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Updated: Jul 4, 2025
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
973
Modelling evolutionary tempo and mode using formal morphological spaces and Markov chain principles
Gabriela Fontanarrosa1, Virginia Abdala1,2, Daniel Andrés Dos Santos1,2
1Instituto de Biodiversidad Neotropical, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Tucumán, Yerba Buena, Tucumán, Argentina.
Journal of Evolutionary Biology
|January 29, 2024
Summary
Evolutionary analysis of Lepidosaurian phalangeal formulae reveals a trend toward reduced bone counts. Changes primarily occur between similar forms, though occasional large shifts also happen.
Area of Science:
- Theoretical biology
- Evolutionary biology
- Paleontology
Background:
- Evolutionary tempo and mode address core biological debates like gradualism and convergence.
- Phalangeal formulae (PFs) are discrete characters valuable for studying evolutionary patterns.
Purpose of the Study:
- To explore the evolutionary tempo and mode of Lepidosaurian phalangeal formulae (PFs).
- To quantify morphological change frequencies along evolutionary trajectories using an integrative approach.
Main Methods:
- Utilized a dataset of PFs from 649 taxa, including fossils.
- Integrated phenetic and phylogenetic data to reconstruct evolutionary dynamics.
- Constructed flow networks to analyze transitions between unique phenotypic conditions.
Main Results:
- Identified a significant trend towards reduction in phalangeal count during Lepidosaurian evolution.
- Observed that evolutionary changes predominantly occur between morphologically similar PFs.
- Documented occasional, though less frequent, transitions between distant formulae ('jumps').
Conclusions:
- Results support a pluralistic view of evolution, encompassing stasis, gradualism, and saltationism.
- Demonstrated the prevalence of different evolutionary modes for phalangeal formula evolution.
- Highlighted the utility of PFs in understanding evolutionary dynamics.
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