What it is that enables a dog to separate other animals into “dog” and “not-dog”, even from a distance? My terrier can see another animal 100 yards away or more, and knows instantly if he is looking at another dog. No matter what the breed – from Yorkies to Great Danes by way of spaniels, boxers, labradors, rottweilers, greyhounds and generic mongrels, there is something that tells him it is a dog. His response to cats, horses, rabbits, sheep and even the occasional fox that we encounter on our walks is totally different – to him, they clearly fall into the “not-dog” category. Much of the time he is in the car and they are outside, which suggests a visual cue. Any idea what it might be?
Darius Bartlett, Cork, Ireland
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