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Phenotypic plasticity is defined as a property of individual genotypes to produce different phenotypes when exposed to different environmental conditions. This ability may be expressed at behavioral, biochemical, physiological, and/or developmental levels, exerting direct influence over species' demographic performance. In reef-building corals, a group critically threatened by global change in the Anthropocene, non-genetic mechanisms (i.e., epigenetic and microbiome variation) have been shown to participate in plastic physiological responses to environmental change. Yet, the precise way in which these mechanisms interact, contribute to such responses, and their adaptive potential is still obscure. The present work aims to fill this gap by using a multi-omics approach to elucidate the contribution and interconnection of the mechanisms modulating phenotypic plasticity in staghorn coral (Acropora cervicornis) clones subject to different depth conditions. Results show changes in lipidome, epigenome and transcriptome, but not in symbiotic and microbial communities. In addition, a potential shift toward a more heterotrophic feeding behavior was evidenced in corals at the deeper site. These observations are consistent with a multi-mechanism modulation of rapid acclimation in corals, underscoring the complexity of this process and the importance of a multifactorial approach to inform potential intervention to enhance coral adaptive capacity.
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Avenues of reef-building coral acclimatization in response to rapid environmental change
ABSTRACT The swiftly changing climate presents a challenge to organismal fitness by creating a mismatch between the current environment and phenotypes adapted to historic conditions. Acclimatory mechanisms may be especially crucial for sessile benthic marine taxa, such as reef-building corals, where climate change factors including ocean acidification and increasing temperature elicit strong negative physiological responses such as bleaching, disease and mortality. Here, within the context of multiple stressors threatening marine organisms, I describe the wealth of metaorganism response mechanisms to rapid ocean change and the ontogenetic shifts in organism interactions with the environment that can generate plasticity. I then highlight the need to consider the interactions of rapid and evolutionary responses in an adaptive (epi)genetic continuum. Building on the definitions of these mechanisms and continuum, I also present how the interplay of the microbiome, epigenetics and parental effects creates additional avenues for rapid acclimatization. To consider under what conditions epigenetic inheritance has a more substantial role, I propose investigation into the offset of timing of gametogenesis leading to different environmental integration times between eggs and sperm and the consequences of this for gamete epigenetic compatibility. Collectively, non-genetic, yet heritable phenotypic plasticity will have significant ecological and evolutionary implications for sessile marine organism persistence under rapid climate change. As such, reef-building corals present ideal and time-sensitive models for further development of our understanding of adaptive feedback loops in a multi-player (epi)genetic continuum.
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- Award ID(s):
- 1756623
- PAR ID:
- 10231213
- Date Published:
- Journal Name:
- Journal of Experimental Biology
- Volume:
- 224
- Issue:
- Suppl_1
- ISSN:
- 0022-0949
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1242/jeb.239319
