While average temperature is up a bit, the typical high has not increased terribly much. Many record high days in my part of Canada still date to that 1936 hea

While average temperature is up a bit, the typical high has not increased terribly much. Many record high days in my part of Canada still date to that 1936 heat wave. You would adapt, a little bit. I personally find the swings in humidity between AC'd and non-AC'd environments to throw me off, like I don't know how much I should perspire. But I think people mostly just didn't actually thrive when it was really hot, historically. If nothing else, heat burden imposes real limits on the physical work both humans and domesticated animals can do. I can only assume in the distant past, like in the recent past when I worked landscaping, that many hot afternoons were basically write-offs, everyone lying in the shade. > Air-conditioning is not even a hundred years old High-intensity artificial lighting isn't much older than that. I think there's some analogy there. In the winter, people only got 6 hours of real work done each day, because they only had 6 hours or so of daylight. The way we construct artificial environments with ideal working conditions, is a major component to modern prosperity.