Even the temperature of 0 degrees humanity can live?
If someone even conditions, it seems to be viable. For example, the case in the Middle East of the desert sometimes temperature is greater than 0 degrees, local people have been living without being heat stroke. Why? It's due to "low humidity".
Also desert is apt to be high temperature, the humidity is low. In this case, the sweat from the human body is immediately evaporated and the time of vaporization heat (heat to take at the time of evaporation) will cool the body. Since the water vapor that has been warmed up during the day that there is no such as remaining in the night, the night will be cool.
On the other hand, not to heat stroke "constitution" it is also important. Although that cause the cranial nerve to the abnormality at a high temperature is the main cause of heat stroke, endurance of the nervous system to the heat, in other words the difference of heat stroke [prone people] and [less likely people] are determined to genetic seemed there, there are Zubutoku Ikinukeru people even in hot and humid environment, it means that.
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