De-extinction
The methods (and ethics) behind bringing back extinct species have been hotly contested for as long as DNA has been understood. While there are many ideas, the general consensus is that the species must be recent - The odds of a tiny, fragile, female mosquito engorging itself on dinosaur blood, immediately trapping itself in amber, and staying preserved for >65 million years are too high for good results. Nonetheless, there have been many attempts at bringing back extinct creatures, even with some semi-successful results.
Breed-backA method for very recently-deceased species, this method uses genetically-similar animals to slowly breed back the traits of the extinct species until an almost-identical species is created. The most notable current example of this project is the Uruz Project, an attempt to resurrect the European wild cattle known as the Aurochs (extinct in 1627) back by selectively breeding its descendents - domestic cattle. The cow breed's genes will be further improved on by employing CRISPR and siRNA to stop additional un-Aurochs-like traits from being inherited in later generations ("True Nature Foundation" Aurochs Backbreeding).
CLone Editing
More similar to the Jurassic Park methods, clone editing involves creating a clone of an animal genetically similar to a recently extinct organism and selectively editing its genome to resemble the extinct creature more closely. Currently, Harvard scientist George Church is attempting to take an Asian Elephant embryo, edit 15 or so areas of its genome - make it a bit larger, give it woolly hair, subcutaneous fat, etc. - and create a Woolly Mammoth, born from an Asian Elephant (Chung 3). The animal wouldn't exactly be a Mammoth, but as a Woolly Mammoth genome has been fully sequenced, making a close copy is very possible.
Cloning
The first fully-verified, successful method - extinct animals have been (temporarily) resurrected by cloning. The Pyrenean Ibex was a wild goat species driven to extinction by competition with domesticated animals in January 2000. Jumping at the chance to save such a recently-destroyed species, scientists immediately began a project to clone them back, and in 2003, it actually worked - one Pyrenean Ibex was successfully brought to birth, and an extinct species lived again - unfortunately, for only a brief time. The clone died 10 minutes after its birth due to lung defects (Zimmer). Nonetheless, cloning technology has only improved within the last twelve years, and as far as de-extinction science has gone, cloning has had the only successful result.
|
|
|