My wife and I are not particularly outdoorsy, having both grown up in cities/suburbs in the US. So actually both of us probably should be at least somewhat wary of being alone in semi-wilderness. But maybe it's an example of male overconfidence that the suggestion calls up images of Walden for me, but probably Unsolved Mysteries for her. I'm certainly not saying women should be afraid of being alone outdoors, but there is a pretty pervasive cultural perception that lone women are more vulnerable than lone men in many situations. It doesn't help that, for the majority of people, the most famous female "adventurer" they've heard of is Amelia Earhart, whose disappearance overshadowed all her pioneering achievements.