On Tue, 11 Sep 2012 10:17:37 +0100, Dave Cornwell
wrote:

. They are very tame and
associate gardeners with disturbing the ground and thus revealing food.

The story I was once told was that Robins evolved in the wild as
scavengers. Their "niche" was to follow animals, boars for example,
that disturbed the soil and then nip in and get the small insects and
grubs that had been disturbed. They have just transferred this
behaviour to gardeners.

I have no idea if it's true or not, but it does sound plausible.

Ian
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