Howdidzebrasgettheirstripes?It’shardtogetablack-and-whi...
問題詳情：Howdidzebrasgettheirstripes?It’shardtogetablack-and-whiteanswer.Somescientistssaythestripesareaformofcamouflage(偽裝)，___61___ protectszebrasfromhungrylions.Otherssaythey’rekeytozebras’ma...