Temperatures are rising in the oceans and the first victims are coral reefs. This worries biologists because coral reefs are home to the most diverse ecosystems of marine wildlife, including more than 4,000 species of fish.
Now scientists intend to increase the resistance of the corals and use organisms that they have cultivated in laboratories for this purpose.
Corals live in close symbiosis with algae. The algae are well protected in the skin cells of the corals and pay rent in the form of energy they generate through photosynthesis.
Get rid of hot algae
As the temperature rises, the algae overheat and the corals push them out of their cells. The result will be so-called coral bleaching because the corals will turn completely white and die from lack of nutrition.
For this reason, a group of researchers at the University of Melbourne in Australia have bred a genetically modified version of the algae to increase their heat tolerance.
From one genetically modified algae, 100 generations have been grown over the course of four years, which have become accustomed to a sea temperature of 31 degrees, which corresponds to the temperature at the Great Barrier Reef during heat waves.
Withstand 31 degrees
The algae were then tested in a kind of aquarium where they coexisted with corals. The best varieties produced very promising results. Coral larvae took in the algae and kept them in their cells even though the temperature was increased to 31 degrees.
The scientists explain the success by the fact that the genetically modified algae have developed the ability to reduce their photosynthesis, but as a result, there will be less toxic waste, which in turn allows the corals to live with the algae inside.
Before the algae are released into the ocean, however, the scientists want to better study the effects of the gene changes and also find out whether the new algae have the ability to withstand competition with other algae in the natural environment.