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Wednesday, November 26, 2008

Raising The Dead

If, as I did, you spent much of your youth reading about creatures of the past, and especially if you had a chance to frequent museums, as I did the Page Museum at Los Angeles' La Brea Tar Pits, the idea of seeing some of the large land mammals which went extinct within the last 50,000 years brought back to life can't help seeming a bit attractive.

Who could resist the chance to see an American Mastodon (above) or a Smilodon, or "saber-toothed cat" (below) alive again?


Scientists are increasingly thinking that it would in fact be possible to produce live specimens of recently extinct mammals, such as the Woolly Mammoth, which died out in Europe and America (like the above creatures) only around 8,000 B.C.


The cause of these extinctions was probably dual: changing climate after the end of the last glacial period, and excessive hunting by humans. That virtually all large mammal species (among them the American Horse and American Camel) other than the American Bison vanished from North America shortly after the flourishing of human populations here is probably not entirely a coincidence. (A similar pattern occurred in other parts of the world, notably Australia where a number of large marsupial species died out right after the arrival of humans.)

Given how recent these extinctions were, there's fairly "fresh" genetic material still around from them, and fairly close living relatives around to serve as surrogate parents, so of course as genetic technology advances scientists have become increasingly interested in trying to bring back one or more of these recently extinct species by means of using original genetic and cloning type procedures. The New York Times reports:
Scientists are talking for the first time about the old idea of resurrecting extinct species as if this staple of science fiction is a realistic possibility, saying that a living mammoth could perhaps be regenerated for as little as $10 million....

A scientific team headed by Stephan C. Schuster and Webb Miller at Pennsylvania State University reports in Thursday’s issue of Nature that it has recovered a large fraction of the mammoth genome from clumps of mammoth hair. Mammoths, ice-age relatives of the elephant, were hunted by the modern humans who first learned to inhabit Siberia some 22,000 years ago. The mammoths fell extinct in both their Siberian and North American homelands toward the end of the last ice age, some 10,000 years ago.

Dr. Schuster and Dr. Miller said there was no technical obstacle to decoding the full mammoth genome, which they believe could be achieved for a further $2 million. They have already been able to calculate that the mammoth’s genes differ at some 400,000 sites on its genome from that of the African elephant.

There is no present way to synthesize a genome-size chunk of mammoth DNA, let alone to develop it into a whole animal. But Dr. Schuster said a shortcut would be to modify the genome of an elephant’s cell at the 400,000 or more sites necessary to make it resemble a mammoth’s genome. The cell could be converted into an embryo and brought to term by an elephant, a project he estimated would cost some $10 million. “This is something that could work, though it will be tedious and expensive,” he said.
I must admit, I find this a rather exciting idea. However, it seems that no sooner do people come up with the ability to do something like this than they get other ideas:
The same would be technically possible with Neanderthals, whose full genome is expected to be recovered shortly, but there would be several ethical issues in modifying modern human DNA to that of another human species.
Love the charming understatement of "there would be several ethical issues in modifying modern human DNA to that of another human species", eh?

Oh, but fear not. We've got some deep thinkers here who are working hard to make sure that they don't engage in any research that treads ethically thin ice:
But the process of genetically engineering a human genome into the Neanderthal version would probably raise many objections, as would several other aspects of such a project. “Catholic teaching opposes all human cloning, and all production of human beings in the laboratory, so I do not see how any of this could be ethically acceptable in humans,” said Richard Doerflinger, an official with the United States Conference of Catholic Bishops.

Dr. Church said there might be an alternative approach that would “alarm a minimal number of people.” The workaround would be to modify not a human genome but that of the chimpanzee, which is some 98 percent similar to that of people. The chimp’s genome would be progressively modified until close enough to that of Neanderthals, and the embryo brought to term in a chimpanzee.

“The big issue would be whether enough people felt that a chimp-Neanderthal hybrid would be acceptable, and that would be broadly discussed before anyone started to work on it,” Dr. Church said.
I'm sorry, perhaps I shouldn't be flip and derisive, but in the words of my generation: Is this guy for real?

Does he really imagine that the big moral objection that people have to the idea of cloning Neanderthals is just a matter of whether a human egg or chimp egg is used?

The Neanderthals were around until about 25,000 years ago. They made complex tools, wore simple jewelry, made clothes, buried their dead, used fire, and there's fairly strong evidence that they also created art and had equal speech abilities to modern humans. One of the main controversies about Neanderthals is whether they are a separate species in genus homo or a separate sub species within homo sapiens (homo sapiens sapiens vs. homo sapiens neandertalis).

Even leaving aside thorny religious questions (of which I think there are definitely many -- given that I don't think creating genetic knock-offs of modern humans is remotely acceptable, and also given that the evidence is decent that the Neanderthals were themselves religiously aware in some sense, and thus not to be taken as a non-entity in the question) this seems like an appalling idea from a strictly humanitarian perspective. Create one or more "resurrected" members of an extinct group of humans as a scientific and technical stunt? A group of humans which clearly had mental and physical (and I would assume thus emotional) characteristics not so different from our own -- and yet almost certainly different as well.

Would the researchers "own" these Neanderthals? Would they be citizens with their own rights? What kind of life are you setting someone up for by artificially bringing him into the world 25,000 years after those like him died out, and making him a curiosity among a sea of those similar yet not the same?

Don't get me wrong, I can certainly find the idea of meeting other types of humans interesting, but artificially creating them strikes me as not only irresponsible, but inhumane.

Well, I'm apparently not the only one who had some ethical questions about the article, because the New York Times chose to run an editorial about the article. Their ethical concern?
The first mammoth would be a lonely zoo freak, vulnerable to diseases unknown to its ancestors. To live a full and rewarding life, it would need other mammoths to hang out with, a mate to produce a family and a suitable place to live. The sort of environment it is used to — the frigid wastes of Siberia and North America — are disappearing all too fast...

If scientists do bring back a few mammoths, we suspect our warming world won’t look any more hospitable than the one that did them in.
Yes, they ponder whether it would be moral to bring a woolly mammoth into a world with global warming.

Do you ever get the impression there are people with very different philosophical and moral compasses than your own in our country?

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