In addition to their increased genetic variability, introgression with other tetraploid lineages, diploid progenitors, or even other species, further increases the available pool of genetic variants to polyploids. Furthermore, population genetic theory predicts both short- and long-term benefits of polyploidy and new empirical data suggests that established polyploids may act as “sponges” accumulating adaptive allelic diversity.

In line with these observations of polyploid evolutionary success, recent work documents instant physiological consequences of WGD associated with increased dehydration stress tolerance in first-generation autotetraploids. In fact, ecological modeling commonly supports patterns of adaptive niche differentiation in polyploids, with young polyploids often invading new niches and leaving their diploid progenitors behind. Despite these immediate issues some lineages nevertheless persist and thrive. However, challenges immediately following WGD, such as the maintenance of stable chromosome segregation or detrimental ecological interactions with diploid progenitors, commonly do not permit establishment of nascent polyploids. Plants are particularly rich in documented WGDs, with recent and ancient polyploidization events in all major extant lineages.

Whole genome duplication (WGD) is a dramatic mutation with long-lasting effects, yet it occurs repeatedly in all eukaryotic kingdoms. The duplication of an entire genome is no small affair.

6School of Life Sciences and Future Food Beacon, University of Nottingham, Nottingham, United Kingdom.

5Department of Botany, Faculty of Science, Charles University in Prague, Prague, Czechia.

4Department of Botany, University of Innsbruck, Innsbruck, Austria.

3Biological and Environmental Sciences, University of Stirling, Stirling, United Kingdom.

2Department of Cell and Developmental Biology, John Innes Centre, Norwich, United Kingdom.

1Institut de Biologie de l'École Normale Supérieure, Paris, France.

Pierre Baduel 1, Sian Bray 2, Mario Vallejo-Marin 3, Filip Kolář 4,5 and Levi Yant 2,6 *

Anno 2055 2018