DIVERGEN · A small window to the future of our oceans: genomic divergence, plasticity and microbiome shifts in marine invertebrates along natural pH gradients

A small window to the future of our oceans: genomic divergence, plasticity and microbiome shifts in marine invertebrates along natural pH gradients

Ocean acidification is a major consequence of rising atmospheric CO2. As oceans absorb increasing amounts of carbon dioxide, seawater chemistry changes and pH declines, threatening marine biodiversity, ecosystem functioning and services such as fisheries and coastal protection. Calcifying organisms, including sea urchins, are particularly vulnerable because reduced carbonate availability impairs skeletal formation. However, species differ in their capacity to tolerate acidified conditions. Predicting ecosystem responses therefore, requires understanding the biological mechanisms that enable some organisms to persist under long-term exposure to low pH. Most research has relied on short-term laboratory experiments, which may not capture adaptive or compensatory mechanisms occurring in natural environments. Emerging evidence also suggests that resilience may depend not only on genetic adaptation and physiological plasticity, but also on interactions with associated microbial communities. The role of host–microbiome interactions in climate stress tolerance remains poorly understood. This project investigated the mechanisms enabling the sea urchin Arbacia lixula to persist in naturally acidified environments using a CO2 vent system in the Canary Islands as a real-world analogue of future oceans. The study examined metabolic performance, gene expression and early life-stage responses under contrasting pH conditions, while assessing the contribution of larval-associated microbiomes to stress tolerance. By integrating ecological experiments with transcriptomic and microbiome analyses, the project aimed to disentangle the roles of evolutionary adaptation, phenotypic plasticity and symbiotic interactions in shaping resilience to ocean acidification. The results strengthen the scientific basis for anticipating ecosystem shifts under climate change and contribute to European priorities on climate action and ocean health.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз