If we look at many many other mammals it is very clear that there is breeds. And those breeds are noticeably different, just think of cats, dogs, cows, pigs and so on. I really see no reason why this wouldn't extend to humans as well. And that the distinct groups wouldn't have some markers. Like longer than average bones.

Now, issue really is that whole race grouping is extremely murky. And not really anywhere specific enough as used in common speech. White, Black, Asian etc. are way too wide to be very useful. Even inside what we could understand as rather homogenous groups there is lot of difference between areas.

If it's trivial, why are results so variable on different ethnicity websites? And what happens when the definition of "white" changes in 30 years to unambiguously include Latinos?

(Hint : what you want is a classifier on ethnicity, and those aren't trivial either)

There’s nothing trivial about determining race in healthcare research.

Feel free to cite sources.