The return of extinct species to life is no longeris science fiction, even if the technology is not quite ready for it. For the most part, the hype on this topic was raised by the resumption of constant attempts to return woolly mammoths to the earth. And not only. Not so long ago, Harvard geneticist George Church said that his team will be able to present a hybrid embryo in two years. The Asian elephant will be genetically created, and some features of the mammoth will be transferred to this new species.
The idea is to return to our planet extinct according to our andnot only fault is far from new. The first attempt to regain the lost species, the wild mountain goat of Bucardo, was made in 2003, three years after the disappearance of this species. The cloned Bucardo embryo (Iberian Capricorn) was grown in the laboratory and then introduced into the belly of the goat to bear it. He managed to live only a few minutes due to a lung defect.
Attempts to revive the woolly mammoth - or its genetically modified version - were made even more often.
Japanese scientists tried to clone woollymammoth for over 15 years. They still have not been able to do this. Scientists like Church believe it is necessary to create a hybrid, not an ideal clone, using a gene editing method called CRISPR / Cas9.
- 1 The right tool for the job
- 2 Need the right genetic material
- 3 Resurrection and the price of conservation
- 4 The line of resurrection
The right tool for the job
CRISPR / Cas9 allows you to edit the genome of anyliving organism. He gained fame in 2012 and began to be touted as a possible cure for cancer and a number of genetic diseases, among other amazing uses. The basis of this technique was the mechanism for protecting bacteria from viruses.
Actually Gene Editing Toolallows scientists to rewrite the "history" of the genetic composition of the body. Its simplicity and accuracy in cutting and gluing genetic material makes it extremely versatile, allowing you to replace small pieces of DNA.
Since 2015, scientists led by Church have contributed45 "corrections" in the genome of an Asian elephant. For the most part, they were interested in the characteristics of the woolly mammoth - such as subcutaneous fat and long hair - which made them especially well adapted to the cold before they finally became extinct about 4000 years ago.
Need the right genetic material
It turned out that not every DNA of woolly mammothsSuitable for resurrecting the look. A study published this month in PLOS Genetics said that shortly before extinction, one of the last groups of woolly mammoths survived a “genetic crisis”, resulting in many unpleasant genetic mutations in its genome.
The study compared the genomethe mainland woolly mammoth, who lived 45,000 years ago when there were many animals, with the mammoth genome on an isolated island in the Arctic Ocean, where about 300 animals lived about 4300 years ago. According to the work, a small island population has lost many olfactory receptors, as well as urine proteins, which can affect social status and partner choice.
According to researchers, this work provides valuable information about what happens genetically with a population when it decreases.
"We believe that genomes affected by genomiccrisis, will lead to long-term consequences that will impede the restoration of the population, "the researchers write. In other words, efforts to conserve small and isolated populations may be inadequate, belated due to harmful mutations. The authors also say that those interested in the “resurrection” of animals should expect that the genomes of some mammoths can be negative, sometimes terrible mutations.
Resuscitation efforts by Church andother scientists are based on DNA extracted from giant hair balls found frozen in Siberia. It is believed that these continental species became extinct about 10,000 years ago due to climate warming and human activities.
Resurrection and price of conservation
Bioethics can argue about ethics for a long timeconsequences of resuscitation of extinct species. A new study published in Nature Ecology and Evolution may support the argument against. In their work, scientists argue that attempts to resurrect mammoths can lead to further loss of biodiversity, since the cost of resuscitation of dead species is much higher than an attempt to preserve the existing one.
Scientists have calculated that for every extincta species that may be resurrected in New Zealand, such efforts will result in the sacrifice of the salvation of as many as three existing or living species. This ratio is even worse in New South Wales and Australia, where the resources needed to return the five extinct species could be used to conserve 42 living species.
“Given the significant potential for lostopportunities and risks associated with the fact that a regenerated species can fill its niche in the ecosystem can hardly be justified by the current conservation of biodiversity, ”says Hugh Possingham, professor at the University of Queensland.
“Resuscitation may be useful to inspirea new science and for conservation, if we make sure that it does not reduce the resources that are allocated to preserve the existing nature, ”he adds. “However, in general, it would be better if we focus on the many species that need our help now.”
The woolly mammoth is not the only candidate for return.
A group called Revise and Restore leadswork on several projects to address the effects of extinction, as well as initiatives to save endangered species. Her flagship project is the restoration of a wandering pigeon, which became extinct at the beginning of the 20th century as a result of indefatigable hunting and destruction of the habitat by human forces.
The group developed a checklist of criteria.to determine if the species would be a good candidate for return. The criteria fall into approximately three categories: is it possible to resurrect a species from a scientific point of view in general? Can a resurrected species survive and thrive in the wild? What are the benefits of bringing a species back to life?
In the case of a wandering dove, the goal isrestoring regeneration cycles in the forests of East America to make them more diverse and productive. Forest restoration requires periodic disturbances, such as forest fires. Historically wandering pigeons have been a major player in the riots of natural forests.
“By restoring the ecological role of wandering pigeons, we can naturally restore and perpetuate reforestation cycles,” the group said in a statement.
Other resurrection candidates include bucardo, tilacin (marsupial wolf), rheobathrachus frogs, cave lion, Atlantic gray whale and, of course, woolly mammoth.
It seems like just answering the question what species are worthreturn from the dead, no. The world is getting warmer, habitats are disappearing, the environment is becoming dirtier, and the crisis of biodiversity is deepening. The return of species to life, despite the complexity of this task, could help us restore diseased ecosystems.