“I can easily recognize people descended from non-European ancestors that have been here 400 years.”
Which still does nothing to demonstrate what you were trying to demonstrate with this example, for reasons I have already explained (it’s an apples to oranges comparison, and you can’t control for other variables).
What was true for 2350BC to 1950BC should be true for 1614AD to 2014AD, and there is no evidence that our temperate climate has changed anyone to a great degree who descend from tropical climates.