for National Geographic News
Today the only place to see woolly mammoths and people side-by-side is on The Flintstones or in the movies.
But researchers are on the verge of piecing together complete genomes of long-dead species such as Neandertals and mammoths. (See a brief overview of human genetics.)
So now the big question is, Will we soon be able to bring such extinct species back to life?
Researchers are divided over how they might try to do this and whether it's even feasible. (Related: "Woolly Mammoth Resurrection, 'Jurassic Park' Planned [April 8, 2005].)
At the core of this issue is DNA, which encodes the thousands of genes that tell cells how to build themselves and keep running.
Researchers already have deciphered the complete gene sequences—or genomes—for many living species, including humans, dogs, and mice. (Related: "Dog Genome Mapped, Shows Similarities to Humans" [December 7, 2005].)
The DNA of long-extinct species can also be preserved—in bones or bodies found in dry caves or inside ice, for example.
"Retrieval of DNA from ancient specimens is relatively easy now," said Alan Cooper, of the University of Adelaide in Australia.
Even though such DNA has degraded into thousands of small pieces, researchers can still read these fragments and piece together much of the original genetic instructions.
Dead to Return?
So many researchers think that assembling the genome of Neandertals (often spelled "Neanderthals") or mammoths is just around the corner.
A team led by Stephan Schuster and Webb Miller at Pennsylvania State University and Tom Gilbert at the University of Copenhagen is working on the genome of woolly mammoths preserved in the Siberian permafrost.
SOURCES AND RELATED WEB SITES