hyper sensitive sensory system

I know dogs have an acute sense of smell. And their hearing is also superior to humans in some respects. I imagine it all works together beautifully, as a complementary package. What I'm wondering today is exactly how acute is that system? I mean, it's one thing for my dog to hear the milk truck coming 'round the corner at 3am -and bark in warning for the whole neighborhood. And of course, the mailman gets a daily dose of "keep away from my territory" starting when he's 3 houses down on the other side of the street. But how hypersensitive are her senses to wake up at 5am when a coyote is padding down the middle of the street? And you know, me being the light sleeper that I am, I was immediately & rudely awoken so as to all the more quickly jump out of bed & take a look out the window at what intruder might be lurking nearby. Don't get me wrong, this time I wasn't disappointed. I'd started to think that the neighborhood coyote thing was an urban myth. But still. The twilight was silent -the birds weren't even singing yet. It's not like a coyote is clomping around in Doc Marten's or unlaced high tops. Padding might even be too loud of a description. Or was it the scent? Funny that she couldn't care less about the neighborhood fox. Ever. And the fox is the stinky one. It's the cat who get's all territorial with the fox. I loved that the coyote stopped to pause & consider our house more than once. Was it tempted to break that Cody mandated perimeter out of curiosity or defiance? Or was it hearing that vociferous warning & moving on down the line to less injurious pastures? Personally, I think our dog would sooner play than attack (not that I'm testing that theory out on the mailman anytime soon.) She's just that kind of gentle soul. Big old bark, no bite at all. And that's fine with me.