What is the "tragety of the Commons"? Give an example of a modern commons

The tragedy of the commons describes a situation in economic science when individual users, who have open access to a resource unhampered by shared social structures

Explanation:

answer: 20 percent

the fish culture has become a developing commercial practice in developing countries which is already prominent in developed countries of the world. the major fish protein demand is being supplemented in developing countries is   fishing to meet the needs of the growing population. therefore, in some developing nations, the percentage of animal protein from fish in the diet can be as high as 20 percent.