Humans have collected crystals for nearly 800,000 years, despite their having no obvious practical purpose. Experiments led by Professor Juan Manuel García-Ruiz may now help explain why. As reported by IFLScience, chimpanzees strongly preferred a quartz “monolith” over an ordinary rock and quickly selected crystals from piles of pebbles, suggesting that transparency and geometric form have appealed to primates since long before the emergence of modern humans.
