Line up a bunch of Scottish people with English people and you won't be able to pick them apart reliably because they've evolved together on a pretty small island. Contrast that by lining up people who are Asian with people who are African. There's the difference.
There is no real scientific definition of race. It's one of the problems. But, I still don't think anyone could ever say Scottish and English are 2 different races. It's like saying Albertans and British Columbians are different races. A man made line on a piece of land doesn't truly separate the inhabitants of that land in any meaningful way.
My English roomate thought the handyman was racist when he told her she should go back to England. They're both white. He wasn't being racist, he was being a biggot.
Well Genetically they are pretty different with different characteristics. And White isn't a race anywhere but North America, the same with Black.
Albertans and British Columbian natives may very well be different natives (I don't know enough about that aspect of their histories)
But You make some odd distinctions, Any line in the dirt doesn't seperate inhabitants in a meaningful way, be it India and China or Scotland and England.
But in both cases it becomes fairly easy to distinguish a large group from one area with a large group from another area, even if the individuals could be difficult to classify.
Scottish people have a VERY different genetic ancestry to English people, not the least of which being the English people were Romanized and thus have had a vastly expanded gene pool (with entrants from as far off as Persia) for alot longer. Then the Scottish have their own different genetic history. They only began to intermingle a few hundred years ago.
While race is certainly a ficticious creation, visible genetic markers (Skin colour, hair colour, eye colour, facial features) can be used to quickly judge lineage with all the negative stereotypes about it.
Let me put it this way, "Blacks" and "Whites" in the US have been intermingling in as great or greater quantities than English and Scots in Britain for about the same amount of time.
Does that mean its impossible for Blacks and Whites in the US to be racist to each other? Does that mean its impossible to tell Blacks and Whites apart?
On a case by case basis, sure racism is pretty hard when alot of Blacks and Whites easily pass as the other "Race". But its a pretty narrow view of looking through North American eyes to not realize that we see the races that come up in our day to day lives only.
I mean, I can't tell a native person from european descended person 90% of the time. Does that mean natives aren't a race? And thats with me growing up next to a reserve.
Scotland and England are mixed, not just with eachother, but with other groups. Celts, Picts, Vikings, Romans, Saxons.... the list goes on and on. Even if I were to agree that Scotts and English haven't bred with eachother (which I don't), they were a mix already.
Look up a definition of race and it will say something about distinct physical characteristics (like hair color, skin color, eye color, bone structure, all of which are not significantly different between English and Scottish as a group even if it is between individuals) and it will say something about they've descended from a common lineage (which could be argued either way when it comes to English and Scottish, but it could also be used to say that my family is a race which is obviously absurd). It is a completely arbitrary man made definition and I have yet to see many accept that arbitrary definition to count "English" as a race.
I really don't understand why it is so offensive that English and Scottish be simply ethnic groups. I don't know why people want them to be so different from eachother when they really aren't all that different. What is the appeal of being a Race? If they are all races then we can just remove the words nationality and ethnicity from the English language because they are no longer needed. We can all just be races. Next time someone asks me my race, I'll say Canadian.... or maybe British Columbian.... or maybe even Kamloopsian.
I have a simpler idea. Instead of trying to define race, why don't we just look up the definition of "Scottish" and "English"? I'm betting you'll see words like "nation" "culture" "ethnic group", but seldom will you see "race".