So that light was made by a bioluminescent dinoflagellate, a single celled alga.

Institution for the Use of Micro alga Spirulina against Malnutrition (Council decision 2003 212)

Institution for the Use of Micro alga Spirulina against Malnutrition (Council decision 2003 212)

So why would a single celled alga need to be able to produce light?

There's a certain alga that swims in the wild, and it needs to navigate towards light in order to photosynthesize optimally.

At its 5th meeting, on 5 March, the Council decided to grant observer status with the Council to the Intergovernmental Institution for the Use of Micro alga Spirulina against Malnutrition.

Emphasizes the importance of intensifying and assisting national activities for the production and use of food micro algae, especially in member countries of the Intergovernmental Institution for the Use of Micro alga Spirulina against Malnutrition