Evolutionary psychologists believe that the ability to preserve wealth gave modern humans the decisive edge in evolutionary competition with other humans. Nick Szabo included an interesting anecdote in his essay “Shelling Out: The Origins of Money.” When Homo sapiens sapiens displaced Homo neanderthalensis in Europe roughly 35,000 years ago, a population explosion followed. It’s difficult to explain why, because the newcomers, H. s. sapiens had similar-sized brains, weaker bones and smaller muscles than the Neanderthals. The biggest difference may have been wealth transfers made more effective or even possible by collectibles. H. s. sapiens took pleasure from collecting shells, making jewelry out of them, showing them off and trading them. Neanderthals did not.