MEPS prepress abstract  -  DOI: https://doi.org/10.3354/meps12441

Temperature and Symbiodinium physiology affect the establishment and development of symbiosis in corals

Vivian R. Cumbo, Madeleine J. H. van Oppen, Andrew H. Baird*

*Email: andrew.baird@jcu.edu.au

ABSTRACT: Symbiotic associations are ubiquitous in nature. In fact, all eukaryotic species harbour microbial symbionts that are essential for their health. Often overlooked, symbiosis is an important factor when predicting how organisms might respond to climate change. Some associations are so tight-knit that rapid changes in the environment can lead to extinction of one or both partners. Alternatively, the ability to switch to more stress-tolerant partners can allow for rapid adjustment to environmental change, such as increases in host range size. Here, we outline a mechanism by which symbiotic species that acquire their symbionts anew each generation might adapt to global warming; transgenerational, environmentally mediated changes in host-symbiont partnerships. At temperatures approximating end of century climate change conditions the larvae of two common scleractinian corals established symbiosis with a novel and more thermo-tolerant symbiont. Conversely, the establishment of symbiosis with heat-sensitive symbionts was greatly reduced. Transgenerational change in symbionts is a mechanism by which organisms that engage in flexible mutualistic relationships can rapidly adjust to a changing climate.