The recent discovery of a mammoth carcass in the Yukon gold mine in Canada has attracted a lot of attention because it is really special.
The large herbivore mammoth during the Ice Age, thought to have gone extinct 4,000 years ago, but because it lived during a special period of extreme cold and freezing, many carcasses have been preserved in permafrost to this day. In the Siberian permafrost of the Russian Arctic Circle, there are huge mammoth corpses frozen in ice, and locals once used to dig mammoths as a means of livelihood, and mammoth tusks are very popular in many places.
Mammoths unearthed are not uncommon, why is this one so special? Mainly because "it" is so well preserved.
The mammoth remains intact and the nail skin is clearly visible
Some miners suddenly found it while looking for gold in the permafrost. These people came from an Indigenous group that had lived along the Yukon River for thousands of years, named Trendek Hervechin, and the elders of the clan named the mammoth Nun cho ga, which means "big baby animal". Yes, this is a juvenile mammoth, and what makes it special is that it is so well preserved that although it has been dead for 30,000 years, the toenails, skin, hair, torso and intestines are complete and clear, as if they had just died in a few days.
Paleont Zazura said excitedly: "This is the most exciting scientific project I have ever been involved in, not one of them." ”
As a paleontologist who studies the Ice Age, mammoths are undoubtedly a central subject. But due to the age, we can often see only some of the harder teeth or bones today, and the rest of the parts are basically rotten.
In the history of ancient civilizations, the embalming and preservation of corpses was a worldwide behavior, such as mummies in ancient Egypt or tombs in ancient China. Usually the ancients would use dehydration and embalming or mercury embalming to keep the body as long as possible, but when we excavated thousands of years later, there were still almost only some residues left.
So when such a complete, perfect mammoth corpse is unearthed, many people have a question in their minds, can we use it to clone mammoths?
How hard it is to clone a mammoth
In fact, there are already a lot of countries doing this.
The British "Daily Mail" reported in 2008 that Russia wanted to use local advantages to clone mammoths within a decade and build a mammoth theme park, similar to Jurassic Park.
Russia does have a natural advantage in doing this kind of thing, as mentioned earlier, there are many mammoths preserved in the permafrost layer of Siberia, and from time to time some well-preserved individuals will be dug up, and the more complete the preservation, the more likely it is to successfully extract DNA for cloning.
But it has been 4 years since this incident, and there is no breakthrough, because although there are mature cases of cloning technology, it is too difficult to clone ancient creatures.
The cloned sheep "Dolly" that was once learned in textbooks is to extract a cell from the two ewes A and B, and then isolate the nucleus, and then inject the A sheep cell nucleus into the B sheep denuclearized egg cells, and after processing, the recombinant B sheep cells are cultivated into embryonic cells, and then put into the body of the C sheep to conceive, which can give birth to sheep exactly like A.
The first problem we have in this process is to obtain a complete mammoth cell and obtain genetic material, that is, DNA. Although we have fossils of mammoths, DNA degrades over time, and oxygen, sunlight, and water are severely damaged and cannot be cloned.
At present, the special environment of permafrost just provides good protection for DNA, so that they can be preserved for nearly 10,000 years, which gives our scientists hopes of successful cloning, but this is only the beginning, and there are still many problems to be solved.
When we finally found a well-preserved mammoth, and finally extracted a dna fragment from ten thousand years ago, then the new problem came again, we could not guarantee that it was "clean", it may be contaminated by foreign DNA from fungi, bacteria, plants, animals, etc., and because the mammoth is extinct, we can not have reference data, so we can not be sure that the DNA we get is normal, clean and pollution-free, even scientists may cause new pollution in the process of research. It is not possible to verify against the correct data.
Finally, there is a very important problem, that is, it is impossible to find a suitable "surrogate mother", that is, the C sheep that gave birth to Dolly.
Researchers can not find a living mammoth as a "C sheep", they can only start from the mammoth's close relatives, studies have shown that the Asian elephant and the mammoth blood relationship is closer, but this is only relatively speaking, the Asian elephant and the mammoth size difference is very large, even if the bred mammoth embryo, can be successfully transplanted into the Asian elephant and complete the final childbirth, there is still a long way to go.
Recently, a biotechnology company in the United States raised $60 million in research to revive mammoths. The ethical controversy of cloning technology has always been very large, and we will encounter many new problems in cloning ancient creatures, for example, mammoths have long disappeared from their previous food, and now they appear again, what do they eat, and how long can they live? Is it really worth it to resurrect 1 extinct creature at the cost of saving 8 endangered species? Throughout history, human beings have always polluted first, then treated, destroyed first and then saved.
It is hoped that scientists will also maintain communication with the public during the research process, and be as transparent as possible about some parameters and goals, and think twice.