[Randallw]

The government channel here in Australia is showing all the Dr Who episodes from the beginning. I expect it's going to take them a few years to get through them all. Currently they are up to the second doctor and the Ice warriors of Mars have appeared. I was just thinking yesterday that maybe the Tardis travels to alternate futures as well. That would explain why human ships and technology are different each time he goes to the future. The timeline he is in now has matter transporters.