Every outbreak across the globe today stems from a descendant of the medieval plague.
I laughed when Steven Spielberg said that cloning extinct animals was inevitable. But I'm not laughing anymore, at least about mammoths. This is going to happen. It's just a matter of working out the details.
We know African and Asian elephants can interbreed, and they're separated by 5 million to 6 million years.
Teeth actually turn out to be one of a couple of good sources of ancient DNA. The teeth, actually the enamel, is quite good at preserving the DNA, so it is a bit of time capsule so to speak.
Scientists have always thought that because mammoths roamed such a huge territory - from Western Europe to Central North America - that North American woolly mammoths were a sideshow of no particular significance to the evolution of the species.
You can go into caves, and they can maintain constant conditions of temperature and humidity over long periods of time, even though the outside temperature may be way above what it is inside the cave.
When I was a young boy, I used to gaze through the microscope of my father at the insects in amber that he kept in the house. And they were remarkably well preserved, morphologically just phenomenal.
It turns out that there are swaths of habitat in the north of Siberia and Yukon that actually could house a mammoth. Remember, this was a highly plastic animal that lived over tremendous climate variation.