Abstract
Understanding how diversity evolves and is maintained is critical to predicting the future trajectories of ecosystems under climate change; however, our understanding of these processes is limited in marine systems. Corals, which engineer reef ecosystems, are critically threatened by climate change, and global efforts are underway to conserve and restore populations as attempts to mitigate ocean warming continue. Recently, sequencing efforts have uncovered widespread undescribed coral diversity, including ‘cryptic lineages’—genetically distinct but morphologically similar coral taxa. Such cryptic lineages have been identified in at least 24 coral genera spanning the anthozoan phylogeny and across ocean basins. These cryptic lineages co-occur in many reef systems, but their distributions often differ among habitats. Research suggests that cryptic lineages are ecologically specialized and several examples demonstrate differences in thermal tolerance, highlighting the critical implications of this diversity for predicting coral responses to future warming. Here, we draw attention to recent discoveries, discuss how cryptic diversity affects the study of coral adaptation and acclimation to future environments, explore how it shapes symbiotic partnerships, and highlight challenges and opportunities for conservation and restoration efforts.
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Acknowledgements
We would like to thank S. Kitchen for discussions about coral hybrid fertility and Davies lab members for thoughtful feedback. This study was made possible through US National Science Foundation awards to S.W.D. (OCE-2048589), K.S.M.-K. (OCE-2048678) and C.P. (OIA 2032919), and a NOAA award to C.P. (NA22OAR4050072), as well as Boston University and University of Rhode Island start-up funds to S.W.D. and C.P., respectively.
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C.G.B.G. and S.W.D. conceptualized the manuscript. C.G.B.G. and H.E.A conducted the literature analysis with help from all authors. C.G.B.G., M.G.-C., J.E.F., H.E.A., K.S.M.-K., C.P. and S.W.D. all contributed to writing and editing.
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Grupstra, C.G.B., Gómez-Corrales, M., Fifer, J.E. et al. Integrating cryptic diversity into coral evolution, symbiosis and conservation. Nat Ecol Evol 8, 622–636 (2024). https://doi.org/10.1038/s41559-023-02319-y
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DOI: https://doi.org/10.1038/s41559-023-02319-y
