What about animals that went extinct because of man's careless slaughter? For example: the passenger pigeon. Like the bison, passenger pigeons were super abundant and a native animal to America. While many species of native birds are threatened because of dwindling habitat or the introduction of competition from abroad, the passenger pigeon was wiped out for its commercial value.
Being a native bird that did not die off because it was outdated by Mother Nature, but rather eliminated by an unnatural cause (man and guns), shouldn't it be our moral duty to reintroduce species with histories such as this? Righting a wrong, so to speak? What's more ethical than that?

Scientist asks "Are we [reviving lost species] to create a zoo or recreate nature?" Blather! Who is this "we" refered to? Grammatically, there is no antecedent. Is the reader to assume that all of humanity must make a common decision about this? Poppycock! Not only CAN there be multiple different decisions about this, but there almost certainly will be.
Do not think that some bleeding edge group will ask their (government) sponsors what to do. Think, instead, that any thing that bleeding edge scientist can do in THIS decade, will be commonplace in 60 years. Soon hobbyist groups can sequence the genes and impregnate an elephant in the hinters anywhere in south asia or africa. It WILL happen.

I think we would do better to concentrate on limiting the numbers of species that we are directly driving to extinction, rather than acting after the fact.
Whatever happens in the future, the world and life will continue in some form until the sun becomes a red giant, but if we destroy our ecosystem, nothing will save us from extinction in a very short time.

The Mammoth was mostly just hunted to death by humans. It existed not too long ago so it's not like it would be completely out of place in the environment. Same with the other species humans have killed off. If you can, why not?

I think it is cool to see a living mammoth. I have a problem with bringing back animals that try to eat me (aka; Jurassic Park).

Very misleading title. I wish the author would name one extinct species that has been brought back to life. Just one.

To whom it may concern:
Don't bring back velociraptors. Please.

Technology is close to a stage where geneticists would be capable of constructing full genomes of complex animals using synthetic base pairs (from scratch) rather than cloning, such as proposed for the wooly mammoth. Just because the capability exists does not imply it should be attempted. I'm sure there are researchers who would make a case for re-creating Homo neanderthalensis, for example, and other geneticists who would not hesitate to create a human embryo to-order. The considerations are beyond anything mankind has ever faced. It's not just a matter of right or wrong but rather the consequences — societal and ecological — of employing the technology, especially those that cannot be foreseen.

Public zoos became popular because of the humanist Victorian desire to exhibit man's mastery over Nature. Bringing a living woolly mammoth to life would still serve a higher purpose. It would serve to focus both funding and science on a subject whose "spinoff" benefits would likely to make a significant to several fields, including medicine, genetics, biology, archeology, etc. The hardest obstacle in science is to get enough attention and resources focused on a well-defined goal., It is a major reason why science makes huge leaps in times of war. While the resurrection of an extinct species may not be very worthwhile of and in itself, sometimes we have to step back and look at the larger picture.
BTW. The extinction of the passenger pigeon was primarily due to an evolutionary dead end that used massive numbers in a compact space as a way to deal with predators. that resulted in an animal whose pattern was for the population to explode, use up all available resources, then crash. Yes, there were additional factors, such as competition with agriculture, being a particularly tasty squab, and disease that were secondary causes, but the current theory is that evolution had created an animal which had to exist in billion-scale quantities in order to successfully reproduce. So in a population that was already noted as a boom and crash species, there was added pressures from people. But in the end it was Drunkard's Walk that killed the passenger pigeon.

Earth's ecosystem, if healthy, can continually adapt to natural extinctions. Although there would be a significant "wow" factor in such an accomplishment, the reasoning for expending likely huge funds, time and resources in reintroducing extinct species strikes me as feeble. If so-called "de-extinction" competes in any way with our pursuit of strengthening the ecosystem and reducing man-caused pressures that cause inordinate extinctions, our scientific interest should remain focused on the latter.