Precipitation is the main axis of tropical phylogenetic turnover across space and time

Authors: RINGELBERG, JENS - University Of Zurich; KOENEN, ERIK - University Of Zurich; SAUTER, BENJAMIN - University Of Zurich; AEBLI, ANAHITA - University Of Zurich; RANDO, JULIANA - Federal University Of Bahia Reconcavo; IGANCI, JOAO - Federal University Of Pelotas; PG DE QUEIROZ, LUCIANO - Universidade Feira De Santana; MURPHY, DANIEL - Royal Botanical Gardens; GAUDEUL, MYRIAM - Institut Curie; BRUNEAU, ANNE - Universite De Montreal; LUCKOW, MELISSA - Cornell University; LEWIS, GWILYM - Royal Botanical Gardens; MILLER, JOSEPH - Global Biodiversity Information Facility (GBIF); SIMON, MARCELO - Embrapa; JORDAO, LUCAS - Instituto De Pesquisa E Reabilitacao De Animais Marinhos; MORALES, MATIAS - Instituto Nacional De Tecnologia Agropecuaria; BAILEY, DONOVAN - Consejo Nacional De Investigaciones Científicas Y Técnicas(CONICET); Nageswara-Rao, Madhugiri - Rao; LOISEAU, ORIANE - University Of Edinburgh; PENNINGTON, TOBY - University Of Exeter; DEXTER, KYLE - Royal Botanical Gardens; ZIMMERMAN, KIKLAUS - University Of Zurich; HUGHES, COLIN - Swiss Federal Institute

Submitted to: Science Advances
Publication Type: Popular Publication
Publication Acceptance Date: 1/17/2023
Publication Date: 2/17/2023
Citation: Ringelberg, J.J., Koenen, E.J., Sauter, B., Aebli, A., Rando, J.G., Iganci, J.R., Pg De Queiroz, L., Murphy, D.J., Gaudeul, M., Bruneau, A., Luckow, M., Lewis, G.P., Miller, J.T., Simon, M.F., Jordao, L.S., Morales, M., Bailey, D.C., Nageswara Rao, M., Loiseau, O., Pennington, T.R., Dexter, K.G., Zimmerman, K.E., Hughes, C.E. 2023. Precipitation is the main axis of tropical phylogenetic turnover across space and time. Science Advances. 9. Article eade4954.

Interpretive Summary: Understanding the environmental and historical factors that shape the global distribution of evolutionary lineages has been a central question in biogeography and macroevolution. To understand the contemporary spatial structure of diversity, turnover across space and time need to be considered together, but this is rarely achieved in empirical studies. We investigated phylogenetic turnover through the last 45 million years across the global lowland tropics using the Mimosoid clade of legumes involving 89 of 90 mimosoid genera and 420 species (eg., Acasia, Mimoseae, Leucaena etc). Our results show that the precipitation gradient from arid deserts to hyper-wet rainforests dictates turnover of lineages within continents across the lowland tropics. Overall similarity between rainfall patterns and phyloregions provided independent evidence that precipitation is the main driver of evolutionary turnover within the tropics for mimosoid legumes. The present study helps in global understanding of heterogeneous opportunities provided by global climate change, ultimately leading to long distance dispersal and current pantropical dominance of mimosoid legumes.

Technical Abstract: Despite advances in global mapping of species diversity, the environmental and historical factors and processes shaping the spatial and temporal turnover of evolutionary lineages remain poorly understood. Furthermore, the extent of phylogenetic niche conservatism across the Tree of Life is disputed. Using phylogenomic and geographic data for a species-rich, pantropical clade of plants – mimosoid legumes, we show that the precipitation gradient from arid deserts to hyper-wet rainforests dictates turnover of lineages within continents across the lowland tropics. Turnover is profoundly shaped by phylogenetic niche conservatism with 95% of speciation occurring within a precipitation niche and turnover boundaries corresponding to isohyets. Our results show similar patterns shaped by similar processes on different continents, implying that evolution and dispersal across continents follows universal processes and drivers.