Phylogenetic constraints, conservatism, and convergence shape three-dimensional variation in flower morphology of a tropical orchid radiation

Autor(en)

Silvia Artuso, Alexander Gamisch, Yannick M. Staedler, Jürg Schönenberger, Hans Peter Comes

Abstrakt

SUMMARY Despite advances in phylogenetic comparative methods, challenges remain to distinguish between various macroevolutionary patterns of phenotypic variation (e.g., conservatism, convergence) and to infer their underlying proximate (genetic, developmental) or ultimate (selective versus neutral) causes. Furthermore, especially for complex morphological structures, little is known about the extent to which rates of trait and species diversification are coupled. To address these issues, we explored the modes and temporal dynamics of high-dimensional (3D) flower shape evolution in Malagasy Bulbophyllum orchids (crown age: c. 12.7?Ma), representing the largest dataset of its kind in an angiosperm lineage (111 spp.). We identified three major flower shape types, which likely evolved under the influence of pollinator-mediated selection around a ?primary? (lineage-wide) adaptive optimum over time. Moreover, we uncovered multiple instances of convergence and, in a recently derived subclade, a notable trend of shape ?reversion? towards an earlier rather than more recent ancestral state. We conclude that the evolution of 3D flower shapes in orchids can be strongly influenced by phylogenetic constraint and conservatism while having no significant influence on species diversification. Hence, 3D flower shape (as potential pre-zygotic reproductive isolation trait) may play less a role in explaining the diversification dynamics of orchids than generally assumed.

Organisation(en)

Department für Botanik und Biodiversitätsforschung

Externe Organisation(en)

Paris-Lodron Universität Salzburg

Journal

The Plant Journal

Band

126

Anzahl der Seiten

16

ISSN

0960-7412

DOI

https://doi.org/10.1111/tpj.70883

Publikationsdatum

2026

Peer-reviewed

Ja

ÖFOS 2012

106008 Botanik, 106042 Systematische Botanik, 106012 Evolutionsforschung

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/3441e4fd-32b0-4dc7-ad54-6262f3ee63b7