Cahokia did not have 40,000 people in 1800 - it had that many at its peak in the 1500s. By the time French settlers reached it, a completely different group was living there, and it was pretty much uninhabited by 1800. Philadelphia surpassed 40,000 in 1800, making it the next-biggest, but they definitely didn't overlap.
Re: Rocky - As an anthropologist, I can refute that. It isn't "take my word for it" - anthropologists, like any other good scientists, need hard evidence. This guy is just jumping to conclusions based on very little data.
There are so many problems with this - first, who's saying they were better? We can do more with technology. (Re: Christine - the modern world has way more philosophers than ancient Greece, as we have more time in which to do it and a societal support system.) Also, it's very difficult to estimate time from stride, as it depends on height, and one would need a very complete archaeological record to estimate the average height of those people. Neanderthals were differently muscled, yes - they may even have been a separate species. Roman soldiers could march (they jogged, actually) really far - but people RUN in a marathon and it only takes a couple hours. And how do they know how far a spear was thrown? Who's measuring out in the wilderness? In our modern world we don't *need* to be incredibly strong and fit and powerful to survive, but that doesn't make us wimps.
In our modern world we don't *need* to be incredibly strong and fit and powerful to survive, but that doesn't make us wimps.