Abstract Detail

Modeling the processes that mediate speciation and extinction rates across plants

Hernández-Gutiérrez, Rebeca [1], von Balthazar, Maria [2], Magallon, Susana [3].

Linking dynamic processes: species diversification and evolution of floral integrated phenotype in Malvaceae s.l.

Species diversification may be promoted by the evolution of intrinsic traits, enabling organisms to interact with environment or with coexisting biota in different ways. In some cases, these traits may represent key innovations that trigger increases in diversification, and in others, the diversification is influenced by the rate at which a trait or a combination of traits evolve, rather than the acquisition of the trait itself. For example, flowers comprise a functional unity of numerous integrated traits that play a central role in reproductive isolation, which may influence species diversification. Floral diversity is outstanding, particularly in some groups. One such a group is Malvaceae s.l., in which flowers are characterized by a wide variety of morphologies, whorl organization, multiplication of organs, different degrees of union and fusion of organs, and variation in structural and functional traits. The variation in the androecium is especially remarkable. Malvaceae is the largest family in Malvales and is among the clades with the highest diversification rate among angiosperms. Its great species-richness and morphological floral diversity have been previously noted, although the processes underlying such diversity have not been investigated. Within Malvaceae, some groups display different combinations of floral character states, but key traits have not been detected. The aim of this research is to test whether floral morphological evolutionary rate is correlated with diversification rate. To examine this, we assembled a morphological data matrix comprising 66 floral characters of 97 species, using an exemplar approach. With a sample of phylogenetic dated trees, we estimated diversification rate through time, and reconstructed the ancestral state of each character individually. We used a method for character amalgamation, in which characters corresponding to anatomical or developmental sectors are hierarchically grouped, such that ancestral state and morphological evolutionary rate can be estimated in an integrated, biological framework. With the amalgamation of all floral traits, we obtained the evolutionary rate of the entire floral phenotype. We then tested whether floral evolutionary rate is correlated with diversification rate of Malvaceae. Our results point to a more integrative hypothesis of the processes and mechanisms underlying the highly dynamic evolution of this important group of plants.

1 - Universidad Nacional Autonoma de Mexico, Posgrado en Ciencias Biologicas, Instituto de Biologia, 3er Circuito de Ciudad Universitaria, Mexico City, 04510, Mexico
2 - Department Of Botany And Biodiversity Research, Division Of Systematic And Evolutionary Botany, Rennweg 14, Vienna, 9, A-1030, Austria
3 - Universidad Nacional Autonoma De Mexico, Instituto De Biologia, 3er Circuito De Ciudad Universitaria, Del. Coyoacan, A.p. 70-233, Mexico City, Mexico D.F., DIF, 04510, Mexico

Keywords:
diversification
Trait evolution
macroevolution
Malvaceae.

Presentation Type: Colloquium Presentations
Session: C01, Modeling the processes that mediate speciation and extinction rates across plants
Location: /
Date: Monday, July 19th, 2021
Time: 11:15 AM(EDT)
Number: C01005
Abstract ID:323
Candidate for Awards:None