Complex sentence: Among the World's cultivated species this group has some of the most complex genetic histories, epitomized by bread wheat, which contains the genomes of three species, only one of them originally a wheat "Triticum" species.
Split into simpler sentences: Among the world's cultivated species this tribe has some of the most complex genetic histories. An example is bread wheat, which contains the genomes of three species, only one of them originally a wheat "Triticum" species.