Chen, F.; Wang, Y.; He, J.; Chen, L.; Xue, G.; Zhao, Y.; Peng, Y.; Smith, C.; Zhang, J.; Chen, J.; et al. Molecular Mechanisms of Spawning Habits for the Adaptive Radiation of Endemic East Asian Cyprinid Fishes. Research, 2022, 2022. https://doi.org/10.34133/2022/9827986.
Chen, F.; Wang, Y.; He, J.; Chen, L.; Xue, G.; Zhao, Y.; Peng, Y.; Smith, C.; Zhang, J.; Chen, J.; et al. Molecular Mechanisms of Spawning Habits for the Adaptive Radiation of Endemic East Asian Cyprinid Fishes. Research, 2022, 2022. https://doi.org/10.34133/2022/9827986.
Chen, F.; Wang, Y.; He, J.; Chen, L.; Xue, G.; Zhao, Y.; Peng, Y.; Smith, C.; Zhang, J.; Chen, J.; et al. Molecular Mechanisms of Spawning Habits for the Adaptive Radiation of Endemic East Asian Cyprinid Fishes. Research, 2022, 2022. https://doi.org/10.34133/2022/9827986.
Chen, F.; Wang, Y.; He, J.; Chen, L.; Xue, G.; Zhao, Y.; Peng, Y.; Smith, C.; Zhang, J.; Chen, J.; et al. Molecular Mechanisms of Spawning Habits for the Adaptive Radiation of Endemic East Asian Cyprinid Fishes. Research, 2022, 2022. https://doi.org/10.34133/2022/9827986.
Abstract
The Yangtze River is cross-linked with numerous lakes within its floodplain and is a worldwide biodiversity hotspot. There is no evidence indicating when this unique river-lake system developed. The endemic East Asian cyprinid clade has evolved diverse spawning adaptations to different flow conditions. Our ancestral egg-type reconstruction showed an ancestral state of adhesive eggs and later demersal eggs origination (both stream adaptations). Semi-buoyant eggs emerged ~18 Mya as a fast-flowing river adaptation, with increased hydration via three yolk protein degradation pathways, ion transport pathways and egg envelope permeability transition pores. Adhesive eggs evolved secondarily ~14 Mya with the egg envelope increasing to four layers and an adhesive layer, along with an increase in adhesiveness via microfilament/adhesive-related protein crosslinking and enhanced glycosaminoglycan biosynthesis, improving adherence to submerged lake plants, indicating that the cross-linked river-lake system formed in the mid-Miocene. This study provides a unique biological evidence for large-scale water system evolution.
Keywords
Formation of the Yangtze river-lake system, Mid-Miocene, ancestral egg-type reconstruction, endemic cyprinids
Subject
Environmental and Earth Sciences, Atmospheric Science and Meteorology
Copyright:
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