I've noticed, like many others, that dogs hate bicycles and tend to bark or attack them and their riders.

From my observation it's not as simple as it first appears; sometimes I've noticed that dogs simply don't register a bike approaching them, and are then really surprised when nudged with the front wheel even though they've  seen it coming and presumably smelled the rider approaching too, and the rider was shouting and ringing a bell. In these cases, though, stamping a foot down works wonders.

It seems to be all about footfalls/vibration being the key factor that most dogs pay attention to. They see a person apparently gliding along without any obvious footfalls and it either freaks them out, or they completely ignore it and don't perceive it as a large object approaching.

My question is "why should this be?" What possible evolutionary reason is there for ignoring the sense of sight, smell and hearing in favour of vibrational cues? Is it that chasing prey through sunlit and dark areas renders sight less effective than vibration sense? Is it that in a wild pack of dogs, there's constant noise and confusion so footfalls are the most reliable way of sensing a threat?

What is going on here?