Inside the Animal Mind: Can dogs really tell the time?
28 January 2014 Last updated at 13:24 GMT
Can dogs tell the time? The question is familiar to many dog owners whose pets seem to be able to sense when someone special is due home.
A BBC documentary team has been keeping an eye on Jazz, a Hungarian Vizsla from Lesmahagow, who seems to know when his owners are due home.
But how does he do it? BBC Scotland's science correspondent Kenneth Macdonald finds out.
You can watch Inside the Animal Mind on BBC Two Scotland at 20:00 on Tuesday, at 21:00 on BBC Two in the rest of the UK, and on the BBC iPlayer for one week after transmission.