Did humans really invented the wheel? It seems like Mother Nature had us beat: salamanders and caterpillars have been "rolling" like a wheel long before humans invented it.
A lot of Bacteria use their flagellum to move, and it is a whip. but the base of it functions as a simple wheel, or at least a rotating system with an axle.
If I remember correctly I believe that there is also a type of desert spider that cartwheels, well, like a wheel down a sand dune to avoid being eaten by lizards.
A lot of Bacteria use their flagellum to move, and it is a whip. but the base of it functions as a simple wheel, or at least a rotating system with an axle.
http://en.wikipedia.org/wiki/Flagella#Bacterial_flagellum