A story through Reuters and the Economist tells of a study showing that Tibetan people have a gene that helps them adapt to the high altitude. It helps their blood carry enough oxygen without getting thicker with iron like our low lander blood does. This gene as it turns out was found in the DNA recovered from 41,000 year old bones in the Denisovan cave in Siberia. This ancient group appears to be distinct genetically from modern humans and Neanderthals, both of whom evidently also lived around there then, and while the Denisovans are no longer with us, some of their genetic material lives on in the Tibetans (and others). I wonder about the human yen for living in extreme environments, what we are seeking or liking from the high, cold, or hot places given the challenges of survival there. Many mutations have added up to yield an animal like us and here is one more that enables us to explore and live at the edge of our comfort zone.