Although plant reproductive structures are incredibly diverse overall, unrelated groups can show strong convergence in specific forms. Bonacorsi and Leslie use lycopsids, an ancient lineage with relatively simple reproductive biology, to test if such convergence results from performing a limited suite of functions, which leads to a reduced set of morphological solutions.
Multivariate analyses of living and fossil lycopsids (clubmosses and firmosses) reveals that the group has evolved and maintained very similar reproductive structures over their long evolutionary history, despite major changes in size, growth habit, and ecology. Similar kinds of reproductive structures are also found across plant groups with wind-dispersed pollen or spores.
Bonacorsi, N. K., & Leslie, A. B. (2018). Functional diversity and convergence in the evolution of plant reproductive structures. Annals of Botany, 123(1), 145–152. https://doi.org/10.1093/aob/mcy151