Man is the animal that intends to shoot himself out into interplanetary space, after having given up on the problem of an efficient way to get himself five miles to work and back each day. ↗
Eurasia ended up with the most domesticated animal species in part because it's the world's largest land mass and offered the most wild species to begin with. ↗
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. ↗