Final answer:
The population of South America was diverse and sizeable around 1500, with estimates of 65 million people. Over time, demographic shifts occurred, and today, significant numbers of people of European, Asian, African, and Amerindian descent collectively form the population. Various estimates of population numbers exist, with lower populations likely after European contact.
Step-by-step explanation:
Based on the provided legend and information, several conclusions can be drawn about the population of South America. Prior to European contact, the Americas, including South America, had a population that rivaled that of Europe and Africa. Notably, the population of South America was approximately 65 million around the year 1500. Over the centuries, South America experienced significant demographic changes, with a rich tapestry of cultural diversity, including Amerindians, individuals of European, Asian, and African descent, and populations with mixed ethnic backgrounds.
Understanding the cultural geography of South America is key to recognizing its human development patterns. The populations in South America's countries are immensely diverse. For instance, countries like Argentina and Uruguay have majorities of people of European descent, while others like Peru and Bolivia primarily consist of Amerindian populations. Meanwhile, Guyana, Suriname, and areas along Brazil's eastern coast have significant populations of Asian and African descent, respectively. The hypothesis about why people in the Western Hemisphere got ill during European contact, whereas it wasn't the other way around, relates to the lack of prior exposure to Old World diseases among the indigenous populations, which rendered them more susceptible.
Regarding the historical estimates of the indigenous population, through various time periods, there have been disparities in population estimates, with earlier historians often underestimating the numbers. As for the period witnessing the lowest population of Indigenous people, it would likely be after substantial contact with Europeans due to disease, conflict, and other factors.