Tropical forests in the Americas are changing too slowly to track climate change.

Understanding the capacity of forests to adapt to climate change is of pivotal importance for conservation science, yet this is still widely unknown. This knowledge gap is particularly acute in high-biodiversity tropical forests. Here, we examined how tropical forests of the Americas have shifted community trait composition in recent decades as a response to changes in climate. Based on historical trait-climate relationships, we found that, overall, the studied functional traits show shifts of less than 8% of what would be expected given the observed changes in climate. However, the recruit assemblage shows shifts of 21% relative to climate change expectation. The most diverse forests on Earth are changing in functional trait composition but at a rate that is fundamentally insufficient to track climate change. Species are expected to shift their ranges as the climate changes, but shifts may not occur fast enough, especially for immobile species such as plants. Two papers in this issue assess the degree to which plant species are tracking climate change in the American tropics, where data availability has constrained inference. Ramírez-Barahona . show that in Mesoamerican cloud forests, climate change and deforestation together have led to a mean upward shift in species ranges since 1979, mainly due to contracting lower range edges. In tropical forests across the Americas, Aguirre-Gutiérrez . found that tree traits are not shifting fast enough to track climate change based on trait-climate relationships, with smaller shifts in montane forests. —Bianca Lopez

Project(s)

Priority 4: Accelerated Taxonomy

Funder

Funder name	Awards
Natural Environment Research Council, United States	NE/T011084/1 - NERC Pushing the Frontiers (NE/Z504191/1) - NE/D014174/1 - NE/J022616/1 - ECOFOR (NE/K016385/1) - NE/K016431/1 - NE/S01084X/1
University of Oxford, United Kingdom	John Fell Fund (grant 10667)
European Research Council, European Union	Advanced Investigator Award (GEM-TRAIT grant 321131)
Seventh Framework Programme, European Union	Grant FP7/2007–2013
National Science Foundation, United States	Long-Term Research in Environmental Biology program (LTREB grant DEB 1754647) - Grant no. 2225078 - Grant no. 2225076
Gordon and Betty Moore Foundation, United States	Andes–Amazon Program
Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil	PQ1 grants 311027/2019-9 - 303492/2022-8 - Long-Term Ecological Research Program (PELD), process 441244/2016–5 - Process 441572/2020-0 - PELD process 403710/2012–0 - PELD project 441244/2016-5 - PELD project 441572/2020-0 - PDJ process no. 152806/2024-5 - Process 2003/12595-7 - Process 2012/51509-8 - Process 2012/51872-5, within the BIOTA/FAPESP Program—The Biodiversity Virtual Institute
Fundação de Amparo à Pesquisa do Estado de Mato Grosso, Brazil	Project ReFlor, processes 589267/2016 - PELD/FAPEMAT 0346321/2021
Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
Universidad Nacional de Córdoba, Argentina
Red Federal de Alto Impacto CONATURAR, Argentina	Grant 2023-102072649-APN-MCT
Oxford Martin School, University of Oxford, United States
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brazil	Project 136277/2017-0 - Finance Code 001
Frank Jackson Foundation, United Kingdom
Leverhulme Trust, United Kingdom
Comisión Nacional Forestal, Mexico
Consejo de Cíencia y Tecnología del Estado de Durango, Mxico