Culture matters
Tyler contemplates the resurrection of neanderthals and woolly mammoths:
The new claim is that a woolly mammoth could be regenerated for as little as $10 million. The basic technique, as I understand it, is reconstructing the genome of the mammoth and modifying the DNA in the egg of a modern elephant and bringing the final-stage egg to term in an elephant mother. It is noted that the same will be possible with Neanderthals, as it is expected that their genome will be recovered and sequenced shortly.
I'd be happy to see this done in either case--and not just because, as a commenter notes, having killed them off we maybe have an obligation to bring them back. But what does it mean to "bring them back?" Sure, I want to know what a neanderthal looks like, but I'm more interested in what a neanderthal acts like, how they think, what they have to say, if indeed they can talk.
But it's not possible to resurrect what a neanderthal was like, because a lot of what made them neanderthals was being raised by other neanderthals. "Wild children" have a full complement of human DNA, but they're crippled as humans. Imagine assessing humanity based on the behavior of a child raised by baboons--or, for that matter, by really intelligent aliens.
That's less of a problem, but still a problem, for woolly mammoths, or any creature that cares for its young. Maybe we should concentrate on trilobytes.