[Fraxinus]

I expect that Mayans did use wheels, just not on carts. The problem is that there are no draft animals that the Mayans had access to for which a wheeled cart carried more than packs. Prior to the development of roller and ball bearings any increase in load afforded by a wheeled cart pulled by humans was consumed by the friction of the wheel bearings.

I would expect that the Mayans did use small wheels to help them build their cities, better known as pulleys.

[Mr Rogers]

If you need to move 200 lbs, something with wheels - including friction - is possible. On one's back? Not likely, particularly if the object is irregular and hard. A large dog can pull a cart.

I suspect a better explanation is we sit on the shoulders of giants and think we owe our view entirely to ourselves. We've had wheels for moving loads for so many thousands of years we cannot conceive of anyone NOT making the connection...but in the New World, it seems no one did.

[Harmless Teddy Bear]

They used sleds. Which was part of the reason for the roads.