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  • Featured in Physics
  • Open Access

Volatile But Persistent Coexistence of Self-Compatibility and Self-Incompatibility in Plants

Amit Jangid1, Ohad Noy Feldheim2, and Tamar Friedlander1,*

  • *Contact author: tamar.friedlander@mail.huji.ac.il
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PRX Life 4, 043005 – Published 26 October, 2026

DOI: https://doi.org/10.1103/lc75-8bf3

Abstract

Plants employ diverse mating strategies, including self- and cross-fertilization or their combination. Despite the ubiquity of mixed mating—the use of both self- and cross-fertilization within the same population—its evolutionary origins and dynamic stability remain elusive. Here, we study self-incompatibility, in which self-fertilization is disabled by molecular recognition and enabled when mutations disrupt this recognition. Using population-level stochastic simulations, we model the effects of two main parameters on the prevailing mating mode: promiscuity of molecular recognition and inbreeding depression, which penalizes self-compatibility. We reveal a phase diagram with three phases: complete self-incompatibility, complete self-compatibility, and a mixture combining both. The mixed phase exhibits newly described vigorous, nondecaying fluctuations in the proportions of individuals occupying either mating mode. Pollen limitation extends the parameter range over which complete self-incompatibility is favored, contrary to the commonly held view. This study offers new insight into the evolutionary dynamics of plant reproductive systems.

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Physics Subject Headings (PhySH)

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Promiscuity Opens Paths for Coevolution

Published 26 October, 2026

Molecular “locks” that fit many “keys” may allow different plant mating strategies to coexist within a population of a single plant species.

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PRX Life 4, 043005– Published 26 October, 2026
  • Received 1 December 2025
  • Accepted 14 August 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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