Paleopolyploidy

Paleopolyploidy is the condition resulting from a genome duplication that occurred at least several million years ago, either doubling a single species' own genome or combining the genomes of two different species. Over evolutionary time most paleopolyploid lineages lose their polyploid status through a process called diploidization and come to be treated as ordinary diploid organisms. Baker's yeast and the plant Arabidopsis thaliana are cited as lineages that carry this kind of ancient duplication. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/