This happens with "bacalhau" (norwegian codfish). It's appreciated by the europeans for ages, but overfishing made it prohibitively priced. Now you have 5 or 6

This happens with "bacalhau" (norwegian codfish). It's appreciated by the europeans for ages, but overfishing made it prohibitively priced. Now you have 5 or 6 different fish sold under this name at markets, fished on Alaska and China, but they taste all the same so it makes no difference (only on the price). The word "bacalhau" now refers more to the kind of preparation (dried fish) than the species itself. It could be the same with tuna ("tuna" being, any red meat fish with the same consistency and similar taste).