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TheEconomistFebruary25th
Leaders
Diamondsandmarriage
Agirl’snewbestfriend
Thediamondengagementringmaynothaveafutureasasymbolofcourtship.Whatcouldreplaceit?
PEACOCKSstrut;bowerbirdsbuildlovenests;spidersgift-wrapfliesinsilk.SuchcourtshipritualsplayanimportantroleinwhatCharlesDarwincalledsexualselection:whenthefemaleofaspeciesbearsmostofthecostsofreproduction,malesuseextravagantdisplaysandgiftstodemonstratetheir“reproductivefitness”andfemaleschoosebetweenthem.Forhumanmales,shardsofacrystallineformofcarbonoftenfeature.Adiamondengagementringsignalsaman’staste,wealthand
