Phylogeny, historical biogeography and niche evolution in neotropical Marcgraviaceae – a model case for the study of rapid morphological diversification and speciation through flower-pollinator interactions

• Applicants: Dr. Stefan Dressler (†); Professor Dr. Georg Zizka
• Subject Area: Evolution and Systematics of Plants and Fungi
• Term: from 2018 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 417790428

The Marcgraviaceae are a neotropical plant family of mostly climbing woody habit (132 species), whose distribution reaches from southern Mexico over the Caribbean islands to Bolivia and southern Brazil. Habitats are rainforests and cloud forests, and to a lesser extent the Cerrados of Brazil. According to current knowledge, a rapid morphological diversification and species formation has taken place on the basis of flower-pollinator interactions. Despite the very low genetic variability found so far, unique, spectacular inflorescences have developed in the family in adaptation to a large variety of pollinators from all large pollinator groups. The creation of a comprehensive molecular phylogeny serves as a basis for understanding the temporal and spatial pattern of this rapid diversification.Occurring in 6 of the 8 biodiversity hotspots on the American continent, this family is particularly suited to study the history of hotspot formation and their drivers. Extraordinarily extensive and diverse preliminary work is available, which will enable an evaluation of the molecular data in different, current directions in a comparatively short time. The following questions are to be adressed:(1) Where and when do the Marcgraviaceae originate and what routes have they taken? (2) How have different morphological features evolved and how has this led to the colonisation of new habitats or the development of new pollinator spectra? (3) What influence did morphological innovations have on diversification rates? (4) Are diversifications within Marcgraviaceae linked to geological or climatic changes (e.g. Andean uplift, closure of the isthmus of Panama)?(5) How has niche evolution or conservatism influenced the evolution and distribution history of the individual taxa of Marcgraviaceae?

• DFG Programme: Research Grants