Diversification of Adesmia DC. and the role of the Andes in shaping morphology and biogeography on the evolution of plants

• Grant number: 23/11622-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): January 01, 2024
• Effective date (End): January 31, 2026
• Field of knowledge: Biological Sciences - Botany - Plant Taxonomy
• Principal Investigator: Ana Paula Fortuna Perez
• Grantee: Thiago Cobra e Monteiro
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Abstract: The Andean mountains exerted an important role in the formation of the Western South American Dry Diagonal (wSADD), which comprehends the Peruvian and Atacama deserts, Puna, the Monte desert, and the Patagonian steppes. However, little is known about how geological-climatic processes affected the distribution of species in the wSADD and adjacent environments. There is urgency in conducting historical biogeographical research on the wSADD based on dated phylogenies, considering today's fast climatic changes and the habitat fragmentation along the wSADD. The Adesmia genus (206 spp.) stands out as a model group for understanding biogeographical patterns of the wSADD because of its abundance through all wSADD. The genus is currently subdivided into two paraphyletic subgenera: A. subg. Adesmia (unarmed species) e A. subg. Acanthadesmia (armed species). The evolution of spinescent inflorescences at least two different times in Adesmia casts doubt on each key factor triggered spinescence: aridity or the advance of herbivorous mammalian lineages. Therefore, we will conduct the largest-sampled phylogenetic study of Adesmia (168/206 spp.). Maximum likelihood phylogenetic trees allied with data on species distribution, morphology, floral and inflorescence ontogeny, and ecology, will be applied to elucidate biogeographical patterns and the role of Andean mountains on the evolution and distribution of living beings native to the wSADD. A Dispersion-Extinction-Cladogenesis model will be implemented to infer ancestral biogeographical areas. We will test if functional traits - spinescence, pod appendages, and flower and leaf size - were essential to the species' occupancy and survival in arid environments. The data generated will also help predict species distribution on a hotter and drier planet. A new infrageneric classification for Adesmia will be proposed, as well as a taxonomic synopsis of Adesmia subg. Adesmia of Chile, which was last treated 55 years ago.