Science fiction books write about bringing prehistoric animals back to life. But how could we do this? Is it ethical? We might be closer than you think.
Humans are fascinated by prehistoric animals of gigantic dimensions and imposing appearance. This fascination has led to several science fiction books like Jurassic Park, depicting the resurrection of dinosaurs and other prehistoric creatures. Now two groups of scientists from Harvard and the Sooam Biotech lab of South Korea, race to bring extinct ice age creatures back to life using advanced genetic technologies. However, all technical details about the progress of these unbelievable plans are not released. Why? Is there really a plan to create an ice age park? Is it possible to do it? Recently developed genetic engineering techniques such as CRISPR and modern cloning technologies of big mammals could actually make possible the “De-extinction” of prehistoric animals.
A dream difficult to achieve
Michael Crichton’s bestseller Jurassic Park described a situation where humans were able to bring dinosaurs back to live. To achieve this challenging goal, they presumably reconstructed the genome (complete DNA code) of extinct dinosaur species based on blood samples present in mosquitos trapped in amber. Today we know that the possibility of finding enough intact DNA for elucidating a dinosaur’s genome is rather remote. This is because after certain time DNA strands break up and irreversibly degrade. To the date the oldest genome ever reconstructed, belongs to a 700.000 years old horse spice from the Pleistocene era. The study was carried out by the Natural History Museum of Denmark among others. Due to the scarce amount of prehistoric DNA needed to sequence an entire genome or clone an animal force scientists to consider other alternatives.
Creating dinosaurs by reverting bird evolution
Decades of analysis of the dinosaurs’ anatomy and comparative zoology have provided good insights into key evolutionary events that turned the body of these gigantic reptiles into what today are modern birds. This knowledge combined with complex genetic engineering tools make possible amazing experiments that recall those of Jurassic Park scenarios. In 2015, a group researchers from of Brazil and Chile made an awesome breakthrough by switching off a gene that controls among other things, the development of the fibula bone (leg) in chickens. In birds, this bone does not connect to the ankle, while in dinosaurs it does. This particular anatomic configuration prevented dinosaurs from having the opposable toe found in modern birds. You can see this in the picture below from the original publication.
The outcome of this genetic modification surprised the scientific community as the chicken embryo grew dinosaur-like legs as you can observe in the video below. The press quickly coined the term “reverse evolution” referring to the idea of tweaking genes to revert modern evolutionary traits to the prehistoric version. Although this achievement is quite remarkable, it is only one example of small steps that might pave the way for the reconstruction of the prehistoric fauna.
Ice age animals are frozen in time
Unlike dinosaurs, the remaining of other more recent prehistoric animals, for example, those from the ice age, are better preserved. That is the case of wooly mammoths, Siberian dwellers during the Pleistocene period and thought to have gone extinct only 4000 years ago. These animals roamed the icy tundra feeding on grass until a combination of climate change and human activity threatened its existence. They eventually died out in the mainland around 10.000 years ago, but a small group survived in the little Wrangel Island until 4000 years ago. Recent findings of extraordinarily well-preserved mammoth carcasses have sparked intensive research to bring this animal back to life, a process so-called de-extinction. In 2015 a mammoth carcass was found frozen in Siberia in such a good condition that flesh was still fresh, and liquefied blood was also discovered. That was a good chance to obtain enough sample to sequence the complete genome, and perhaps intact cells with enough genetic material to attempt cloning. Just as wooly mammoths, other extinct ice age animals such as cave lions, wooly rhinos or bison may very well be found in conditions good enough to extract intact DNA.
The science behind and Ice Age Park
With the abovementioned findings, a race set out to bring prehistoric animals back to life with arguably useful purposes. Two teams from the USA and South Korea are seriously working on bringing back the wooly mammoth. Both teams attempt this science revolution by two completely different methods. But how are they going to do that?
The first team led by Dr. George Church, professor of Genetics at Harvard Medical School, is using a revolutionary genetic engineering tool called CRISPR/Cas9. This is a new technique by which we can very accurately introduce genetic mutations in a very specific and rapid manner compared with the traditional methods. With this technique, scientists might be able to introduce the characteristic genetic traits of wooly mammoths into the modern Asian elephant genome (their closest living relatives). For example, genetic traits like long hair, subcutaneous fat or a freezing resistance hemoglobin. In fact, the wooly mammoth and the modern Asian elephants are genetically very similar. Dr. Vincent Lynch and his team, have engineered mice with mammoth heat-sensing gene versions and observed that they react less to heat than normal mice. This means that they could tolerate better cold temperatures than unmodified mice. If scientists manage to introduce all necessary mutations in the elephant genome, they could potentially use a surrogate elephant mother to grow an engineered mammoth-like elephant on her.
Much of the progress of this technical work is not published in scientific journals, conferences or media. But one can imagine the incomes of having exclusivity over the display of a wooly mammoth alive, which also raises ethical concerns. Could some of these labs be working in the shadow to achieve something bigger than CRISPR/Cas9 experiments on elephant cells? What is more, who are the main sponsors of this research? You can read more details about this exciting research plans in the link below.
The second team, and not the least controversial, is a South Koran lab called Sooam Biotech Foundation. These researchers are pioneers of the cloning technology, largely attributed to the Korean scientist Hwang Woo-suk. He was prosecuted for ethical violations on research carried out with human eggs allegedly from non-transparent sources. Sooam biotech is probably most known for its capacity to clone dogs for about 100.000$ (see link below).
As a matter of fact, this institution openly talked about their plans to clone the wooly mammoth using their expertise. For that, they teamed up with a Russian university to hunt fresh mammoth carcasses in Siberia hoping to find one from which they can extract an intact cell nucleus and transfer it to an Asian elephant egg. This process is called cloning, and like Dolly the sheep, an exact copy of the mammoth should be expected. Obviously, this process presents numerous challenges, beginning with a poorly developed reproductive technology for elephants or the ethical concerns of using endangered species for cloning purposes. But what if they manage?
The purpose and place of the Ice Age Park
Why would we want to bring extinct species back to life? If they went extinct it is probably because they could not cope with the environmental or human pressure. By bringing these animals back to a dramatically different world from the one they were adapted to. Aren’t we just going to make them suffer as many other modern species? Is it really justified to use endangered species such as Asian elephants for reproductive purposes whose benefit is not really well proven? These are some of the concerns we need to address before any attempt of creating an ice age park. But scientists have their arguments to go on.
Dr. George Church believes in a theory published by the Russian scientist Dr. Sergey Zimov. He believes that prehistoric animals played a major role in maintaining the permafrost cold (soil layers frozen for a long time). Without these animals wandering around and stepping on snow, the permafrost layer warms up every year and releases greenhouse gasses trapped in it. This phenomenon is due to the heat-insulating capacity of snow. Sergey Zymov has moved to a remote corner of Siberia and created the Pleistocene park. There, he is reintroducing animals such as bison or Siberian horses to prove his theory. He believes that the introduction of ice age fauna would help the maintenance of the permafrost layer and therefore reduce greenhouse gas release. See video below:
Scientists pursuing the resurrection of the wooly mammoth support this argument to justify their research. But without further evidence of the positive impact that Pleistocene fauna would have on greenhouse gasses release, ethical concerns are that it is rather a lucrative research goal. The general public should be aware that research funding is scarce, and we have to choose funding projects whose objectives are clearly based on strong evidence.
Who knows if we will ever reach the dream of recreating environments with prehistoric living organisms. The technology is progressing at an unprecedented speed and giving us the opportunity to change our world. However, we have to be aware of the possible consequences of choosing certain paths. The purpose of science to help us understand how the universe works, make our lives easier, and our world better. The use of science to provide a leisure pool for humans at expenses of other animals’ life quality may not be the best purpose.
PhD in biotechnology
Denmark, August 2016