Jared Diamond — American Author born on September 10, 1937,

Jared Mason Diamond is an American scientist and author best known for his popular science books The Third Chimpanzee, Guns, Germs, and Steel, Collapse and The World Until Yesterday. Originally trained in physiology, Diamond is known for drawing from a variety of fields, including anthropology, ecology, geography and evolutionary biology. As of 2013, he is Professor of Geography at the University of California, Los Angeles... (wikipedia)

AIDS and malaria and TB are national security issues. A worldwide program to get a start on dealing with these issues would cost about $25 billion... It's, what, a few months in Iraq.
Technology has to be invented or adopted.
Introspection and preserved writings give us far more insight into the ways of past humans than we have into the ways of past dinosaurs. For that reason, I'm optimistic that we can eventually arrive at convincing explanations for these broadest patterns of human history.
All human societies go through fads in which they temporarily either adopt practices of little use or else abandon practices of considerable use.
Measles and TB evolved from diseases of our cattle, influenza from a disease of pigs, and smallpox possibly from a disease of camels. The Americas had very few native domesticated animal species from which humans could acquire such diseases.