TIME­LINE: AN­I­MALS WE’VE CLONED

BBC Earth (Asia) - - Update -

1894

Ger­man bi­ol­o­gist Hans Dri­esch takes a two-cell sea urchin from the Bay of Naples and shakes it in beaker of wa­ter. The cells part, giv­ing rise to two, in­de­pen­dent but iden­ti­cal, sea urchins.

1902

Hans Spe­mann, another Ger­man sci­en­tist, uses a fine hair from his baby son to split a sala­man­der em­bryo in two. The re­sult: two am­phib­ians for the price of one.

1952

In the US, Robert Briggs and Thomas King per­form a suc­cess­ful nu­clear trans­fer, by mov­ing a nu­cleus from an em­bry­onic frog cell into an egg cell whose own nu­cleus had been re­moved.

1962

In­stead of us­ing nu­clei from frog em­bryos, Ox­ford bi­ol­o­gist John Gur­don takes them from adults, demon­strat­ing that a dif­fer­en­ti­ated nu­cleus still has the power to build an en­tire an­i­mal.

1963

Chi­nese em­bry­ol­o­gist Tong Dizhou ap­plies the same tech­nique to fish, though his work, orig­i­nally pub­lished in his na­tive Chi­nese, does not re­ceive much at­ten­tion be­yond China.

1996

The cloning of Dolly the sheep builds on Gur­don’s method, show­ing that the nu­cleus from a dif­fer­en­ti­ated cell re­tains the abil­ity to make an en­tire an­i­mal from scratch, even in mam­mals.

1999

A team led by Prof Ger­ald Schat­ten cre­ate Tetra, a rh­e­sus macaque, us­ing em­bryo split­ting. Here, the cells in the em­bryo are split af­ter reach­ing the eight–cell stage to cre­ate four iden­ti­cal two-cell em­bryos.

2001

Re­searchers at Texas A&M Uni­ver­sity cre­ate the first cloned pet, us­ing a cell from a brown-and-white tabby cat called Rain­bow to make

‘CC’ (aka ‘Copy Cat’ or ‘Car­bon Copy’).

2001

Sci­en­tists at Ad­vanced Cell Tech­nol­ogy in the US are the first to clone an en­dan­gered species.

Noah the gaur, a species of wild ox na­tive to Asia, dies from dysen­tery af­ter two days.

2005

Con­tro­ver­sial South

Korean sci­en­tist Hwang Woo-Suk uses the ear cell from an Afghan hound to make Snuppy, the world’s first cloned dog. A Labrador acts as sur­ro­gate mother.

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