J Syst Evol ›› 2025, Vol. 63 ›› Issue (1): 115-133.DOI: 10.1111/jse.13145

• Research Article • Previous Articles     Next Articles

Multimodes of floral disparity versus species diversity in adaptive radiation of Petrocodon (Gesneriaceae) upon Qinghai–Tibet Plateau uplift

Peng‐Wei Li1,2,3†, Jing Liu1,2,4†, Ming‐Tao Liu1,5†, Bo Pan3, Yang Dong1,2,4, and Yin‐Zheng Wang1,2,4*   

  1. 1State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
    3Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Institute of Botany, Guangxi Zhuangzu Autonomous Region and the Chinese Academy of Sciences, Guilin 541006, China
    4China National Botanical Garden, Beijing 100093, China
    5Qiannan Medical College for Nationalities, Duyun 558000, China

    These authors contributed equally to this work.
    *Author for correspondence. E‐mail: wangyz@ibcas.ac.cn
  • Received:2024-01-15 Accepted:2024-10-14 Online:2024-12-15 Published:2025-01-01
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (31470333, 32170228, 32460057), Guangxi Natural Science Youth Found Program (2023GXNSFBA026113), and the Research Fund of Qiannan Medical College for Nationalities (QNYZ202442).

Abstract: Adaptive radiation is usually triggered by great in situ or ex situ environmental changes. How an adaptive radiation occurs on lands and how species richness relates to morphodisparity have been a major focus of evolutionary biology. Petrocodon, diversified in the southeastern Qinghai–Tibet Plateau (QTP), represents an ideal model to address these questions. To elucidate the dynamics of adaptive radiation of Petrocodon, we took an integrative approach, including phylogenetic, dating, disparity versus diversity, pollination, and gene expression analyses. Petrocodon with six clades has experienced radiation following the QTP uplift. Multiple modes of floral morphodisparity versus species diversity occur in the radiation process that are directly linked to their colonizing new environments and diversification with geographic expansion. Pollination and gene expression analyses suggest that accelerated emergence of de novo mutations might be relevant to the multiplex floral disparity and pollinator shifts in Petrocodon. For the first time in plants, we report that decreased genetic constraints on floral architecture triggered by QTP uplift might have generated abundant floral morphological variants, which were further targeted by selection for ecological divergence. The multiple modes of floral disparity versus species diversity may be attributed to accelerated mutations in colonizing new environments and repeated modifications of the already evolved traits in subsequent diversification and geographic expansion in Petrocodon. Our findings shed novel light on the interplay of ecological, developmental and evolutionary dynamics of disparity versus diversity in relation to trajectory changes of floral architecture in responses to environmental disturbance in a terrestrial plant group.

Key words: adaptive radiation, disparity, diversity, floral morphology, genetic constraint, Qinghai–Tibet Plateau (QTP) uplift.