Don't get me on that subject, for all of our sakes... genealogy is an obsession, not a hobby...
http://www.genuki.org.uk/big/sct/ANS/This is a basic link you might find interesting, if you haven't done your homework...
Mine are all offshore, west-coast Scotland, back as far as we can trace, with (by estimated timeline) my Stewart (Appin) line being "rebels" that escaped after the defeat at Culloden... I have all the classic Hebridean names in my family - MacDonald, MacKenzie & MacLeod (MacLeod having direct links to the Vikings)... there is a strong Ferguson and Morrison representation, with a smattering of MacIver, Murray, MacRae, Campbell and even a Smith (which is what they would have been)... there is no direct Campbell-MacDonald link...
The "English" fixed the Highland names when "records" properly began, with the first British census (1841)... tradition dictates that you were known as "the son of your father" ie Mhich Domhnull = MacDonald = son of Donald, sort of... It is possible that a "surname" could change from generation to generation... My present "surname should be MacKenzie (son of Kenneth) ...
It would be best to have me chained down in some quiet, softly lit, padded room, with calm, soothing music, and powerful meds... at least until normality resumes...
Londoner...? accident of birth...
What's your Scottish family name, Bill...? It can be the difference between being a "sassenach" (lowlander, not Englishman) and a Highlander...!