Plants tend to be polyployd[1], sometimes to a rather ridiculous amount. 6x or 8x (or more) full copies of the genome is common, compared to the two copies ("di

Plants tend to be polyployd[1], sometimes to a rather ridiculous amount. 6x or 8x (or more) full copies of the genome is common, compared to the two copies ("dipooid") in most animals. This has been going on for a long time[2], so some of the older duplicate copies separated over time leaving "near duplicates" in the genome that now serve new purposes. Maintaining these "extra copies" of the genome costs energy (lowering survivability), but you get something very loosely like RAID mirroring allowing the genome to survive more errors. Having more than a single backup copy also allows a single plant species to have a lot more variation, as alternative genotypes can be saved across generations in the "backup copies". [1] http://en.wikipedia.org/wiki/Polyploid http://en.wikipedia.org/wiki/Polyploid [2] http://en.wikipedia.org/wiki/Paleopolyploidy http://en.wikipedia.org/wiki/Paleopolyploidy