The closest evidence I've seen is pair-correlations between different people. I've read articles stating that there exists no common accepted definition of what neurological basis of intelligence is, only fairly vaguely defined concepts like "g" and debate over whether or not "g" is the most meaningful definition of intelligence.
It's pretty simple - can I measure intelligence like I measure weight or distance? If so, how accurate is a given test and how precise is it in terms being able to resolve differences in intelligence. It's not a hard question and data should be readily available like it is with any high performance scientific equipment.
If you define the "intelligence" as the ability to solve IQ test, then the answer is YES!