Advances in molecular biology are allowing scientists to \u201cchallenge extinction\u201d by creating a new field of biology called \u201cde-extinction;\u201d but should we bring extinct species back to life?<\/p>\n
In 1914, the last passenger pigeon<\/a> died and was shipped to the Smithsonian Institution for preservation.\u00a0 Throughout the 19th<\/sup> and early 20th<\/sup> centuries, passenger pigeons were the most numerous of all birds in the U.S., numbering in the tens of millions, but hunting and habitat destruction decimated the species, leading to its extinction in 1914.<\/p>\n Today, scientists are working on a way to resurrect the passenger pigeon and other extinct species using a new form of molecular biology called de-extinction<\/a>.\u00a0 Using DNA retrieved from extinct species, scientists are now exploring projects which would \u201cde-extinct\u201d formerly extinct species and bring them back to life once again.\u00a0 Possible de-extinction species include the Woolly mammoth, Tasmanian tiger, Dodo bird, Gastric-brooding frog, Pyrenean ibex, Carolina parakeet, Moa, Woolly rhinoceros, and Saber-toothed tiger.<\/p>\n The first-ever public conference exploring the revival of extinct species was held in Washington D.C. last week, hosted by The National Geographic Society<\/a> in conjunction with TEDxDeExtinction<\/a> and Project Revive & Restore<\/a>. \u00a0Project Revive & Restore is currently working with de-extinction scientists around the world to select species for \u201crevival\u201d based on criteria such as practicality and desirability.<\/p>\n The first project in the U.S. involves the resurrection of the passenger pigeon using DNA from museum specimens such as \u201cMartha,\u201d the very last passenger pigeon, on display at the Smithsonian.\u00a0 The passenger pigeon was chosen for its \u201ciconic status and its relative practicality\u201d according to Revive & Restore\u2019s website<\/a>.\u00a0 Additionally, \u201cits DNA has already been sequenced,\u201d allowing the \u201cmiracle of resurrection\u201d to begin.\u00a0 According to Revive & Restore, \u201cthe work will proceed by stages over the coming months.\u201d<\/p>\n Ben Novak, a passenger pigeon and ancient DNA expert, is currently working full-time with Revive & Restore to \u201crefine the sequencing of passenger pigeon DNA\u201d as well as return the passenger pigeon back to life.\u00a0 Using DNA from extinct passenger pigeons and comparing it to the passenger pigeon\u2019s closest living relatives, band-tailed and rock pigeons, Novak and other scientists working on the project will \u201cbegin the process of converting viable band-tailed DNA into viable passenger pigeon DNA.\u201d\u00a0 Scientists will use that DNA to create live passenger pigeons.\u00a0 Those birds will then be bred to create more birds, which will eventually be returned to the wild.<\/p>\n VIDEO:\u00a0 http:\/\/www.youtube.com\/watch?feature=player_embedded&v=TQ8TlUxiqgY<\/a><\/p>\n But will these \u201cnew\u201d passenger pigeons truly be passenger pigeons?\u00a0 As Novak says, \u201cIf it looks like a passenger pigeon and behaves like a passenger pigeon, is it a passenger pigeon or does it have to be an exact duplicate of the genomes?\u201d<\/p>\n Just one of the many questions now being raised in the field of de-extinction.\u00a0 But beyond the feasibility and logistics of reviving extinct species, probably the biggest question being raised concerning de-extinction involves ethics\u2014are we \u201cplaying God\u201d by resurrecting extinct species?<\/p>\n Scientists are divided on de-extinction.\u00a0 Some believe humans were already playing God when they drove certain species to extinction through hunting or other human-related actions.\u00a0 Still others believe we should leave well enough alone; that endangered species and extinct species are just part of the natural process.<\/p>\n Carl Zimmer, an award-winning science writer and author of 13 books dealing with evolution and related topics, believes that \u201cthe rate at which species are going extinct\u201d is continuing to increase \u201cdue to us\u2014to our hunting, logging, and other actions that leave species struggling to hold on to existence.\u201d\u00a0 He believes that if we continue along these lines of action, \u201cwe could jack the extinction rate to levels that life has achieved only five times in the past half billion years<\/a>.\u201d<\/p>\n In addition, Zimmer says that because \u201cthe whole conservation movement is organized around the proposition that biodiversity is something worth saving\u2014that when a species goes extinct, it can leave a hole and its ecosystem may suffer\u2014we lose the opportunity to investigate its biology and discover some fascinating piece of natural history or even find a valuable molecule for curing infections or sequencing DNA.\u201d<\/p>\n So is de-extinction a \u201ctool for slowing or reversing this trend?\u201d\u00a0 According to Zimmer, \u201cthat\u2019s a good question.\u00a0 But one thing\u2019s for sure.\u00a0 We\u2019re not playing God.\u00a0 We\u2019re coming to terms with our own powers, as well as the unexpected results of our actions.\u201d<\/p>\n Other scientists are concerned, however, that putting enormous sums of research monies into de-extinction will take away from normal conservation efforts.\u00a0 Additionally, they are concerned that de-extinction could cause a laissez-faire attitude towards threatened and endangered species, which may actually increase extinction rates.<\/p>\n So should we bring back species that could potentially threaten us or upset entire ecosystems, and if we do bring them back, what will we do with them?\u00a0 Will we literally create Jurassic Parks around the world to hold them?\u00a0 Efforts are already underway in Siberia to create a Pleistocene Park, as well as in the Netherlands (Oostvaardersplassen) and Hawaii (Makauwahi Cave).\u00a0 And if some of these resurrected species are returned to a \u201cnatural state,\u201d how will they affect the balance of current ecosystems?<\/p>\n Too many questions without answers.\u00a0 The bioethics of de-extinction must be carefully considered before proceeding with these projects.\u00a0 As Marilyn Renfree of the University of Melbourne said, \u201cthe reasonable response by scientists eager to know about these extinct species should be not to produce such an animal back to life, but learn more about the species from its genetic makeup.\u201d<\/p>\n There was a reason these species went extinct.\u00a0 Let\u2019s not rush to resurrect them without considering all the possible consequences or we just might be the next\u00a0 species to become extinct.<\/p>\n