Research project Macroevolution and biodiversity in the Gnetales

Extant diversity is limited to less than 100 species, since long suggested to be remains of a former much more diverse clade. They seem to have had their diversity peak during a surprisingly short time in the Early Cretaceous, but microfossil data indicate that the group has endured repeated diversity peaks and crashes throughout the Mesozoic and Cenozoic. They have apparently been at the brink of extinction several times through geological history.

The Gnetales are unique in many respects and are often referred to as “odd”, difficult to understand. Pollination biology is intriguing, and comprises insect pollination as well as wind pollination, both with advanced adaptations and spectacular features. The insect-pollinated Ephedra foeminea correlates its pollination with the full moon. National Geographic and Swedish Radio produced informative material on this.
The project started 2000 and the end date for this project has not yet been determined.

The first photo below shows Ephedra foeminea (female cone with pollination drop) in its natural habitat in Greece. From Bolinder et al., Botanical Journal of the Linnean Society (2016). The second shows Cratonia cotyledon, a fossil seedling, related to Welwitschia. From Rydin et al. Proceedings of the Royal Society B (2003).