Format: ORAL

Pinilla Vargas, Maria, Vsquez, Diana2, Diazgranados, Mauricio3, Kolr, Filip,2, Schmickl, Roswitha1,2, Kandziora, Martha

1 Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic 2 Institute of Botany, The Czech Academy of Sciences, Pruhonice, Czech Republic 3 The New York Botanical Garden, NY 10458, USA

Climate change-induced range shifts have been documented extensively in temperate mountains, but the response of tropical alpine species remains understudied. This study aims to address this knowledge gap by focusing on the tropical alpine ecosystem of the Andes while exploring and comparing the responses of four Asteraceae plant lineages to past and future climatic changes. Using curated herbarium-backed occurrence data, we constructed species distribution models (SDMs) based on paleoenvironmental reconstructions and future climate predictions for 113 species from four monophyletic lineages and evaluated their predicted elevation changes, suitable habitat sizes and temperature ranges. We expected that habitat ranges were larger during the Last Glacial Maximum (LGM) and that they would shrink in the future, followed by species elevation shifts. Contrary to expectations, we did not observe a generalized downward shift in elevation during the LGM, and while some lineages had larger ranges in the past, this was not a general trend. Furthermore, we observed differential species responses to climate change, with species occupying broader temperature ranges having higher habitat stability over time. We speculate that the Andes complex topography, with high altitude plateaus, might be responsible for the observed patterns, distinguishing it from other tropical alpine ecosystems and highlighting the importance of considering regional and lineage-specific dynamics in understanding the impacts of climate change on habitat suitability.