What is the best description of Australia's Aboriginal population today in comparison to what it was like pre-European colonization?

i don't get what you mean

explanation:

it's the under parts of the car

an informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.