The concept of "clean coal" is a "dirty lie, " added environmental activist Robert F.

CNN: Washington protesters push 'clean energy,' protest coal use

One difference, according to a 2002 University of Massachusetts study conducted by psychologist Robert Feldman: Women are more likely to lie to make other people feel good, while men tend to lie to make themselves look better.

FORBES: How To Catch A Liar

Among the dunes, Robert has built his own small memorial, and segments of the ship's hull still lie partly buried in the sand, like an excavated dinosaur skeleton.

BBC: The perfect trip: South Africa