The organisms having more than two sets of chromosomes (3n, 4n, 5n, 6n) are called polyploids. The polyploids are common among plants and rarely found in animals. . Polyploidy is means of rapid speciation. Polyploidy often leads to uneven distribution of chromoses among the daughter cells due to large number of chromosomes thus leading to genetic variation and occurence of new species. Polyploidy also results in a large number of combinations of genes paving way for speciation. The different types of wheat varieties have evolved through polyploidy. Original number of chromosomes in wheat (Triticum moncoccum) is 2N = 14. By polyploidy hexaploid varieties of wheat (Triticum aestivum) have been obtained (6N = 42).