Bronze Age
The land was plowed by teams of oxen pulling light unwheeled plows and grain was harvested with sickle. Wagons had solid wheels covered by leather tires kept in position by copper nails and were drawn by oxen. As many as four animals could pull a wagon at one time. The horse was domesticated in Ukraine around 4000 BC, and was in use by the Sumerians around 2000 BC.