How do dogs know which direction to track?
Everyone knows dogs have super-sensitive noses and can track scents for miles. But how to they know which direction to travel? If a bloodhound is searching for someone, why doesn't it start travelling in the opposite direction 50% of the time, still following the trail,but moving towards the person's starting point? Does scent have some sort of directional indicators that say "person approached from this direction and travelled in this direction"? Does it have to do with the strength of the scent (weaker = older)? You wouldn't think the strength of a scent would be much different from one spot to a point a few feet away, but dogs do have exceptional noses. If anyone out there has a scientific answer, I'd love to hear it.
A dog's nose is sensitive enough to detect the minute differences between the scent of one step and the next. It does have to do with the strength of the scent just as you suspected. It is incredible, but very true!
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