption: The dream of resurrecting dinosaurs is still far away)
In short, the resurrection of dinosaurs is still very far away from us, and the first problem to be solved is still complete DNA. Or maybe they should remain in the imagination and should not appear in today's world.