Mammoths are an extinct group of mammals whose fossils are found in Asia, Europe, and the Americas. As the drawing above shows, they probably looked a lot like elephants, but they had significantly more hair and long, curved tusks. Scientists have learned a lot about these animals, since they left behind plenty of well-preserved remains. Some have even been found frozen, with skin, internal organs, and even DNA preserved. Well, a find out of the New Siberian Islands might have just surpassed all other finds when it comes to preservation.
Russian scientist and head of Northeast Federal University Mammoth Museum, Semyon Grigoryev, led an expedition that was specifically looking for well-preserved mammoth remains that could possibly be used to bring mammoths back from extinction. Since parts of the permafrost in Siberia have been thawing in recent years, they believed that frozen mammoth remains might be in the process of being exposed for the first time. They thought that if they could find such remains, some of them might be well-preserved enough to contain the materials necessary for cloning, which might end up producing living mammoths!
Recent reports indicate that the team might have, indeed, made just such a find. According to news reports, the researchers found a mammoth whose lower body was encased in ice. Not frozen soil – actual ice. This resulted in remarkable preservation for that portion of the body. The team says that the muscles are pristine, and they have the red color you would expect from muscle tissue. Even more impressive, they say they have found what appears to be blood in the remains! The article linked above has a picture of tube that contains some of the liquid that the team thinks is mammoth blood. If the researchers can find living cells in the blood or any other part of the remains, they will be given to the Sooam Biotech Research Foundation for cloning in the hopes of producing live mammoths.
While this is all very exciting, I do have to add a few words of caution.
First, it’s not at all clear that the liquid found in the remains is really blood. It looks like blood, but as my mother once told me, looks aren’t everything. I think she was referring to something else (see my picture), but her sentiment applies here as well. Bacteria can produce thick, red liquid that looks remarkably like blood, so until the sample is chemically analyzed, it’s not clear what the red liquid actually is. Also, the fact that it is liquid is more than a little bothersome. At the time the discovery was made, the temperature was 7-10 degrees below zero (Celsius). That means the plasma in the blood should have been frozen. However, it wasn’t.
The researchers have an explanation for this: they think that like many animals living in very cold environments, mammoths had a natural “anti-freeze” in their blood that would keep it from freezing. While it is certainly true that some animals do have such “anti-freeze” in their blood, they are typically cold-blooded animals. I am not an expert in such things, but I don’t know of any mammal that makes a blood additive that keeps it from freezing when the blood’s temperature dips below 0 Celsius. Indeed, I can’t imagine how any mammal’s physiology would work if its blood reached such a temperature! Now mammoths did have a biochemical trick that allowed their blood to exchange oxygen efficiently at low temperatures, but this would not have prevented the blood from freezing.
However, suppose the red liquid the scientists found is actual mammoth blood. Does that mean they will be able to clone the mammoths? Not necessarily. In order for the cloning process to work, scientists need a living cell. So not only do the researchers have to find intact cells in their specimen, those cells have to be able to be revived so that they are completely functional. Only then can the researchers attempt the cloning process.
This leads us to the next problem. Let’s suppose there are intact cells that can be revived in the specimen. At that point, it is at least theoretically possible for the researchers to start the cloning process. This would involve manipulating the cell so that it reverts back to its undifferentiated (stem cell) state. At that point, the cell could act as a zygote (the cell that is made by fertilization) and start developing into an embryo. However, once the embryo reaches a certain state, it needs to be implanted in a living animal’s uterus to complete the developmental process. Where, exactly, will they find such a uterus? The scientists at the Sooam Biotech Research Foundation think that an elephant can be used. However, it’s not clear that’s possible. Typically, the uterus needs to be from the same species.
This leads us to yet another problem. The researchers will give any cells they find to the Sooam Biotech Research Foundation, which is headed by Woo-Suk Hwang. If you don’t recognize the name, he’s the scientist who published a paper in the peer-reviewed literature claiming to have extracted stem cells from the world’s first human clone. He also published a second paper claiming to have generated stem cells that genetically matched a specific patient. Both of those claims were shown to be made based on falsified data, and he was later convicted of fraud and embezzlement. I am not sure his foundation is really the one that should be handling such a project.
Now don’t get me wrong. I would love for researchers to be able to clone a mammoth. The scientific implications would be mind-blowing, and it would be incredibly cool to think that we could bring a species back from extinction. I am just very skeptical that such an accomplishment will come from this find.
Thanks for this explanation Dr. Jay. I heard this story on the news but am always curious to hear a good scientific analysis of a story like this. Fascinating!
I believe you are right on with your assessment here. The report of “blood” seems fairly sketchy to me since this is just popular press stuff so far. You are exactly right about the “anti-freeze”, that seemed just silly to me for the very reasons you gave. All in all, this story reminds me of the giant dinosaur egg discovery in Chechnya last year. The whole story made no sense but it was a public sensation in the press. In the near term (decade) I think it is highly unlikely that a mammoth can be brought back even if there intact cells as DNA fragmentation should still be a big problem and would prevent nuclear transfer cloning. But, I don’t think that the surrogate mother would pose as big of a problem. Mammoths are much more similar to Asian elephants than Asian elephants are to African elephants. Apparently African and Asian elephants might be able to produce hybrids (there is at least one that has been born though didn’t survive very long). Hence, an Asian elephant surrogate mother would likely be able to birth a mammoth. Of course there could be a few mutations that prevent this. I used to say that cloning extinct organisms would be impossible but I am now more cautious. Intact cells are probably not the way that clones will be produced but rather DNA synthesis of the chromosomes or some sort of sophisticated DNA repair of DNA from intact cells and then cloning. These technologies are out there but haven’t reached the level of sophistication necessary to make this type of closing possible yet.
Thanks for your comment, Joel. I didn’t know that mammoths were so close genetically to Asian elephants. That does temper my skepticism on the issue of a surrogate.
No way! It would be like jurrasic park!!! That would be epic, but wouldn’t it be scary? What if we don’t really know as much about cloning as we think? In my opinion the scientists should perserve the mammoth DNA and blood, then use it when we know what we’re doing.
Thanks for your comment, Nathanael. It probably would be a good idea to preserve some of the blood (if it’s blood) for after they have at least perfected cloning an elephant. I seriously doubt it is blood, however.