The whole concept of interplanetary calendars and time keeping will be interesting to see how it's resolved (assuming our species lives long enough for it to ma

The whole concept of interplanetary calendars and time keeping will be interesting to see how it's resolved (assuming our species lives long enough for it to matter). It makes the current mess of time zones, daylight savings/summer time and leap seconds seem trivial by comparison. At least the Martian day isn't very different in length from the Earth day, but how will our biology adapt to colonization on a planet where, say, a day is 15 hours or 36 hours?