Selective breeding slightly increases corals’ tolerance to heat, but reducing global emissions is still vital to help corals survive future warming. A new study has shown that selective breeding can lead to a modest increase in the heat tolerance of corals.
A team of experts from the University of Newcastle’s Coralassist Laboratory has carried out the world’s first study of selective breeding of adult corals to improve thermostability – the ability to withstand extreme marine heatwaves. The study showed that this breeding approach was successful and that the heat tolerance of adult coral juveniles could be improved even in a single generation.
But this recovery was modest compared to expected future marine heatwaves due to climate change. The authors emphasize that a rapid reduction in global greenhouse gas emissions is an absolute necessity to reduce warming and allow corals to adapt.
The research was published in the journal Nature Communication. Organized in partnership with the University of Victoria, Horniman Museum and Gardens, Palau International Coral Reef Centre, University of Derby and University of Exeter. Publication, Dr. It is the result of a five-year project initiated by James Guest with funding from the European Research Council.
Not an ideal solution
“This study shows that selective breeding is a feasible but not ideal solution and further research is needed to maximize breeding outcomes,” says lead study author Liam Lachs, a research fellow at the University of Newcastle. He continues: “In parallel, rapid reductions in global greenhouse gas emissions are an absolute necessity to reduce warming and allow corals to adapt.
Dr. is a lecturer in coral reef ecology at the University of Newcastle’s School of Natural and Environmental Sciences. Guest explains: ‘The results suggest that selective breeding may be a viable tool to increase population resilience. Despite all this, there are still many challenges to overcome. How much coral should be planted to benefit wild populations? Can we guarantee that no compromises will be made (the evidence suggests this is not a major risk)? How can we prevent the dilution of selected features after they are released into nature? How can we maximize election responses?
“Given the modest levels of recovery we found in this study, the effectiveness of such interventions will also depend on urgent climate action.”
A successful breeding attempt
Selective breeding has been practiced by humans for thousands of years to produce animals and plants with desirable traits. It is now seen as a tool for the protection of nature, especially coral reefs. These marine ecosystems are at the forefront of climate change impacts, as reef-building corals are highly sensitive to marine heat waves. This could trigger massive coral bleaching and extinctions that are already leading to significant declines in reef numbers worldwide.
Experts conducted selection tests for two different characteristics: short-term exposure to intense heat (10 days, reaching +3.5°C) or less intense but long-term exposure to more typical natural marine heat waves (1 month, + reaching 2.5 °C).
The team found that selecting parental colonies for high rather than low heat tolerance increased the tolerance of adult offspring. This result holds for both 10-day and 1-month exposure responses. Thermal tolerance could theoretically be increased by approximately 1 °C per week over a generation. But this level of increase is probably not enough to keep up with continued warming.
What’s next?
Selective breeding for short-stress tolerance showed no evidence of increased ability of offspring to withstand long-term heat stress. Since no genetic correlation has been found, these traits are likely to be under independent genetic control. This will have important implications as interventions will benefit from inexpensive and rapid assays that can effectively identify heat-tolerant colonies for breeding. However, if these analyzes do not predict that adult colonies will survive natural marine heat waves, this poses a serious problem for management interventions.
The lead author of the study is Dr. Adriana Humanes emphasizes: “There is significant work to be done before selective breeding can be implemented successfully. “A deeper understanding is needed to determine which traits to prioritize and how these traits are genetically related.”
Take the message home
The authors say the study is an important proof of concept: It is possible to selectively breed corals for adult survival during the rut. They are now calling for more research and development to understand how to implement reproductive interventions and maximize results to keep up with the lower levels of warming that could be achieved through simultaneous climate action.
Source: Port Altele
