Incas
A large Spanish speaking population.
Mexico
Oklahoma has the largest Native American population of any state; at 8.9% (2010 Census Statistic).
'What was the Spanish Empire?' At its greatest extent it had much of South America, quite a large area of Central and North America, many Pacific islands and quite a large area of Europe.
Brazil
The population for North America and South American were different because they both stayed on there own side. Back in time places did not mix.
Brazil has almost the same population as all other countries in South America put together.
Around 80% of the population of South America lives in urban areas. Major cities in South America include Sao Paulo, Buenos Aires, and Lima, which have large urban populations.
South America is 6,890,000 square miles
South America is 17840000 kilometers.
In North America: Canada Haiti In South America: French Guiana (there is also a large French speaking population in the United States).
The population of South Dakota's At-large congressional district is 754,854.
The United States is 3,794,000 square miles large, and South America is 6,888,000 square miles large. The US is 55.08% of the size of South America. South America is 1.815 times the size of the US. So ultimately to answer your question, No, the US is not twice as large as South America but is almost half the size (3,444,000 mi2).
large areas of both south america and africa are in the tropics.
I believe most of the population of South America is located at or near the coastal regions (seacoast primarily) in larger cities and towns, some populations live along large rivers and in high mountains, but these are not the primary population concentrations of South America. I believe most tribal populations will contribute to the strong tendency of statistical migration to the coastal cities, and will not grow to large sizes in the interior regions, in the present era and foreseeable future.
No, unfortunately they are extinct, mainly due to the land bridge between North and South America, which brought large cats into South America and the predatory competition was too much for an already limited population.