modern ears of corn differ widely from race to race in size,shape,and color,the result of thousands of years of human selection,the ear in the lower right corner is U.S.Corn Belt dent,the world's most productive corn,to the left of it is an ear of Cuzco Gigante,a Peruvian race with the world's largest kernels,Above the Cuzco ear is the tiny lady Finger Pop,or Argantine popcorn,thought to be a present-day,reliet of the early Tehuacan maize