What early trade disadvantage did pre-columbian civilizations such as the maya, aztec, and inca have?

One disadvantage of Pre-Columbian civilisations is that they had no animals that could be used to carry things - such as donkeys or horses, so the goods could not be transported as well as in the Old World - those animals simply did not evolve in America or disappeared by that time. People often had to transport the goods they wanted to sell on their backs.

White dwarf is very hot, but also very small and that is why it may appear dim.