Australia is the most isolated continent.

Why did human development proceed at such different rates on different continents for the last 13,000 years?

Why is it that you white people developed so much cargo and brought it to New Guinea, but we black people had little cargo of our own?

In much of the rest of the world, rich people live in gated communities and drink bottled water. That's increasingly the case in Los Angeles where I come from. So that wealthy people in much of the world are insulated from the consequences of their actions.

In the latter case it is often government that organizes the conquest, and religion that justifies it.

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.

Science is often misrepresented as "the body of knowledge acquired by performing replicated controlled experiments in the laboratory." Actually, science is something broader: the acquisition of reliable knowledge about the world.