Paleopolyploidization events lead to massive cellular changes, including doubling of the genetic material, changes in gene expression and increased cell size.
Gene loss during diploidization is not completely random, but heavily selected. On the other hand, individual genes are not duplicated.
Other examples include the sequenced eudicot genomes of apple, soybean, tomato, cotton, etc.
Compared with plants, paleopolyploidy is much rarer in the animal kingdom.
Evidence suggests that baker's yeast (Saccharomyces cerevisiae), which has a compact genome, experienced polyploidization during its evolutionary history.