The Sea Wasp (Ryk E. Spoor)

Also, the only really wide-spread domesticated animal the Native Americans had was the one they shared with Eurasians: The dog. All the other American domesticates were very localized, as opposed to the Old World animals that had spread far and wide through 3 continents. Any diseases that might have made the dog-human jump in the Americas, were already likely to have done so somewhere in the Old World.