We can keep them in zoos. However, in order to create natural breeding populations of extinct species we would need to have habitats for them. Much of extinction is not "species level" but "environment level". Extinction of some key species implies extinction for many others.
With regard to mammoths and other long-extinct species, it is still a question of "could we". There may be some DNA in the teeth and tissues, but it is probably somewhate denaturized, not enough operational DNA left to create a mammoth, even if the remainder could be replaced with elephant DNA. We still have no technical tools that can accurately "read" a single strand of DNA and do it again and again, to extract redundant information from many strands. In addition, the weaker hydrogen bonds in some areas will unravel for all of the strands, so redundancy doesn't work. There may be enough DNA to analyze it and determine the kinship relations of mammoths to elephants. It is not likely that there will be enough to make a mammoth.
What we most definitely should do is to extract DNA from as many individuals of as many living species as possible and store it at liquid nitrogen temperatures. Not just vertebrates, but everything from bacteria on up. That way, in a distant future when the north pole has an ice cap again and the earthbound human population has declined, we can recreate a small amount of the equitability lost in this time.
The big question is: how many synthetic species should we make and what should we do with them? Do we need a lot of glowing green monkeys with jellyfish genes? (see last week's science news). Once we know the connections between genes and enzymes and the development sequence, we will have a really interesting tool for experimental biology. Are we going to try to create megaraptor de novo from chickens or emus? This capability is a lot closer than the scenario in Jurassic Park.
Mike Hickman wrote:
is no longer the question of "could we?" but "Should we?".
Undoubtedly many of you have heard of the attempt to clone mammoth.
I would like to you what you think about it.
-Mike (A.K.A. MegaRaptor)
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