Are most Brazilians descendants of recent immigrants or 'Old Brazilians' of colonial stock (Portuguese, African, Native American)?

Answer 1

That is not an easy question. Brazilians in general are very mixed.

We have both situations and in great diversity. About half of the population consider themselves black. And there are no recent migration of Africans to Brazil, therefore all of those people have to have "old Brazilian" blood. However Brazil's "black" is much more of a mixture than here in US. That means that they can also be descendants of more recent migrations, as from Europeans in the 19th century, as when doing a genetic background they might have way less than 50% of African origin, but are still black because of the dominant genetic features.

The other great majority of the population is caucasian (47.7%). That part of the population, even though very diverse and having people of older Brazilian families (also having African descendants), is where it is easier to identify more recent migrations. Being more recent you can see the elderly speaking of how their parents/grand parents talked about "the old country". Also there are other ethnicities such as arabic (that fall in the caucasian in Brazil's demographics) and other Asian, that are all more recent migrations.

So most of Brazilians are a mix of both situations, and we are unable to determine which percentage of the populations come from "newer" or "older" lineages.