 Temperature extremes do not affect them, and they do not sweat when hot (the author originally had them sweating in the 1985 short story The Shadow of the Starlight, but changed it for the book series).They view all activities they engage in as smaller parts of the greater pattern of things, and because of this and their long life span, they attain a level of excellence that no human can match in whatever skills they pursue.As a consequence of their perception of the patterns of reality, they can discern things about the physical realm that are hidden from humans.