I guess increased night-time travel could be a result of a genetic change - imagine if there were a particular group of deer who, for some reason or another, had an eye dysfunction that inhibited their daytime vision (maybe their iris wouldn't close far enough to block out the daytimesunlight, causing them to spend their days hiding in the shade, to keep from being blinded by the sun). As a result, this group would tend to travel/feed primarily during low-light hours, and overnight. Obviously, these traits would indirectly lead to this group being tougher to hunt, given their low levels of daytime movement.

In that particular area, hunters would harvest a higher percentage of the deer with excellent day-vision, leaving the nocturnal herd to reproduce and pass on that genetic material.

I guess that would be a plausible scenario where hunting could speed the evolutionary processes by leaving deer to reproduce that are genetically programmed to be tough to hunt.

Interesting to think about, eh?