Robert Krulwich over at NPR has a very interesting bit on how, when blindfolded or deprived of external markers, we humans can’t walk in a straight line.
Try this: Put a blindfold on someone, take them to a park or a beach or a meadow and ask them to walk for as long as they can in a straight line. Then watch what happens:
I’m always fascinated with stuff like this and I look forward to someone eventually figuring out the reason why. My guess is we’re just kind of stupid that way, but I’m sure the real answer is much more revealing.