 About half of all polyploids are thought to be the result of autopolyploidy, although many factors make this proportion hard to estimate.Allopolyploids or amphipolyploids or heteropolyploids are polyploids with chromosomes derived from two or more diverged taxa.As in autopolyploidy, this primarily occurs through the fusion of unreduced (2"n") gametes, which can take place before or after hybridization.