Science Photo Library - LEONELLO CALVETTI via Getty Images
私たちは映画『ジュラシック・パーク』から何も学ばなかったのか？
ハーバード大学のジョージ・チャーチ教授は2月16日、ガーディアンに「最終氷期に絶滅したマンモスのある形状を今後2年で蘇らせることができる」と語った。目標はマンモスとそれに最も近い現存する近縁種「アジアゾウ」の胎芽を作ることだ。
チャーチ教授は「私たちの目標はゾウとマンモスのハイブリッド胚を作ることです。実際はマンモスの形質を持つゾウのような動物になるでしょう」と、ガーディアンに語った。
チャーチ教授は2016年、ハフィントンポストUS版に「ツンドラの凍土に保存されたマンモスのDNAを採取し、それをアジアゾウのゲノムに組み込んで作る」と説明した。最も近い種同士なので、現代に両方が存在したとしても繁殖していけると、チャーチ教授は語った。
このプロジェクトには多くの批判がある。たとえば自然保護活動家は「脱絶滅」という考え方を「ギミック」と呼び、現存する種を保護する努力から注意をそらすものだと述べている。一方チャーチ氏は、この取り組みによって、絶滅に瀕したアジアゾウを遺伝子操作でもっと寒さに適応できるようにし、暮らせる場所を増やすことで保護する数を増やせると話している。
チャーチ教授は2016年、ハフィントンポストUS版のインタビューで「私はこの動物を耐寒性のあるアジアゾウと呼んでいます」と述べた。
チャーチ氏は、ロシアとカナダのツンドラに生息するハイブリッド生物を想定していると述べ、その存在で気候変動の影響を食い止めることができると主張した。チャーチ氏は科学雑誌『サイエンティフィック・アメリカン』に次のように寄稿した。
マンモスは以下の方法でその地域の寒さを保つことができる。 （a）マンモスは枯草を食べるため、春の草に太陽光が届くようになり、深い根の腐敗を防げる。（b）マンモスが太陽光を吸収する木々を倒し、反射光が増える。（c）マンモスは覆っている雪をかきわけるので、凍った空気が土に浸透する。また密猟者が北極のマンモスを標的にする可能性は、アフリカゾウに比べてずっと低いと思われる。
チャーチ教授が率いる研究チームは、ハイブリッド動物を人工子宮で育てようと考えている。生きたメスのゾウを使うと倫理的に問題があるためだ。しかし人工子宮には深刻な欠陥があると心配する声もある。
マンチェスター大学のマシュー・コブ教授は「チャーチ教授のチームは胎芽を『人工子宮』で育てる計画をしていますが、それは控えめに言っても野心的なものです。そこで生まれた動物は、誕生前の母親との一切の交流が奪われてしまいます」と、ガーディアンに語った。
ハフィントンポストUS版より翻訳・加筆しました。
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マンモス
Auction Of A Complete Woolly Mammoth Skeleton(01 of16)
BILLINGSHURST, ENGLAND - NOVEMBER 26: A woolly mammoth skeleton is displayed at Summers Place Auctions on November 26, 2014 in Billingshurst, England. The ice age mammoth skeleton, complete with tusks, fetched £189,000 to a telephone bidder. The woolly mammoth died out about 10,000 years ago. Errol Fuller, the curator of the sale, said: \'This is a virtually complete Mammoth skeleton with beautiful tusks, which makes it particularly rare. Its impressive size of 3.5 metres (11\'6) height and 5.5 metres (18\') long, suggests it may be a male Mammoth and may have weighed up to six tonnes in its lifetime\'. (Photo by Peter Macdiarmid/Getty Images) (credit:Peter Macdiarmid via Getty Images)
Auction Of A Complete Woolly Mammoth Skeleton(02 of16)
BILLINGSHURST, ENGLAND - NOVEMBER 26: A woolly mammoth skeleton is displayed at Summers Place Auctions on November 26, 2014 in Billingshurst, England. The ice age mammoth skeleton, complete with tusks, fetched £189,000 to a telephone bidder. The woolly mammoth died out about 10,000 years ago. Errol Fuller, the curator of the sale, said: \'This is a virtually complete Mammoth skeleton with beautiful tusks, which makes it particularly rare. Its impressive size of 3.5 metres (11\'6) height and 5.5 metres (18\') long, suggests it may be a male Mammoth and may have weighed up to six tonnes in its lifetime\'. (Photo by Peter Macdiarmid/Getty Images) (credit:Peter Macdiarmid via Getty Images)
JAPAN/(03 of16)
A 39,000-year-old female Woolly mammoth, which was found frozen in Siberia, Russia is seen upon its arrival at an exhibition hall in Yokohama, south of Tokyo, July 9, 2013. The mammoth will be on display from July 13, 2013 till September 16, 2013. REUTERS/Toru Hanai (JAPAN - Tags: ANIMALS SOCIETY TPX IMAGES OF THE DAY) (credit:Toru Hanai / Reuters)
ARCTIC-RUSSIA/MAMMOTHS(04 of16)
A boy looks at the skeleton of a mammoth in the Ice Age Museum in Moscow September 4, 2007. In Siberia\'s northernmost reaches, high up in the Arctic Circle, the changing temperature is thawing out the permafrost to reveal the bones of prehistoric animals like mammoths, woolly rhinos and lions that have been buried for thousands of years. Picture taken September 4, 2007. To match feature ARCTIC-RUSSIA/MAMMOTHS REUTERS/Sergei Karpukhin (RUSSIA) (credit:Sergei Karpukhin / Reuters)
ARCTIC-RUSSIA/MAMMOTHS(05 of16)
A boy looks at a mammoth reconstuction in the Ice Age Museum in Moscow September 4, 2007. In Siberia\'s northernmost reaches, high up in the Arctic Circle, the changing temperature is thawing out the permafrost to reveal the bones of prehistoric animals like mammoths, woolly rhinos and lions that have been buried for thousands of years. Picture taken September 4, 2007. To match feature ARCTIC-RUSSIA/MAMMOTHS REUTERS/Sergei Karpukhin (RUSSIA) (credit:Sergei Karpukhin / Reuters)
SCIENCE MAMMOTH(06 of16)
Scientists said on October 20 that they had dug up an entire 23,000-year old woolly mammoth, with the tusks shown here being loaded at the Jarkov site in this undated photo, from the Siberian permafrost and transported it intact and still frozen. Radar imaging techniques were used to \"see\" the creature in its icy grave, and is the first time a mammoth carcass from the Siberian permafrost has been excavated under such cold conditions, according to Dick Mol of the Museum of Natural History in Rotterdam.\n\nGAC (credit:Reuters Photographer / Reuters)
TAIWAN/(07 of16)
People in protective suits examine a frozen woolly mammoth named \"Yuka\" during a media preview at the Chiang Kai-shek Memorial Hall in Taipei November 6, 2013. The three-meter-long 39,000-year-old female mammoth, which died at the age of 10, was discovered in Siberia in 2010, according to the organisers. Yuka will be part of the exhibition \"The Frozen Woolly Mammoth\" from November 16, 2013 to March 2, 2014. REUTERS/Pichi Chuang (TAIWAN - Tags: SOCIETY ANIMALS) (credit:Pichi Chuang / Reuters)
TAIWAN/(08 of16)
People in protective suits examine a frozen woolly mammoth named \"Yuka\" during a media preview at the Chiang Kai-shek Memorial Hall in Taipei November 6, 2013. The three-meter-long 39,000-year-old female mammoth, which died at the age of 10, was discovered in Siberia in 2010, according to the organisers. Yuka will be part of the exhibition \"The Frozen Woolly Mammoth\" from November 16, 2013 to March 2, 2014. REUTERS/Pichi Chuang (TAIWAN - Tags: SOCIETY ANIMALS) (credit:Pichi Chuang / Reuters)
FOR USE WITH AFP STORY by Mira OBERMAN,(09 of16)
FOR USE WITH AFP STORY by Mira OBERMAN, Science-paleontology-mammoth-US-museum A replica of the world\'s best preserved wooly mammoth - a 40,000 year old baby named Lyuba who was discovered in Siberia in 2007 - is displayed for the media in a fossil storage room at Chicago\'s Field Museum on September 30. The Field Museum will be the first in North America to display Lyuba body, which is currently undergoing analysis in Russia, in an exhibit which opens on March 5. AFP PHOTO/Mira Oberman (Photo credit should read MIRA OBERMAN/AFP/Getty Images) (credit:MIRA OBERMAN via Getty Images)
A large mammoth skeleton is seen on display at Christie's in(10 of16)
FRANCE - APRIL 03: A large mammoth skeleton is seen on display at Christie\'s in Paris, France, on Tuesday, April 3, 2007. The bones of the creature, which lived in what\'s now Siberia before the last ice age ended about 10,000 years ago, will be auctioned April 16 along with those of a prehistoric cave bear, a woolly rhinoceros, and about 80 smaller fossils. (Photo by Antoine Antoniol/Bloomberg via Getty Images) (credit:Bloomberg via Getty Images)
Carcass of baby mammoth lyuba, discovered by a reindeer herder, yuri khudi, near the town of salekhard, north russia, the geological age of the find is 37,000 years, russia, october 23, 2007.(11 of16)
Carcass of baby mammoth lyuba, discovered by a reindeer herder, yuri khudi, near the town of salekhard, north russia, the geological age of the find is 37,000 years, russia, october 23, 2007. (Photo by: Sovfoto/UIG via Getty Images) (credit:SVF2 via Getty Images)
A large mammoth skeleton is seen on display at Christie's in(12 of16)
FRANCE - APRIL 03: A large mammoth skeleton is seen on display at Christie\'s in Paris, France, on Tuesday, April 3, 2007. The bones of the creature, which lived in what\'s now Siberia before the last ice age ended about 10,000 years ago, will be auctioned April 16 along with those of a prehistoric cave bear, a woolly rhinoceros, and about 80 smaller fossils. (Photo by Antoine Antoniol/Bloomberg via Getty Images) (credit:Bloomberg via Getty Images)
Pavel kosintsev of yekaterinburg's institute of plants and animals' ecology, r,a,s,; sergei grishin, head of the yamal-nenets shemanovsky museum and exhibition center; japan's professor naoki suzuki, (13 of16)
Pavel kosintsev of yekaterinburg\'s institute of plants and animals\' ecology, r,a,s,; sergei grishin, head of the yamal-nenets shemanovsky museum and exhibition center; japan\'s professor naoki suzuki, vice chairman of the scientific council for research on the yukagir mammoth; and french polar explorer bernard buigues, executive director of the international mammoth committee, (l-r) inspect the carcass of baby mammoth lyuba, discovered in permafrost near the town of salekhard, north russia, the scientists arrived in salekhard to attend a conference of paleontologists, russia, october 23, 2007. (Photo by: Sovfoto/UIG via Getty Images) (credit:SVF2 via Getty Images)
A mammoth skeleton is on display at the mammoth museum of the institute of applied ecology of the north, academy of sciences of the republic of sakha (yakutia), the skeleton was unearthed in churapchi(14 of16)
A mammoth skeleton is on display at the mammoth museum of the institute of applied ecology of the north, academy of sciences of the republic of sakha (yakutia), the skeleton was unearthed in churapchinsky ulus (region) in 1990, march 18, 2005. (Photo by: Sovfoto/UIG via Getty Images) (credit:SVF2 via Getty Images)
Remains of the fauna of the ice-age found in the transpolar area of russia are displayed at the 'mammoth chamber' exposition opened here, moscow, russia, november 2, 2004.(15 of16)
Remains of the fauna of the ice-age found in the transpolar area of russia are displayed at the \'mammoth chamber\' exposition opened here, moscow, russia, november 2, 2004. (Photo by: Sovfoto/UIG via Getty Images) (credit:SVF2 via Getty Images)
Remains of the fauna of the ice-age found in the transpolar area of russia are displayed at the 'mammoth chamber' exposition opened here, moscow, russia, november 2, 2004.(16 of16)
Remains of the fauna of the ice-age found in the transpolar area of russia are displayed at the \'mammoth chamber\' exposition opened here, moscow, russia, november 2, 2004. (Photo by: Sovfoto/UIG via Getty Images) (credit:SVF2 via Getty Images)
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