I attended a small neurology conference at MIT a few months ago and professor Church was there. He was very friendly and a few of us peppered him with questions about bringing the Woolly Mammoths back. He heads the Woolly Mammoth de-extinction project that Stuart Brand founded.
He is utterly fascinating. He wants to bring a million of them back to the Yukon for the sake of the environment, among other things. He says from a scientific point of view, they're ready. I asked how they would prevent poachers given their tusks. He said he would bring them back without tusks.
Anyway, he's on 60 Minutes tomorrow wrt reversing aging, which he does on mice in their lab at Harvard. He is turning into an unlikely pop culture icon.