My Clan Crest

Taken from the Pollock Clan Crest, as well as the Crest and Motto on the Pollock Coat of Arms, or... what I know as the Pollock Coat of Arms.
After having perused the Court of the Lord Lyon website, I am now less certain of what I thought I knew about Heraldry and the historical possibilities associated with my Surname.
That said, I still like the imagery and the motto.
"At the end of his seven years one born to it will stand at the start of knowledge, and leaning a fond ear to the drone, he may have parley with old folks of old affairs." -N. Munro