The revival of mammoths is not necessary
It is better for Russia to become the homeland of elephants again
Alexander Berezin, Naked Science
Some environmentalists have long said that the revival of the mammoth would be beneficial to the northern regions of Russia. These animals, they say, could slow down global warming and recreate highly productive tundras. However, there is another point of view: there will simply be no place for tundra and tundrasteps in the next hundred years, and no mammoths will fix it. The ecosystems that will come to the north of Russia would rather use elephants – but quite different. We are talking about creatures twice as massive as tyrannosaurs. But are people ready for such new neighbors?
Mammoths are known to us almost better than any other ancient animal species. They are frequent characters in cartoons, dummies and stuffed animals of these animals are in many museums. And all because of their very high preservation in permafrost, which allowed researchers to accurately recreate their cute-furry appearance. It is a six–ton - like a modern African elephant – beast with twisted tusks, fur, small ears and anal fold (specific features that protect against frost and winds).
Russian ecologist Sergey Zimov, the creator of the "Pleistocene Park" in Yakutia, has been noting for decades that it would be nice to return mammoths to northern Eurasia in order to achieve greater diversity of fauna. Now to the north of the taiga to the Arctic Ocean stretches tundra covered with moss (lichen). The increase in its biomass is small, and unlike higher plants, the berry is practically devoid of proteins. Such vegetation cannot support an ecosystem with a large number of species: even reindeer switch to the yagelnik only when they have no other food.
Large mammals effectively destroy the yagelnik with their hooves. This allows grasses to germinate, which contain more proteins and trace elements. And herbs are also more actively using substances from the soil, and where they grow, the overall bio-productivity is much higher than where the tundra of the modern type lies. For example, Wrangel Island, where musk oxen (weighing up to 650 kilograms) were revived, is covered not with a berry, but mainly with herbs. This makes it somewhat similar to the tundra steppe that covered the main part of Eurasia during the last ice age.
Yagelnik in the taiga. Dense cover does not allow seeds of higher plants to get into the soil. The situation is similar in the tundra
With this, Zimov reinforces his considerations with the ideas that are fashionable today about combating global warming. He notes (and a number of scientists repeat it after him): the permafrost of the tundra and taiga have accumulated a huge amount of carbon-containing materials, the remains of ancient organisms. So far, they are frozen, that is, they remain torn out of the biological cycle. As soon as the permafrost melts, the bacteria decompose the dead organic matter, releasing billions of tons of carbon dioxide and methane into the atmosphere.
This, in turn, will spur global warming. And the warmer it gets on the planet, the less permafrost there will be, because it will begin to melt at ever higher latitudes. As for the consequences of soil thawing, Zimov is right: it is well known that only 2-3 million years ago broad-leaved forests grew on the Novosibirsk Islands, and permafrost in the northern hemisphere was quite rare.
The logic of Zimov is that mammoths will not allow the tundra to be replaced by taiga. And without the taiga, the surface of northern Eurasia will reflect more solar radiation into space. After all, steppe landscapes reflect much more solar radiation than the darker taiga. In addition, he believes that mammoths and other large herbivores will be able to break the snow cover in winter: tearing the snow, they will allow the northern frosts to freeze the soil better in winter.
Execution cannot be cloned
In modern science, it is often customary to report on unprecedented successes in the newest industries, but rarely talk about obvious failures. Therefore, many people have the impression that since scientists recreated Dolly the sheep a quarter of a century ago, it will be quite easy to clone a mammoth from samples found in permafrost these days. Other enthusiasts recall that for a decade and a half, scientists have been able to "print" DNA and then insert it into a living cell, from where its own DNA has been removed. Such an organism with fully synthetic DNA was first created in 2010 – and is called Mycoplasma laboratory (Mycoplasma laboratory).
The American startup Colossal, in collaboration with a major geneticist from Harvard, claims that it can do even easier. Since the DNA of the mammoth and the Asian elephant – from which the mammoths once originated - does not match by 0.4%, Colossal plans to simply make the missing inserts in the elephant DNA using CRISPR-Cas9 technology. The inserts will be copied from DNA fragments of "permafrost" mammoths, since almost all the genes have been preserved there.It sounds logical and even touching.
"Never before has humanity been able to use the full power of such technology to recreate the ecosystem, heal our Earth and preserve our future by restoring the number of extinct animals," he says Ben Lamm, head of Colossal.
But he seems to be wrong. Even now, humanity cannot fully use, recreate and cure. (Even leaving aside how much the recreation of an arbitrarily selected species from the past can be assessed as a "cure").
The fact is that cloning and editing DNA in real life is not very similar to a bright picture from the popular science press.
Cloning in this sense is a technology of limited utility. It's not that Dolly the sheep died a little earlier than expected: the fact is that cloned creatures generally have noticeable problems with viability. Sexual reproduction – as opposed to asexual – appeared because it is more effective than asexual. And it's not just that the worst males and females reproduce less often, but also that fertilization during sexual reproduction literally "corrects the mistakes of nature."
During meiosis (division of the eukaryotic cell nucleus) there is a process of cutting DNA into parts, followed by its "repair". Organisms that normally reproduce sexually will accumulate more errors in DNA when switching to cloning. As a result, during cloning, the probability of pregnancy loss by a "surrogate mother" is higher, and the overall probability of fetal loss is higher. What does this lead to? While trying to restore by cloning a recently extinct species of mountain goat in Spain, the prototype died shortly after giving birth due to a congenital lung defect.
But with a mammoth cloning is unlikely to even begin. Human frozen cells normally lose their viability after a few decades. Mammoths became extinct 3700 years ago (then the last died on Wrangel Island), just a thousand years after the era of the pyramids. It is doubtful that the cells of complex creatures can be suitable for cloning after lying in the ground for thousands of years.
Maybe their DNA synthesis will help out? Not either. After the death of an animal, its DNA breaks down into many fragments after some time. There are about three billion "elements" in each mammalian DNA (both ours and mammoths), and if it were pulled into one chain, its length would be a couple of meters. What happens if you need to restore the exact sequence of a chain of three billion links, but before that the chain was torn into small pieces?
Love Dahlen of the Swedish Museum of Natural History notes:
"All the results of studying mammoth DNA show that they have crumbled into tens of millions of fragments. And there is no way to put them back together [in the right order]."
How did biologists create the same Mycoplasma laboratory, an organism with fully synthetic DNA? It's very simple: they built components of synthetic DNA printed with a special device, focusing on the available samples of "live" DNA of ordinary, "non-laboratory" mycoplasma. But no one on the planet has the whole mammoth DNA – and never will.
It is almost impossible to collect such DNA in the correct order by chance. Imagine that you have a puzzle of three billion pieces, and even three-dimensional. Moreover, even a single mistake during its assembly can lead to the death of the "collected" creature. The probability of success is purely theoretical.
So the Colossal company, like its predecessors, is either dreamers or those who are trying to "cut down the hype". The path they propose is most likely not suitable. This way you cannot restore a real mammoth. Even if we limit ourselves to inserting mammoth genes into the genome of the modern Asian elephant, we do not know where exactly they need to be inserted so that the final DNA gives us an elephant with mammoth features – and not with congenital deformities due to incorrectly assembled DNA.
Love Dahlen continues: this path is "very difficult, if not impossible." First, not all fragments of mammoth DNA have yet been found. The current supposedly complete decoding is based on using the gene sequence of a modern elephant as a sample. "If mammoth-specific genes existed and they are important for the restoration of this species, it will not be possible to "resurrect" it [with DNA inserts]," the researcher warns. Let's be honest: it is extremely doubtful that there really were no such genes that mammoths had, but elephants don't have. Most likely, mammoth-specific genes did exist.
There is another problem: planting a "synthetic" embryo in the uterus of a modern elephant surrogate mother may end in miscarriage, because they are separated by millions of years of evolution, but such a risk cannot be estimated even with approximate accuracy.
Let's assume for a minute that Colossal is incredibly lucky, and the mammoth will still be restored. What will happen then – immediately a happy ending, or the beginning of endless problems?
Artificial mammoth in an artificial environment
The key question is: where should the reborn beast live? There are no tundrosteps in the modern world. The Ice Age tundra existed because the world of that time was different from the modern one. It was very cold on the planet, and water evaporates weakly from cold seas. Accordingly, there was very little rain. Therefore, in areas with serious insolation – such as modern Volgograd – there was very little precipitation, 150-300 millimeters per year. More importantly, there was only 180 parts per million of carbon dioxide in the air (and now it is 410). It is known from experiments that plants with C3 photosynthesis have problems with survival already at 150 parts of 2 per million. At 180, they still survive, but with great difficulty. It is this kind of C3 photosynthesis that trees use - that is why continental Eurasia of the Ice Age was practically treeless.
The sun's rays effectively warmed up the soil not protected by the forest in summer, contributing to the seasonal retreat of permafrost into the depths. Today, exactly the same effects are visible in the northern taiga after a fire thinning tall trees: when there is little shade of the crowns, the permafrost thaws strongly in summer, making up to a meter of soil or more accessible to the roots. Without fires in the northern taiga, plants have access to 5-30 centimeters of soil.
What will happen if we release a mammoth into the modern tundra? He will not be full of Yagelnik, this is quite obvious (there are almost no proteins there, and his bioproductivity by weight is small). Mammoths will have to be fed with herbs for many years. Then they will trample the yagelnik to the ground, and finally grass will begin to sprout. That's just in the north of Russia, after the destruction of the yagelnik, another type of plant likes to sprout: trees. Since the beginning of the XVIII century, the first forest appeared on Taimyr, and now the peninsula is being developed by larch in other places. It is known from the paleontological chronicle that only 4-9 thousand years ago there was practically no tundra within the borders of modern Russia, and the taiga went out to the Northern Ocean.
Why? Because forests inevitably benefit from grasses wherever the conditions of plant life are favorable enough. Grass can dominate trees only where it is so bad that trees cannot survive. For example, where there is too little water, or it is too cold. It was "so bad" and it was in the tundra of the past.
During the ice age, the "poor" air on CO2 forced the plants to open the stomata of the leaves more and lose more water. That is, they were all much more demanding of her. With 150-300 millimeters of precipitation in the tundra, it was difficult for even individual larches to survive – that's why grasses dominated. In the interglacial period, the tundra began to be replaced by forest, but then a new ice age brought it back.
But now the warming promises to be much stronger than in the past interglacial periods. The climate is likely to return to the Miocene – millions of years ago. In the Miocene, there was no tundra steppe, and there were no mammoths either: the planet was warm, there was a lot of CO2 in the air, plants required less water and received more heat. Naturally, in such conditions, the tundra will be replaced by a forest, and not turn into a grass tundra.
What will a mammoth eat in the forest? It should be recalled here that large herbivores are not big fans of coniferous trees. They have quite specific leaves (needles), a lot of resins in the composition, and so on. Elephants can eat small coniferous trees (this happens in zoos), but they still won't become their main food.
Senior Researcher at the Mammalian Laboratory of the Borisyak Paleontological Institute of the Russian Academy of Sciences Yevgeny Mashchenko emphasizes: "In the modern taiga, large mammals also do not live everywhere. Moose and deer prefer the edges, where there is an undergrowth of deciduous plants – alder, willow. They mostly feed on them."
What will a mammoth eat, even if the northern taiga is not too generous to modern large mammals? The grass will be effectively silenced by larches that have already begun the re-conquest of the tundra, which they owned several thousand years ago. But mammoths will not be fed with larches. Not a single large mammal feeds on them in noticeable volumes.
Of course, people can fix things. Larches can be cut down – manually – this will allow the herbs to grow in conditions trampled by mammoths of the yagelnik. But then this is not wildlife, but a carefully cultivated nature reserve.
Recall: from the observation of elephants, it is known that they roam very long distances and do not live in one place for a long time. This means that mammoths will not be able to trample the growing larches with their feet. That is, without human intervention, the tundra steppe will simply become a taiga – as it was already 4-9 thousand years ago. What kind of return of ecosystems of the past can we talk about if mammoth landscapes with modern "rich" CO2 air will not only have to be returned, but also maintained manually?
That is why Yevgeny Mashchenko, when asked "would [Zimov's] Pleistocene Park suit a mammoth", concludes:
"No, there is nowhere for the mammoth to return. There are no ecosystems in which the mammoth existed. Some elements of such ecosystems exist in central Yakutia, Alaska and in some parts of Arctic Canada. That is, it will be an animal that will need to be fed, watered."
Such a project has nothing to do with "recreating the ecosystem, healing our Land and preserving our future by restoring the number of extinct animals." It has to do only with "recreational" agriculture: the revival of a species only for it to live as a tourist attraction. By itself, the mammoth in the climate of 2100 will not be viable almost anywhere.
You can drive him to a small island, like Wrangel Island. There is nowhere to migrate there, and by trampling the mammoths will not let the forests recapture the island. But the trouble is that this will not be a natural habitat for them either. It is known that once on Wrangel Island last time, mammoths turned into dwarfs (no more than two meters tall), and the area of the island led to a small population and forced closely related crossing and degeneration.
Stop, we have a replacement: an elephant instead of a mammoth!
We emphasize: the reintroduction of elephants in our country may very well make sense. Large herbivores in the ecosystem play a huge role, which no one really thinks about: they maintain the soil in a normal state.
Phosphorus and a number of other trace elements do not come to the surface with rocks everywhere. Where there are exits of phosphorus–containing rocks, water carries them as far as it can, but - maybe not everywhere. To carry phosphorus to other places, large animals are needed. They eat plants in phosphorus-surplus places, then go the other way and enrich the soil of phosphorus-deficient places with their feces. Elephants in Africa are one of the most important natural "phosphorus recirculators". Due to particularly long-distance migrations, they are more successful than other animals in distributing phosphorus where it is needed.
What happens in ecosystems where there are no large herbivores for a long time is clearly seen in the example of Australia. Before the arrival of humans there, large local herbivores distributed phosphorus normally. Later they were exterminated, and phosphorus was not distributed with the required intensity for tens of thousands of years. As a result, local soils are the poorest in phosphorus in the world. Australian farmers cannot get a normal harvest without phosphorus fertilizers, and among the "pristine local flora" those species that were not dominant at all before the arrival of man dominate – but they tolerate acute phosphorus deficiency better than others.
Previously, the north of Eurasia had a lot of large herbivores, which now do not exist. Without them, local forests will sooner or later face the Australian scenario of acute phosphorus deficiency. And large herbivores would be very useful to them!
We can't revive the mammoths – it's a pity, of course. But there is an alternative that allows you to solve the "phosphorus problem": an Asian or even an African elephant. It is definitely colder in Russia than in the homeland of these animals. But the fact is that large mammals generally tolerate cold more easily than heat.
From the experience of keeping elephants and lions in zoos with open areas, it is known that with gradual adaptation to the cold, they themselves can go out into cold and frosty air. Of course, they do not have mammoth wool, but it is not so necessary today: the ice Age tundra was an exceptionally windy and dusty place. Today, winds of similar strength regularly occur in Siberia, except on the ocean coast.
Nothing prevents us from trying to gradually acclimatize Asian and/or African elephants, first in large fenced reserves in southern Russia, and then, as they get used to it, move everything north, at least to the southern taiga zone. Who knows, maybe in time – and to the north?
Elephants play the role of major ecosystem engineers not only by spreading phosphorus and other useful trace elements. They also dig the soil to get to the underground water – and then such "wells" are visited by other large herbivores. Przewalski's horses from the Pleistocene Park also love water, but they often can't get to it themselves. The same applies to bison and bison. Certainly, the introduction of an elephant in Russia would lead to an increase in its biodiversity.
Moreover, the straight–tusked forest elephant (Palaeoloxodon antiquus) has already lived here - many hundreds of thousands of years. A species close to it (sometimes it is considered a subspecies of its European counterpart), Asian Palaeoloxodon namadicus reached a mass of 22 tons. Both of them flourished quite well: it was these types of straight-tusked elephants that reached a height of more than five meters and a mass of 15-22 tons. Today paleontologists do not know of a larger land mammal than the erstwhile straight-tusked elephant, once typical of the Russian Plain. It was 2-3 times more massive than the largest modern elephants or tyrannosaurs of the past.
A straight-tusked forest elephant in the artist's view. In practice, these creatures were larger than it seems in the picture: up to five meters and weighing twice or three times more than the largest elephants of our time
The reasons for the former prosperity of the straight-tailed forest elephant are clear: he is not a mammoth. Palaeoloxodon antiquus it was clearly adapted to eating tree branches and their bark and did not have a mandatory binding to the grass. During the interglacial period, broad-leaved forests spread very widely across Eurasia, giving abundant food to the forest elephants of the north. And the climate of the end of our century, without any global projects, is likely to be a Miocene climate, three or more degrees warmer than the current one (most climatologists agree on this).
It is known from the paleontological chronicle that at such temperatures broad-leaved forests dominate even on Novaya Zemlya. A mammoth without a restructuring of biology would hardly live in them, but such an ecosystem is a native home for a straight–tusked forest elephant. For him, you do not have to manually "change the landscape": an ordinary elephant is already well adapted to living in forests and woodlands.
But there is a problem here, and a serious one. At the age of 10 to 20 years, male elephants fall into a state of "musta" ("must" – from "drunk" in Farsi). During this period, a month long, male elephant testosterone rises to 140 times the norm, and they roar. Pregnant female elephants immediately respond and run to this roar. And all the other elephants, and other animals, run away in all directions to the best of their strength – an elephant in a must state easily attacks anyone, kills and mutilates rhinos, male elephants and even females who do not want to mate. Most of the murders of people by elephants – and there are far more of them than the number of murders of people by wolves or white sharks – falls on the must.
A small African elephant in a state of must attacks a giraffe, he tries to hide
It should be understood that the relocation of elephants to Russia is unlikely to change their habits much. And who wants to live next to a creature prone to periodic madness with the mass of a small diplodocus?
Of course, you can also fight must by putting old males in groups, which somehow (in a not very clear way) suppress the "musty" behavior of young male elephants, keeping them within the bounds of decency. But in the wild, you can't feed on every herd of old males.
All this means that the reintroduction of an elephant (if we suddenly get together) to modern high latitudes will require great caution and great enthusiasm on the part of the local population. Do we have enough of both?
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