ANCIENT GENE RECRUITMENT. “One prediction that can be made from the antithetic theory is that the evolution of the sporophyte involved the recruitment of ancient genes and regulatory networks from the pre-existing gametophyte generation; these networks would then diversify and promote morphological diversification in the sporophyte generation.” Supported by transcriptomic studies.
http://rstb.royalsocietypublishing.org/content/367/1588/508.short