Can dinosaurs be resurrected? This ancient reptile was once the overlord of The Earth, ruling for more than 100 million years, far longer than humans, but about 65 million years ago, for unknown reasons (possibly asteroid impact), the vast majority of dinosaurs mysteriously disappeared, and a small number of those who survived may have evolved into birds.
Dinosaurs were once the overlords of the earth
However, the research team of the Chinese Academy of Sciences recently extracted some chondrocytes from the fossil of a tail feather dragon, which even has filamentous chromatin, and DNA is an important part of the cell chromatin, so it initially shows the possibility of dinosaur cell DNA! If we could really extract the DNA of the dinosaurs, would we be able to resurrect this extinct creature?
Asteroid impacts may have been responsible for the extinction of the dinosaurs
For a long time, out of curiosity and yearning for these ancient beasts, people have always had the desire to resurrect dinosaurs. For example, the movie "Jurassic Park" imagines a story of scientists resurrecting dinosaurs, the specific method is to extract the dinosaur blood from the mosquitoes in prehistoric amber, obtain the DNA fragments of dinosaurs from it, and then use the DNA of frogs to fill the gaps in these fragments to form a complete dinosaur DNA, and then use DNA to clone and breed dinosaurs on a small island. But then the situation spiraled out of control, and the island became a battlefield for dinosaurs to kill humans.
Although the plot of the science fiction story is fictional, it has a certain rationality, and even some research teams have really tried to use this method to find dinosaur DNA in ancient amber. Let's press the table first. Here we need to introduce whether DNA can be preserved for 125 million years.
Insects in amber
Dna, whose scientific name is DNA, is an organic macromolecule consisting of two double helixed strands of nucleotides and the bases on them, in which the genetic information of the organism is preserved. During the life of the organism, these DNA molecules are constantly copied, and there is a repair mechanism, and the genetic information is preserved and passed on to the next generation. However, once an organism dies, degradation occurs because the DNA molecule is not stable.
Degradation is the breaking of DNA strands, under the action of bacteria, as well as high temperature, acidity, alkali, radiation environment, DNA will quickly degrade, breaking into relatively small fragments. For example, when forensics do identification, if the time is long and the storage environment is not good, it is difficult to extract complete or long enough DNA. In order to preserve DNA for a long time, a low-temperature, dry, breathable environment is required, such as direct -80 °C freezing. But in nature, it is difficult to have such conditions.
DNA molecules degrade
Take dinosaurs, for example, living 100 or 200 million years ago. After this long period of time, most dinosaurs have not even left the slag, and a very small part has been transformed into fossils under very accidental conditions, but the biological tissue in the fossil has basically been mineralized, and even the cellular structure cannot be seen, let alone found DNA. And nature is full of organisms, fossils are easily contaminated by the DNA of other organisms, and the DNA extracted from fossils basically comes from other organisms, not dinosaurs.
Dinosaur skeleton fossils
So is it feasible to find DNA from ancient amber, as stated in Jurassic Park? The answer is not reliable! Although amber can retain the remains of many ancient insects, it seems to be alive, but because its formation process to go through high temperature and pressure, enough to destroy the fragile DNA, so it is futile to obtain genetic information of dinosaurs in this way, the previously mentioned researchers who tried to use this method to find dinosaur DNA, and later all failed. Some claimed to have found dna from ancient insects, which later proved to be the result of contamination by other organisms.
So why can China find suspected DNA of dinosaurs 125 million years ago in fossils this time? It turned out to be related to the special formation environment of this fossil. Researchers at the Chinese Academy of Sciences extracted these chondrostocytes from a fossil of a dragon with tail feathers unearthed in Liaoning. Apatosaurus was a bird-like dinosaur with long tail feathers, but it did not fly, standing up as tall as a knee, belonging to the oviraptorosaurs, living in a lakeside environment in the Early Cretaceous.
The tail-winged dragon has feathers on its body, but it cannot fly
The western part of China's Liaoning Province has unearthed many fossils of dinosaurs and other animals, known as the "Rehe Biota", and this tail-winged dragon is also from western Liaoning. During the Jurassic-Cretaceous period, there were many freshwater lakes in the western Liaoning region, and the environment was quite good, and a large number of animals and plants flourished here, including dinosaurs. But at the same time, the earth's crust here is very active, volcanic eruptions are very frequent, and a large number of animals suffocate or poison to death during volcanic eruptions, and then are quickly buried by volcanic ash, forming fossils.
This burial environment is very special, mineral-rich fine-grained volcanic ash can protect the internal tissue structure of ancient organisms, and even some cellular structures have been preserved, especially the dinosaur chondrocytes, which underwent a silicification process, and silica replaced the original organic tissue, while also retaining the original microstructure.
The tail feathered dragon died during the eruption and was buried by volcanic ash
Researchers at the Chinese Academy of Sciences took a sample of cartilage from the right thigh bone of the tail feather dragon, deminerated it, and then stained it with a substance called hematoxylin, which would appear purple when combined with the nucleus. As a result, one of the dinosaur chondrocytes was dyed in exactly the same form as the chicken chondrocytes, it turned purple, and the nucleus and the filamentous chromatin in it could be seen, indicating that it was not completely petrified. Since DNA is found in chromatin, it's likely that dinosaur DNA, even some remnants, will be found here.
Nucleus and chromatin in dinosaur fossil chondrocytes
But even if DNA can be found in 125 million years ago chondrocytes, it is impossible to be complete, and if you are lucky, you may be able to find some fragments, and you need to use gene editing techniques similar to "Jurassic Park" to make up for the missing parts to repair the completed DNA, which is a difficult task. If we can do this in the future, maybe we can really clone the living bodies of dinosaurs and make these earth overlords who have disappeared for tens of millions of years reappear on earth, how exciting it will be!
However, there is a big problem with this: if we do resurrect dinosaurs, where will they end up? The earth is very different from 65 million years ago, the environment has changed dramatically, the overlords of the past have been unable to adapt, if they are released into nature, they are likely to starve to death due to lack of suitable food, even if they fight, they may not be able to do highly evolved modern mammals.
Dinosaurs have become unsuitable for modern environments
Some people are worried that there will be the kind of carnivorous dinosaurs in the movie hunting and killing humans, in fact, that is just the need of the plot, there are really carnivorous dinosaurs escaping into the human community, in the face of modern weapons and equipment, being shot is also a matter of minutes. As a result, resurrected dinosaurs were either used for research or exhibited at zoos, selling tickets to viewers and living the life of a prisoner for a lifetime. If so, what is the point of reviving them?