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Title: The evolutionary assembly of forest communities along environmental gradients: recent diversification or sorting of pre‐adapted clades?
Summary

Recent studies have demonstrated that ecological processes that shape community structure and dynamics change along environmental gradients. However, much less is known about how the emergence of the gradients themselves shape the evolution of species that underlie community assembly. In this study, we address how the creation of novel environments leads to community assembly via two nonmutually exclusive processes: immigration and ecological sorting of pre‐adapted clades (ISPC), and recent adaptive diversification (RAD). We study these processes in the context of the elevational gradient created by the uplift of the Central Andes.

We develop a novel approach and method based on the decomposition of species turnover into within‐ and among‐clade components, where clades correspond to lineages that originated before mountain uplift. Effects of ISPC and RAD can be inferred from how components of turnover change with elevation. We test our approach using data from over 500 Andean forest plots.

We found that species turnover between communities at different elevations is dominated by the replacement of clades that originated before the uplift of the Central Andes.

Our results suggest that immigration and sorting of clades pre‐adapted to montane habitats is the primary mechanism shaping tree communities across elevations.

 
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Award ID(s):
1754647 1836353
NSF-PAR ID:
10446840
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
232
Issue:
6
ISSN:
0028-646X
Format(s):
Medium: X Size: p. 2506-2519
Size(s):
["p. 2506-2519"]
Sponsoring Org:
National Science Foundation
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